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  <front>
    <journal-meta>
      <journal-id journal-id-type="nlm-ta">Arq Bras Cardiol</journal-id>
      <journal-id journal-id-type="publisher-id">abc</journal-id>
      <journal-title-group>
        <journal-title>Arquivos Brasileiros de Cardiologia</journal-title>
        <abbrev-journal-title abbrev-type="publisher">Arq. Bras. Cardiol.</abbrev-journal-title>
      </journal-title-group>
      <issn pub-type="ppub">0066-782X</issn>
      <issn pub-type="epub">1678-4170</issn>
      <publisher>
        <publisher-name>Sociedade Brasileira de Cardiologia - SBC</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id specific-use="scielo-v3" pub-id-type="publisher-id">WJp4bxRq8WWJw9WBCSnvBVk</article-id>
      <article-id specific-use="scielo-v2" pub-id-type="publisher-id">S0066-782X2021000701039</article-id>
      <article-id pub-id-type="publisher-id">abc.20190089</article-id>
      <article-id pub-id-type="doi">10.36660/abc.20190089</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Artigo Original</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Idade Avan&#231;ada Reduz a Tipicidade da Apresenta&#231;&#227;o Cl&#237;nica em Pacientes Com Dor Tor&#225;cica Aguda Relacionada a Doen&#231;a Coron&#225;ria Obstrutiva?</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Filgueiras</surname>
            <given-names>Pedro Henrique Correia</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Cerqueira</surname>
            <given-names>Ant&#244;nio Maur&#237;cio</given-names>
            <suffix>Junior</suffix>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Bagano</surname>
            <given-names>Gabriela Oliveira</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Correia</surname>
            <given-names>Vitor Calixto de Almeida</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Lopes</surname>
            <given-names>Fernanda Oliveira de Andrade</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Souza</surname>
            <given-names>Thiago Menezes Barbosa de</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Fonseca</surname>
            <given-names>Leticia Lara</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Kertzman</surname>
            <given-names>Lara Queiroz</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Lacerda</surname>
            <given-names>Yasmin Falcon</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-6800-8100</contrib-id>
          <name>
            <surname>Rabelo</surname>
            <given-names>Marcia Noya</given-names>
          </name>
          <xref ref-type="aff" rid="aff2">
            <sup>2</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-6910-1366</contrib-id>
          <name>
            <surname>Correia</surname>
            <given-names>Luis Claudio Lemos</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
      </contrib-group>
      <aff id="aff1">
        <label> 1 </label>
        <institution content-type="orgname">Escola Bahiana de Medicina e Sa&#250;de P&#250;blica</institution>
        <addr-line>
          <named-content content-type="city">Salvador</named-content>
          <named-content content-type="state">BA</named-content>
        </addr-line>
        <country country="BR">Brasil</country>
        <institution content-type="original"> Escola Bahiana de Medicina e Sa&#250;de P&#250;blica (EBMSP), Salvador , BA - Brasil </institution>
      </aff>
      <aff id="aff2">
        <label> 2 </label>
        <institution content-type="orgname">Hospital S&#227;o Rafael</institution>
        <addr-line>
          <named-content content-type="city">Salvador</named-content>
          <named-content content-type="state">BA</named-content>
        </addr-line>
        <country country="BR">Brasil</country>
        <institution content-type="original"> Hospital S&#227;o Rafael , Salvador , BA - Brasil </institution>
      </aff>
      <author-notes>
        <corresp id="c01">Correspond&#234;ncia: Luis C. L. Correia &#8226; Av. Princesa Leopoldina 19/402. CEP 40150-080, Salvador, BA &#8211; Brasil Email: <email>luisclcorreia@gmail.com</email> </corresp>
        <fn fn-type="con">
          <p>Contribui&#231;&#227;o dos autores</p>
          <p>Concep&#231;&#227;o e desenho da pesquisa: Filgueiras PHC, Cerqueira Junior AM, Correia LCL, Lopes FOA; Obten&#231;&#227;o de dados: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Souza TMB, Fonseca LL, Kertzman LQ, Lacerda YF, Rabelo MN, Lopes FOA; An&#225;lise e interpreta&#231;&#227;o dos dados: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Souza TMB, Lopes FOA; An&#225;lise estat&#237;stica: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Fonseca LL, Kertzman LQ, Lacerda YF, Rabelo MN, Correia LCL, Lopes FOA; Revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Souza TMB, Fonseca LL, Kertzman LQ, Lacerda YF, Rabelo MN, Correia LCL, Lopes FOA.</p>
        </fn>
        <fn fn-type="conflict">
          <p>Potencial conflito de interesse</p>
          <p>N&#227;o h&#225; conflito com o presente artigo</p>
        </fn>
      </author-notes>
      <pub-date date-type="pub" publication-format="electronic">
        <day>14</day>
        <month>06</month>
        <year>2021</year>
      </pub-date>
      <pub-date date-type="collection" publication-format="electronic">
        <month>06</month>
        <year>2021</year>
      </pub-date>
      <volume>116</volume>
      <issue>6</issue>
      <fpage>1039</fpage>
      <lpage>1045</lpage>
      <history>
        <date date-type="received">
          <day>08</day>
          <month>07</month>
          <year>2019</year>
        </date>
        <date date-type="rev-recd">
          <day>23</day>
          <month>03</month>
          <year>2020</year>
        </date>
        <date date-type="accepted">
          <day>14</day>
          <month>05</month>
          <year>2020</year>
        </date>
      </history>
      <permissions>
        <license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/" xml:lang="en">
          <license-p>This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.</license-p>
        </license>
      </permissions>
      <abstract>
        <title>Resumo</title>
        <sec>
          <title>Fundamento</title>
          <p>De acordo com o pensamento diagn&#243;stico tradicional, indiv&#237;duos muito idosos est&#227;o mais predispostos a desenvolver sintomas at&#237;picos em s&#237;ndromes coronarianas agudas.</p>
        </sec>
        <sec>
          <title>Objetivo</title>
          <p>Testar a hip&#243;tese de que indiv&#237;duos muito idosos est&#227;o mais predispostos a manifesta&#231;&#245;es de dor tor&#225;cica at&#237;pica devido &#224; doen&#231;a arterial coronariana obstrutiva (DAC).</p>
        </sec>
        <sec>
          <title>M&#233;todos</title>
          <p>O Registro de dor tor&#225;cica inclui pacientes internados com dor tor&#225;cica aguda. Primeiramente, foi constru&#237;do o &#237;ndice de tipicidade dessa manifesta&#231;&#227;o cl&#237;nica: a soma de 12 caracter&#237;sticas de sintomas (8 sintomas t&#237;picos e 4 sintomas at&#237;picos). No subgrupo de pacientes com etiologia coronariana, o &#237;ndice de tipicidade foi comparado entre octogen&#225;rios e n&#227;o octogen&#225;rios. A signific&#226;ncia estat&#237;stica foi definida por p&lt;0,05.</p>
        </sec>
        <sec>
          <title>Resultados</title>
          <p>958 pacientes foram inclu&#237;dos no registro, sendo que 486 (51%) tinham etiologia supostamente coronariana. Nesse grupo, 59 (12%) octogen&#225;rios (idade 84&#177;3,5; 50% homens) foram comparados a 427 pacientes com idade &lt;80 (60&#177;12 anos; 71% homens). O &#237;ndice de tipicidade em octogen&#225;rios foi 3,42&#177;1,92, que &#233; semelhante ao de n&#227;o octogen&#225;rios (3,44&#177;1,74; p=0,092 na an&#225;lise univariada e p=0,80 ap&#243;s ajuste para sexo pela an&#225;lise de vari&#226;ncia &#8212; ANOVA). Tamb&#233;m n&#227;o houve diferen&#231;a estatisticamente significativa quando a amostra foi dividida em idade mediana (62 anos; 3,41&#177;1,77 vs. 3,49 &#177; 1,77; p=0,61). N&#227;o houve associa&#231;&#227;o linear estatisticamente significativa entre idade e &#237;ndice de tipicidade (r=- 0,05; p=0,24). A an&#225;lise de regress&#227;o log&#237;stica para predi&#231;&#227;o de DAC na amostra geral de 958 pacientes n&#227;o mostrou intera&#231;&#227;o do &#237;ndice de tipicidade com a idade num&#233;rica (p=0,94), octogen&#225;rios (p=0,22) ou idade acima da mediana (p=0,74).</p>
        </sec>
        <sec>
          <title>Conclus&#227;o</title>
          <p>Em pacientes com dor tor&#225;cica aguda de etiologia coronariana, a idade avan&#231;ada n&#227;o influencia o quadro cl&#237;nico t&#237;pico.</p>
        </sec>
      </abstract>
      <kwd-group xml:lang="pt">
        <kwd>Idoso</kwd>
        <kwd>Dor no Peito</kwd>
        <kwd>S&#237;ndrome Coronariana Aguda</kwd>
        <kwd>Progn&#243;stico</kwd>
      </kwd-group>
      <counts>
        <fig-count count="6"/>
        <table-count count="4"/>
        <equation-count count="0"/>
        <ref-count count="5"/>
        <page-count count="7"/>
      </counts>
    </article-meta>
  </front>
  <body>
    <sec sec-type="intro">
      <title>Introdu&#231;&#227;o</title>
      <p>O pensamento cl&#237;nico tradicional indica que os idosos est&#227;o predispostos a sintomas at&#237;picos nas s&#237;ndromes coronarianas agudas (SCA), condi&#231;&#227;o que pode implicar em dif&#237;cil diagn&#243;stico e tratamento tardio. <sup><xref ref-type="bibr" rid="B1">1</xref></sup> Os mecanismos plaus&#237;veis para atipicidade seriam limita&#231;&#245;es cognitivas, comunica&#231;&#227;o comprometida ou redu&#231;&#227;o da percep&#231;&#227;o da dor. <sup><xref ref-type="bibr" rid="B2">2</xref></sup></p>
      <p>No entanto, embora esse pensamento cl&#237;nico tradicional tenha como poss&#237;vel base fisiol&#243;gica a altera&#231;&#227;o nociceptiva causada pela depress&#227;o e diabetes, que s&#227;o mais prevalentes em indiv&#237;duos com mais idade, a grande maioria dos estudos encontrados na literatura &#233; retrospectiva e com uma defini&#231;&#227;o bastante vari&#225;vel e subjetiva de &#8220;tipicidade da dor&#8221;. Portanto, ainda n&#227;o est&#225; claro se, de fato, a idade avan&#231;ada implica um quadro cl&#237;nico diferente no contexto das s&#237;ndromes coronarianas. <sup><xref ref-type="bibr" rid="B3">3</xref> , <xref ref-type="bibr" rid="B4">4</xref></sup></p>
      <p>Assim, o presente estudo se prop&#245;e a testar a hip&#243;tese de que indiv&#237;duos muito idosos est&#227;o mais predispostos a manifesta&#231;&#245;es at&#237;picas de dor tor&#225;cica de etiologia coronariana. Como uma an&#225;lise prim&#225;ria, a tipicidade geral da manifesta&#231;&#227;o cl&#237;nica foi comparada entre octogen&#225;rios e n&#227;o octogen&#225;rios na subamostra de pacientes com etiologia coronariana. Seguiu-se a an&#225;lise da intera&#231;&#227;o entre idade e tipicidade da dor na predi&#231;&#227;o da etiologia coronariana na amostra de todas as etiologias de dor tor&#225;cica.</p>
    </sec>
    <sec sec-type="methods">
      <title>M&#233;todos</title>
      <sec>
        <title>Sele&#231;&#227;o da amostra</title>
        <p>O Registro de Dor Tor&#225;cica &#233; uma amostra de pacientes internados consecutivamente na Unidade Coronariana de um hospital terci&#225;rio de setembro de 2011 a dezembro de 2017, principalmente por desconforto tor&#225;cico, independentemente de altera&#231;&#245;es eletrocardiogr&#225;ficas, marcadores de necrose ou qualquer outro exame complementar que mostre a causa do sintoma.</p>
        <p>A amostra selecionada tem como objetivo representar a popula&#231;&#227;o-alvo de pacientes internados na unidade coronariana devido a dor tor&#225;cica. Assim, todos os pacientes internados durante o per&#237;odo do estudo foram inclu&#237;dos no estudo, n&#227;o havendo sele&#231;&#227;o de subamostra nesta popula&#231;&#227;o. A interna&#231;&#227;o na unidade coronariana n&#227;o foi influenciada pelo protocolo do estudo. A probabilidade diagn&#243;stica foi estabelecida a crit&#233;rio dos m&#233;dicos assistentes.</p>
        <p>O estudo est&#225; de acordo com as normas &#233;ticas da resolu&#231;&#227;o 510/2016 do Minist&#233;rio da Sa&#250;de, foi aprovado pelo Comit&#234; de &#201;tica em Pesquisa Hospitalar e todos os participantes assinaram o termo de consentimento livre e esclarecido.</p>
      </sec>
      <sec>
        <title>Caracteriza&#231;&#227;o do desconforto tor&#225;cico</title>
        <p>Na interna&#231;&#227;o, as informa&#231;&#245;es sobre a apresenta&#231;&#227;o cl&#237;nica do desconforto tor&#225;cico foram coletadas por meio de entrevista parametrizada. A entrevista foi realizada de forma sistematizada por pesquisadores treinados para evitar induzir as respostas dos pacientes e focar na reprodutibilidade do m&#233;todo. A entrevista foi parametrizada para exigir respostas objetivas sim/n&#227;o. Quando o paciente manifestou d&#250;vida, o sintoma foi considerado ausente.</p>
        <p>Foram avaliadas 12 caracter&#237;sticas de sintomas, incluindo 8 caracter&#237;sticas consideradas t&#237;picas de angina (dor precordial, aspecto compressivo, irradia&#231;&#227;o para membro superior esquerdo, irradia&#231;&#227;o para o pesco&#231;o, intensidade classificada pelo paciente como grave, desconforto nos dias anteriores, presen&#231;a de sintomas vagais, administra&#231;&#227;o de medica&#231;&#227;o sublingual seguida de melhora do sintoma) e 4 caracter&#237;sticas consideradas at&#237;picas (mudan&#231;a da dor conforme a posi&#231;&#227;o, mudan&#231;a com palpa&#231;&#227;o do local, mudan&#231;a com movimento do bra&#231;o e mudan&#231;a com respira&#231;&#227;o).</p>
      </sec>
      <sec>
        <title>&#205;ndice de tipicidade de sintomas</title>
        <p>Para quantificar a tipicidade geral da manifesta&#231;&#227;o cl&#237;nica, atribuiu-se 1 ponto a cada caracter&#237;stica t&#237;pica e subtraiu-se 1 ponto para cada caracter&#237;stica at&#237;pica (varia&#231;&#227;o de -4 a +8, proporcional &#224; tipicidade).</p>
      </sec>
      <sec>
        <title>Defini&#231;&#227;o da etiologia dos sintomas</title>
        <p>Para a avalia&#231;&#227;o diagn&#243;stica, os pacientes foram submetidos a angiografia coron&#225;ria invasiva ou teste provocativo n&#227;o invasivo (resson&#226;ncia magn&#233;tica de perfus&#227;o nuclear e tomografia computadorizada por emiss&#227;o de f&#243;ton &#250;nico ou ecocardiografia sob estresse com dobutamina), a crit&#233;rio do cardiologista respons&#225;vel. Para testes n&#227;o invasivos positivos, os pacientes fizeram uma angiografia para confirma&#231;&#227;o. Com base nesse algoritmo de diagn&#243;stico, definiu-se doen&#231;a arterial coronariana obstrutiva (DACO) como estenose &#8805;70% na angiografia. A angiografia coron&#225;ria sem les&#227;o obstrutiva ou teste n&#227;o invasivo normal (tamanho do defeito isqu&#234;mico &lt;5% do mioc&#225;rdio ventricular esquerdo) indicou aus&#234;ncia de DACO.</p>
      </sec>
      <sec>
        <title>An&#225;lise dos dados</title>
        <p>A normalidade das vari&#225;veis num&#233;ricas foi testada por histograma, comparando m&#233;dia e mediana, e considerando principalmente o n&#237;vel de curtose e assimetria &lt;3. Indiv&#237;duos muito idosos foram definidos com idade &#8805;80 anos (octogen&#225;rios). Realizou-se a an&#225;lise preliminar na amostra de pacientes com doen&#231;a coronariana obstrutiva, comparando o &#237;ndice de tipicidade entre octogen&#225;rios e n&#227;o octogen&#225;rios. Al&#233;m disso, comparou-se cada caracter&#237;stica de sintomas entre os dois grupos. As vari&#225;veis num&#233;ricas foram expressas como m&#233;dia e desvio padr&#227;o, comparadas entre os dois grupos pelo teste t de Student n&#227;o pareado. As vari&#225;veis categ&#243;ricas foram expressas em propor&#231;&#245;es e comparadas com o teste qui-quadrado de Pearson. Procedeu-se &#224; an&#225;lise de vari&#226;ncia para comparar o &#237;ndice de tipicidade entre os grupos ap&#243;s ajuste para sexo. A associa&#231;&#227;o linear entre &#237;ndice de tipicidade e idade foi testada pelo coeficiente de correla&#231;&#227;o de Pearson, com base na distribui&#231;&#227;o normal de ambas as vari&#225;veis. A compara&#231;&#227;o m&#250;ltipla foi ajustada pelo m&#233;todo de Bonferroni.</p>
        <p>Em seguida, utilizou-se a amostra total do registro (todos os pacientes admitidos com dor tor&#225;cica aguda, com e sem doen&#231;a arterial coronariana), e avaliamos a capacidade preditiva do &#237;ndice de tipicidade para doen&#231;a arterial coronariana obstrutiva com base na &#225;rea sob a curva <italic>Receiver Operator Characteristic</italic> (ROC). Depois, avaliamos o efeito modificador da idade sobre a precis&#227;o do diagn&#243;stico (DACO) da tipicidade geral da dor, em termos de intera&#231;&#227;o vs. tipicidade da idade na regress&#227;o log&#237;stica, com a idade sendo inserida de tr&#234;s maneiras diferentes: como uma vari&#225;vel num&#233;rica, categorizada em dois grupos (octogen&#225;rios ou n&#227;o octogen&#225;rios) e categorizada em dois grupos a partir da mediana da amostra. Para a an&#225;lise estat&#237;stica, foi utilizado o software SPSS vers&#227;o 23. A signific&#226;ncia estat&#237;stica foi definida como um valor de p bicaudal menor que 0,05.</p>
      </sec>
      <sec>
        <title>C&#225;lculo amostral</title>
        <p>Quanto ao c&#225;lculo amostral, trata-se de um estudo realizado em amostra previamente existente no Registro de Dor Tor&#225;cica, uma coleta prospectiva de pacientes internados por dor tor&#225;cica. Esse registro &#233; utilizado para v&#225;rias an&#225;lises e, em nossa metodologia, antes de decidirmos testar qualquer hip&#243;tese, avaliamos o poder estat&#237;stico, que depende do comportamento da vari&#225;vel em quest&#227;o. Assim, como os dados j&#225; haviam sido coletados, poder&#237;amos utilizar o desvio padr&#227;o da amostra que seria utilizado para avaliar se o tamanho da amostra tinha poder suficiente, crit&#233;rio essencial para permitir a an&#225;lise dos dados em nosso protocolo.</p>
        <p>Assim, o tamanho da amostra foi definido primeiro, com base na distribui&#231;&#227;o do &#237;ndice de tipicidade na amostra de doen&#231;a coronariana. Considerando o desvio padr&#227;o de 1,7, seria necess&#225;rio que 36 octogen&#225;rios e 109 n&#227;o octogen&#225;rios oferecessem 80% de poder na detec&#231;&#227;o de uma diferen&#231;a de 30% no &#237;ndice t&#237;pico pelo teste t de Student.</p>
      </sec>
    </sec>
    <sec sec-type="results">
      <title>Resultados</title>
      <sec>
        <title>Caracteriza&#231;&#227;o da amostra</title>
        <p>Entre setembro de 2011 e dezembro de 2017, 958 indiv&#237;duos foram inclu&#237;dos no registro, e 486 (51%) tinham etiologia supostamente coronariana. Nesse grupo, 59 octogen&#225;rios foram comparados a 427 n&#227;o octogen&#225;rios. A m&#233;dia de idade dos octogen&#225;rios foi de 85&#177;3,4 anos, sendo 56% homens, em compara&#231;&#227;o com 60&#177;12 anos, sendo 71% homens, no grupo de n&#227;o octogen&#225;rios (p&lt;0,001). Pacientes octogen&#225;rios tiveram uma preval&#234;ncia maior de disfun&#231;&#227;o ventricular esquerda clinicamente manifesta (24% versus 8,7%, p&lt;0,001), doen&#231;a triarterial ou tronco de coron&#225;ria esquerda (41% versus 26%, p=0,01) e menor preval&#234;ncia de infarto agudo do mioc&#225;rdio com eleva&#231;&#227;o do segmento ST (25% versus 30%, p&lt;0,001). A mortalidade foi maior no grupo com idade mais avan&#231;ada (14% versus 2,1%, p&lt;0,001). As vari&#225;veis comparadas entre os dois grupos encontram-se discriminadas na <xref ref-type="table" rid="t1">tabela 1</xref> .</p>
        <p>
          <table-wrap id="t1">
            <label>Tabela 1</label>
            <caption>
              <title>&#8211; Caracter&#237;sticas cl&#237;nicas e comorbidades</title>
            </caption>
            <table frame="hsides" rules="groups">
              <colgroup>
                <col/>
                <col/>
                <col/>
                <col/>
              </colgroup>
              <thead>
                <tr>
                  <th align="left" style="font-weight:normal"> </th>
                  <th>Idade &lt;80 anos (n=427)</th>
                  <th>Idade &#8805;80 anos (n=59)</th>
                  <th>Valor de p</th>
                </tr>
              </thead>
              <tbody>
                <tr>
                  <td>Idade (anos)</td>
                  <td align="center">60&#177;12</td>
                  <td align="center">85&#177;3,4</td>
                  <td align="center">&lt;0,001</td>
                </tr>
                <tr>
                  <td>Homens</td>
                  <td align="center">302 (71%)</td>
                  <td align="center">33 (56%)</td>
                  <td align="center">0,02</td>
                </tr>
                <tr>
                  <td>Isquemia ao ECG</td>
                  <td align="center">279 (67%)</td>
                  <td align="center">37 (65%)</td>
                  <td align="center">0,80</td>
                </tr>
                <tr>
                  <td>Troponina positiva</td>
                  <td align="center">274 (65%)</td>
                  <td align="center">49 (83%)</td>
                  <td align="center">0,005</td>
                </tr>
                <tr>
                  <td>Infarto com supradesnivelamento do segmento ST</td>
                  <td align="center">127 (30%)</td>
                  <td align="center">15 (25%)</td>
                  <td align="center">&lt;0,001</td>
                </tr>
                <tr>
                  <td>Diabetes mellitus</td>
                  <td align="center">161 (38%)</td>
                  <td align="center">27 (46%)</td>
                  <td align="center">0,23</td>
                </tr>
                <tr>
                  <td>Creatinina (mg/dL)</td>
                  <td align="center">1,0&#177;0,69</td>
                  <td align="center">1,1&#177;0,43</td>
                  <td align="center">0,12</td>
                </tr>
                <tr>
                  <td>Press&#227;o arterial sist&#243;lica (mmHg)</td>
                  <td align="center">154&#177;31</td>
                  <td align="center">153&#177;36</td>
                  <td align="center">0,08</td>
                </tr>
                <tr>
                  <td>Frequ&#234;ncia card&#237;aca (bpm)</td>
                  <td align="center">78&#177;18</td>
                  <td align="center">76&#177;19</td>
                  <td align="center">0,17</td>
                </tr>
                <tr>
                  <td>Doen&#231;a coronariana pr&#233;via</td>
                  <td align="center">139 (33%)</td>
                  <td align="center">24 (41%)</td>
                  <td align="center">0,22</td>
                </tr>
                <tr>
                  <td>Revasculariza&#231;&#227;o mioc&#225;rdica pr&#233;via</td>
                  <td align="center">37 (8,7%)</td>
                  <td align="center">7 (12%)</td>
                  <td align="center">0,40</td>
                </tr>
                <tr>
                  <td>Padr&#227;o anat&#244;mico grave*</td>
                  <td align="center">80 (26%)</td>
                  <td align="center">16 (41%)</td>
                  <td align="center">0,01</td>
                </tr>
              </tbody>
            </table>
            <table-wrap-foot>
              <fn id="TFN1">
                <p>
                  <italic>*Cateterismo com obstru&#231;&#227;o &#8805;70%. ECG: eletrocardiograma.</italic>
                </p>
              </fn>
            </table-wrap-foot>
          </table-wrap>
        </p>
      </sec>
      <sec>
        <title>Idade e tipicidade dos sintomas</title>
        <p>O &#237;ndice de tipicidade dos pacientes muito idosos foi de 3,42&#177;1,92, semelhante ao observado em indiv&#237;duos mais jovens (3,44&#177;1,74; p=0,92). A compara&#231;&#227;o do &#237;ndice de tipicidade permaneceu n&#227;o significativa (p=0,80) ap&#243;s ajuste para diferen&#231;a de g&#234;nero entre os grupos ( <xref ref-type="fig" rid="f01">Figura 1</xref> ).</p>
        <p>
          <fig id="f01">
            <label>Figura 1</label>
            <caption>
              <title>&#8211; Boxplot do &#237;ndice de tipicidade para os grupos octogen&#225;rios e n&#227;o octogen&#225;rios (p=0,92).</title>
            </caption>
            <graphic xlink:href="1678-4170-abc-116-06-1039-90089-gf01.tif"/></fig>
        </p>
        <p>N&#227;o houve diferen&#231;a no &#237;ndice de tipicidade quando a amostra foi dividida em idade mediana (62 anos), sendo 3,41&#177;1,77 versus 3,49&#177;1,77 (p=0,61). Da mesma forma, n&#227;o houve correla&#231;&#227;o entre &#237;ndice t&#237;pico e idade (r=- 0,05, p=0,24) ( <xref ref-type="fig" rid="f02">Figura 2</xref> ).</p>
        <p>
          <fig id="f02">
            <label>Figura 2</label>
            <caption>
              <title>&#8211; Gr&#225;fico de dispers&#227;o do &#237;ndice t&#237;pico e idade.</title>
            </caption>
            <graphic xlink:href="1678-4170-abc-116-06-1039-90089-gf02.tif"/></fig>
        </p>
        <p>A compara&#231;&#227;o entre as 12 caracter&#237;sticas da dor entre octogen&#225;rios e n&#227;o octogen&#225;rios n&#227;o mostrou diferen&#231;a significativa ap&#243;s o ajuste de Bonferroni ( <xref ref-type="table" rid="t2">Tabela 2</xref> ).</p>
        <p>
          <table-wrap id="t2">
            <label>Tabela 2</label>
            <caption>
              <title>&#8211; Caracter&#237;sticas da dor tor&#225;cica</title>
            </caption>
            <table frame="hsides" rules="groups">
              <colgroup>
                <col/>
                <col/>
                <col/>
                <col/>
                <col/>
              </colgroup>
              <thead>
                <tr>
                  <th align="left" style="font-weight:normal"> </th>
                  <th>Idade &#8805;80 anos</th>
                  <th>Idade &lt;80 anos</th>
                  <th>Valor de p</th>
                  <th>Valor de p ajustado (Bonferroni)</th>
                </tr>
              </thead>
              <tbody>
                <tr>
                  <td>Dor precordial</td>
                  <td align="center">348 (82%)</td>
                  <td align="center">48 (81%)</td>
                  <td align="center">0,98</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Dor compressiva</td>
                  <td align="center">241 (56%)</td>
                  <td align="center">28 (48%)</td>
                  <td align="center">0,19</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Irradia&#231;&#227;o para o membro superior esquerdo</td>
                  <td align="center">167 (39%)</td>
                  <td align="center">19 (32%)</td>
                  <td align="center">0,02</td>
                  <td align="center">0,24</td>
                </tr>
                <tr>
                  <td>Irradia&#231;&#227;o para o pesco&#231;o</td>
                  <td align="center">110 (26%)</td>
                  <td align="center">8 (14%)</td>
                  <td align="center">0,04</td>
                  <td align="center">0,48</td>
                </tr>
                <tr>
                  <td>Intensidade severa</td>
                  <td align="center">253 (60%)</td>
                  <td align="center">39 (66%)</td>
                  <td align="center">0,33</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Desconforto nos dias anteriores</td>
                  <td align="center">67 (48%)</td>
                  <td align="center">14 (67%)</td>
                  <td align="center">0,10</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Sintomas vagais</td>
                  <td align="center">215 (50%)</td>
                  <td align="center">32 (54%)</td>
                  <td align="center">0,58</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Melhora com nitrato</td>
                  <td align="center">182 (43%)</td>
                  <td align="center">18 (31%)</td>
                  <td align="center">0,08</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Muda com a posi&#231;&#227;o</td>
                  <td align="center">70 (16%)</td>
                  <td align="center">7 (12%)</td>
                  <td align="center">0,37</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Muda com palpa&#231;&#227;o</td>
                  <td align="center">26 (6,1%)</td>
                  <td align="center">2 (3,4%)</td>
                  <td align="center">0,40</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Muda com o movimento do bra&#231;o</td>
                  <td align="center">29 (6,8%)</td>
                  <td align="center">3 (5,1%)</td>
                  <td align="center">0,62</td>
                  <td align="center">--</td>
                </tr>
                <tr>
                  <td>Dor pleur&#237;tica</td>
                  <td align="center">51 (12%)</td>
                  <td align="center">5 (8,5%)</td>
                  <td align="center">0,43</td>
                  <td align="center">--</td>
                </tr>
              </tbody>
            </table>
          </table-wrap>
        </p>
      </sec>
      <sec>
        <title>Efeito modificador da idade na capacidade preditiva da tipicidade da dor</title>
        <p>Analisando os 958 pacientes do registro, o &#237;ndice de tipicidade apresentou uma &#225;rea sob a curva ROC de 0,62 (IC 95% = 0,58&#8211;0,65) para predi&#231;&#227;o de doen&#231;a arterial coronariana obstrutiva. A an&#225;lise de regress&#227;o log&#237;stica n&#227;o demonstrou intera&#231;&#227;o do &#237;ndice de tipicidade com idade num&#233;rica (p=0,94), octogen&#225;rios (p= 0,22) ou idade acima da mediana de 62 anos (p=0,74) ( <xref ref-type="fig" rid="f03">Figura 3</xref> ).</p>
        <p>
          <fig id="f03">
            <label>Figura 3</label>
            <caption>
              <title>&#8211; Estat&#237;stica C do &#237;ndice de tipicidade para predi&#231;&#227;o de doen&#231;a arterial coronariana obstrutiva, considerando todos os pacientes no registro (958), curva ROC: 0,62 (95% CI = 0,58&#8211;0,65).</title>
            </caption>
            <graphic xlink:href="1678-4170-abc-116-06-1039-90089-gf03.tif"/></fig>
        </p>
      </sec>
    </sec>
    <sec sec-type="discussion">
      <title>Discuss&#227;o</title>
      <p>O presente estudo demonstra que a idade avan&#231;ada n&#227;o influencia a tipicidade da apresenta&#231;&#227;o cl&#237;nica no contexto das s&#237;ndromes coronarianas agudas. Al&#233;m disso, o valor diagn&#243;stico da manifesta&#231;&#227;o cl&#237;nica n&#227;o &#233; influenciado pela idade. Conforme mostrado, mesmo analisando a &#8220;idade avan&#231;ada&#8221; sob v&#225;rias perspectivas (dividindo a amostra entre octogen&#225;rios e n&#227;o octogen&#225;rios, idade mediana, 62 anos, e ainda colocando a idade como uma vari&#225;vel cont&#237;nua), nenhuma das an&#225;lises sugeriu influ&#234;ncia.</p>
      <p>A utiliza&#231;&#227;o de um &#8220;&#237;ndice de tipicidade&#8221; permitiu analisar a tipologia geral da dor, informa&#231;&#227;o complementada pela an&#225;lise individual de cada caracter&#237;stica. O chamado &#8220;&#237;ndice&#8221; &#233; apenas a contagem dos sintomas sugeridos menos os sintomas n&#227;o sugeridos, uma forma de tratar a tipicidade como vari&#225;vel num&#233;rica, evitando a subjetividade da categoriza&#231;&#227;o em um quadro cl&#237;nico t&#237;pico ou at&#237;pico.</p>
      <p>Outro ponto importante deste estudo &#233; que, para a defini&#231;&#227;o de DACO, utilizamos a cinecoronariografia, exame padr&#227;o-ouro, o que implica baixo risco de vi&#233;s de calibra&#231;&#227;o.</p>
      <p>Estudos anteriores que buscaram estudar a dor em indiv&#237;duos com idade mais avan&#231;ada com s&#237;ndrome coronariana aguda mostraram resultados controversos. <sup><xref ref-type="bibr" rid="B2">2</xref> , <xref ref-type="bibr" rid="B3">3</xref> , <xref ref-type="bibr" rid="B5">5</xref></sup> Verifica-se que na maioria desses estudos a coleta das caracter&#237;sticas da dor foi feita retrospectivamente e a partir de bancos de dados desenvolvidos com outros objetivos prim&#225;rios.</p>
      <p>Em 2001, Mehta et al., <sup><xref ref-type="bibr" rid="B1">1</xref></sup> por meio de um registro de benefici&#225;rios do Medicare nos EUA, selecionaram pacientes com diagn&#243;stico de infarto agudo do mioc&#225;rdio e estratificaram a amostra com base na idade. <sup><xref ref-type="bibr" rid="B1">1</xref></sup> Em seu estudo, os autores concluem que a apresenta&#231;&#227;o inicial da dor tor&#225;cica diminui com o aumento da idade. No entanto, n&#227;o mostram se h&#225; diferen&#231;a estat&#237;stica entre os valores, o que torna essa conclus&#227;o enganosa.</p>
      <p>Em uma an&#225;lise post-hoc do registro <italic>Internet Tracking Registry for Acute Coronary Syndromes</italic> (i*trACS), Han et al., <sup><xref ref-type="bibr" rid="B3">3</xref></sup> analisaram a apresenta&#231;&#227;o cl&#237;nica em pacientes com SCA de dois grupos: idade &#8805;75 anos e &lt;75 anos. Classificaram a &#8220;apresenta&#231;&#227;o t&#237;pica&#8221; como dor tor&#225;cica em esmagamento, compress&#227;o ou press&#227;o e conclu&#237;ram que apenas no grupo de pacientes mais jovens (idade &lt;75 anos) a apresenta&#231;&#227;o t&#237;pica estava associada ao diagn&#243;stico de SCA. Al&#233;m da defini&#231;&#227;o simplista de &#8220;apresenta&#231;&#227;o t&#237;pica&#8221;, os autores n&#227;o compararam as duas faixas et&#225;rias com diagn&#243;stico de SCA. Em outra an&#225;lise post-hoc, do <italic>Gulf Registry of Acute Coronary Events</italic> ( <italic>Gulf RACE</italic> ), El-Menyar et al. <sup><xref ref-type="bibr" rid="B5">5</xref></sup> classificaram em 3 categorias: t&#237;pica, at&#237;pica e dispneia, n&#227;o sendo encontrada diferen&#231;a de idade nos grupos de apresenta&#231;&#227;o &#8220;t&#237;pica&#8221; (55&#177;12) e &#8220;at&#237;pica&#8221; (57&#177;13). No entanto, os autores atribuem caracter&#237;sticas bastante amplas como sendo &#8220;t&#237;picas&#8221;: &#8220;irradia&#231;&#227;o para o bra&#231;o, ombro, costas, pesco&#231;o, mand&#237;bula, epig&#225;strio ou outros locais,&#8221; o que torna essa classifica&#231;&#227;o subjetiva. Devemos reconhecer que, apesar de satisfazer o c&#225;lculo amostral, nossa popula&#231;&#227;o de pacientes muito idosos era pequena. Al&#233;m disso, nosso estudo foi realizado em apenas um centro e em uma popula&#231;&#227;o selecionada, sendo necess&#225;rio o desenvolvimento de novos estudos neste contexto. Reconhecemos tamb&#233;m que este estudo foi realizado em ambiente de hospital terci&#225;rio, portanto, devemos ter cuidado ao extrapolar seus resultados para o ambiente de aten&#231;&#227;o prim&#225;ria. Nossa popula&#231;&#227;o de maior interesse &#233; a de pacientes internados em unidade coronariana, popula&#231;&#227;o em que o desafio da discrimina&#231;&#227;o diagn&#243;stica &#233; maior, pois h&#225; maior homogeneidade de sintomas (zona de probabilidade cinza). Por ser nossa popula&#231;&#227;o-alvo, n&#227;o houve vi&#233;s de sele&#231;&#227;o. Finalmente, existe uma infinidade de possibilidades e combina&#231;&#245;es de sintomas a serem inclu&#237;dos em uma an&#225;lise como esta. Mas aqui, n&#227;o estamos tentando criar um escore preditor para a etiologia da dor; estamos apenas comparando os muito idosos com os n&#227;o muito idosos quanto &#224; &#8220;carga de tipicidade&#8221;. Independentemente de contemplarmos todos os sintomas poss&#237;veis, o teste de hip&#243;tese para a &#8220;carga de tipicidade&#8221; n&#227;o fica comprometido. Estamos apenas avaliando se existe um gradiente de sintomas entre esses dois grupos.</p>
    </sec>
    <sec sec-type="conclusions">
      <title>Conclus&#227;o</title>
      <p>Em pacientes com dor tor&#225;cica de etiologia coronariana, a idade avan&#231;ada n&#227;o parece influenciar a apresenta&#231;&#227;o cl&#237;nica t&#237;pica, sugerindo que os sintomas devam ser interpretados independentemente da idade.</p>
    </sec>
  </body>
  <back>
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      </ref>
    </ref-list>
    <fn-group>
      <fn fn-type="other">
        <p>Vincula&#231;&#227;o acad&#234;mica</p>
        <p>Este artigo &#233; parte de tese de doutorado de Ant&#244;nio Maur&#237;cio Cerqueira Junior pela Escola Bahiana de Medicina e Sa&#250;de P&#250;blica.</p>
      </fn>
    </fn-group>
    <fn-group>
      <fn fn-type="supported-by">
        <p><bold>Fontes de financiamento</bold>:  O presente estudo n&#227;o teve fontes de financiamento externas.</p>
      </fn>
    </fn-group>
  </back>
  <sub-article article-type="translation" id="TRen" xml:lang="en">
    <front-stub>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Original Article</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Does Advanced Age Reduce the Typicality of Clinical Presentation in Patients with Acute Chest Pain Related to Coronary Artery Disease?</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Filgueiras</surname>
            <given-names>Pedro Henrique Correia</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Cerqueira</surname>
            <given-names>Ant&#244;nio Maur&#237;cio</given-names>
            <suffix>Junior</suffix>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Bagano</surname>
            <given-names>Gabriela Oliveira</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Correia</surname>
            <given-names>Vitor Calixto de Almeida</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Lopes</surname>
            <given-names>Fernanda Oliveira de Andrade</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Souza</surname>
            <given-names>Thiago Menezes Barbosa de</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Fonseca</surname>
            <given-names>Leticia Lara</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Kertzman</surname>
            <given-names>Lara Queiroz</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Lacerda</surname>
            <given-names>Yasmin Falcon</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-6800-8100</contrib-id>
          <name>
            <surname>Rabelo</surname>
            <given-names>Marcia Noya</given-names>
          </name>
          <xref ref-type="aff" rid="aff2001">
            <sup>2</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-6910-1366</contrib-id>
          <name>
            <surname>Correia</surname>
            <given-names>Luis Claudio Lemos</given-names>
          </name>
          <xref ref-type="aff" rid="aff1001">
            <sup>1</sup>
          </xref>
        </contrib>
      </contrib-group>
      <aff id="aff1001">
        <label>1</label>
        <country country="BR">Brazil</country>
        <institution content-type="original">Escola Bahiana de Medicina e Sa&#250;de P&#250;blica (EBMSP), Salvador, BA - Brazil</institution>
      </aff>
      <aff id="aff2001">
        <label>2</label>
        <country country="BR">Brazil</country>
        <institution content-type="original">Hospital S&#227;o Rafael, Salvador, BA - Brazil</institution>
      </aff>
      <author-notes>
        <corresp id="c01001">Mailing Address: Luis C. L. Correia &#8226; Av. Princesa Leopoldina 19/402. Postal Code 40150-080, Salvador, BA &#8211; Brazil Email: luisclcorreia@gmail.com</corresp>
        <fn fn-type="con">
          <p>Author Contributions</p>
          <p>Conception and design of the research: Filgueiras PHC, Cerqueira Junior AM, Lopes FOA, Correia LCL; Acquisition of data: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Souza TMB, Fonseca LL, Kertzman LQ, Lacerda YF, Rabelo MN, Lopes FOA; Analysis and interpretation of the data: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Souza TMB, Rabelo MN, Lopes FOA; Statistical analysis: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Fonseca LL, Kertzman LQ, Lacerda YF, Correia LCL, Lopes FOA; Critical revision of the manuscript for intellectual contente: Filgueiras PHC, Cerqueira Junior AM, Bagano GO, Correia VCA, Souza TMB, Fonseca LL, Kertzman LQ, Lacerda YF, Rabelo MN, Correia LCL, Lopes FOA.</p>
        </fn>
        <fn fn-type="conflict">
          <p>Potential Conflict of Interest</p>
          <p>No potential conflict of interest relevant to this article was reported.</p>
        </fn>
      </author-notes>
      <abstract>
        <title>Abstract</title>
        <sec>
          <title>Background</title>
          <p>According to traditional diagnosis thinking, very elderly individuals are more predisposed to develop atypical symptoms in acute coronary syndromes.</p>
        </sec>
        <sec>
          <title>Objective</title>
          <p>To test the hypothesis that very elderly individuals are more predisposed to atypical chest pain manifestations due to obstructive coronary artery disease (CAD).</p>
        </sec>
        <sec>
          <title>Methods</title>
          <p>The Registry of Thoracic Pain includes patients admitted with acute chest pain. Firstly, the typicality index of this clinical manifestation was constructed: the sum of 12 symptom characteristics (8 typical and 4 atypical symptoms). In the subgroup of patients with coronary etiology, the typicality index was compared between octogenarian and non-octogenarian individuals. Statistical significance was defined by p&lt;0.05.</p>
        </sec>
        <sec>
          <title>Results</title>
          <p>958 patients were included in the registry, and 486 (51%) had a supposedly coronary etiology. In this group, 59 (12%) octogenarians (age 84&#177;3.5, 50% men) were compared to 427 patients aged &lt;80 (60&#177;12 years, 71% men). The typicality index in octogenarians was 3.42&#177;1.92, which is similar to that of non-octogenarians (3.44&#177;1.74; p=0.92 in univariate analysis and p=0.80 after adjustment for sex by analysis of variance &#8212; ANOVA). There was also no statistically significant difference when the sample was divided into median age (62 years; 3.41&#177;1.77 vs. 3.49 &#177; 1.77; p=0.61). There was no statistically significant linear association between age and typicality index (r=- 0.05; p=0.24). Logistic regression analysis for prediction of CAD in the general sample of 958 patients showed no interaction of typicality index with numeric age (p=0.94), octogenarians (p=0.22) or age above median (p=0.74).</p>
        </sec>
        <sec>
          <title>Conclusion</title>
          <p>In patients with acute chest pain of coronary etiology, advanced age does not influence the typical clinical presentation.</p>
        </sec>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>Elderly</kwd>
        <kwd>Chest Pain</kwd>
        <kwd>Acute Coronary Syndrome</kwd>
        <kwd>Prognosis</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <sec sec-type="intro">
        <title>Introduction</title>
        <p>Traditional clinical thinking indicates that elderly individuals are predisposed to atypical symptoms in acute coronary syndromes (ACS), a condition that may imply difficult diagnosis and delayed treatment.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> The plausible mechanisms for atypicality would be cognitive limitations, compromised communication or reduction of pain perception.<sup><xref ref-type="bibr" rid="B2">2</xref></sup></p>
        <p>However, although this traditional clinical thinking has as a possible physiological basis nociceptive alteration caused by depression and diabetes, which are more prevalent in older individuals, the vast majority of the studies found in the literature are retrospective and with a fairly variable and subjective definition of &#8220;pain typicality&#8221;. Therefore, it is still not clear whether, in fact, old age implies a different clinical presentation in the context of coronary syndromes.<sup><xref ref-type="bibr" rid="B3">3</xref> , <xref ref-type="bibr" rid="B4">4</xref></sup></p>
        <p>Thus, the present study proposes to test the hypothesis that very elderly individuals are more predisposed to atypical manifestations of chest pain of coronary etiology. As a primary analysis, the overall typicality of the clinical manifestation was compared between octogenarians and non-octogenarians in the subsample of patients with coronary etiology. This was followed by the analysis of the interaction between age and pain typicality in the prediction of coronary etiology in the sample of all etiologies of thoracic pain.</p>
      </sec>
      <sec sec-type="methods">
        <title>Methods</title>
        <sec>
          <title>Sample selection</title>
          <p>The Registry of Chest Pain is a sample of patients consecutively admitted to the Coronary Unit of a tertiary hospital from September 2011 to December 2017, primarily for chest discomfort, regardless of electrocardiographic abnormalities, necrosis markers or any other complementary examination showing the cause of the symptom.</p>
          <p>The selected sample aims to represent the target population of patients admitted to the coronary unit due to chest pain. Thus, all patients admitted during the study period were included in the study, with no subsample selection in this population. Admission to the coronary care unit was not influenced by the study protocol. The diagnostic probability was established at the discretion of the attending physicians.</p>
          <p>The study is in accordance with the ethical standards of resolution 510/2016 from the Ministry of Health, was approved by the Committee of Ethics in Hospital Research, and all subjects signed a free and informed consent.</p>
        </sec>
        <sec>
          <title>Characterization of thoracic discomfort</title>
          <p>Upon admission, information about the clinical presentation of chest discomfort was collected through a parameterized interview. This interview was done in a systematized way by trained investigators to avoid inducing patients&#8217; responses and to focus on the reproducibility of the method. The interview was parameterized to require objective yes/no answers. When the patient expressed doubt, the symptom was considered absent.</p>
          <p>Twelve symptom characteristics were evaluated, including 8 characteristics known as typical of angina (precordial pain, compressive aspect, irradiation to the left upper limb, irradiation to the neck, intensity classified by the patient as severe, discomfort on the previous days, presence of vagal symptoms, administration of sublingual medication followed by improvement of the symptom) and 4 characteristics considered atypical (change of pain according to the position, change with palpation of the site, change with movement of the arm and change with breathing).</p>
        </sec>
        <sec>
          <title>Symptom typicality index</title>
          <p>In order to quantify the overall typicality of the clinical manifestation, 1 point was assigned to each typical characteristic and 1 point was subtracted for each atypical characteristic (variation from -4 to +8, proportional to typicality).</p>
        </sec>
        <sec>
          <title>Definition of symptom etiology</title>
          <p>For the diagnostic evaluation, the patients were submitted to invasive coronary angiography or non-invasive provocative test (nuclear perfusion magnetic resonance imaging and single-photon emission computed tomography or dobutamine stress echocardiography), at the discretion of the attending cardiologist. For positive noninvasive tests, the patients had an angiography done for confirmation. Based on this diagnostic algorithm, obstructive coronary artery disease (OCAD) was defined as stenosis &#8805;70% at angiography. Coronary angiography without obstructive lesion or normal noninvasive test (ischemic defect size &lt;5% of left ventricular myocardium) indicated the absence of OCAD.</p>
        </sec>
        <sec>
          <title>Data analysis</title>
          <p>Normality of numeric variables was tested by histogram, comparing mean and median, and mainly considering the level of kurtosis and skewness &lt;3. Very elderly individuals were defined as age &#8805;80 years (octogenarians). Primary analysis was performed on the sample of patients with obstructive coronary disease, comparing the typicality index between octogenarians and non-octogenarians. In addition, each symptom characteristic was compared between the two groups. Numerical variables were expressed as mean and standard deviation, compared between the two groups by Student&#8217;s unpaired t-test. Categorical variables were expressed in proportions and compared using Pearson&#8217;s chi-squared test. Analysis of variance was done to compare the typicality index between groups after adjustment for gender. A linear association between typicality index and age was tested by Pearson&#8217;s correlation coefficient, based on a normal distribution of both variables. Multiple comparison was adjusted using the Bonferroni method.</p>
          <p>Then, the total sample of the registry (all patients admitted with acute chest pain, with and without coronary artery disease) was used and we evaluated the predictive capacity of the typicality index for obstructive coronary artery disease based on the area under the Receiver Operator Characteristic (ROC) curve. Next, we evaluated the age-modifying effect on the diagnostic accuracy (OCAD) of the overall pain typicality, in terms of interaction vs. age typicality in logistic regression, with age being inserted in three different ways: as a numerical variable, categorized into two groups (octogenarians or non-octogenarians) and categorized into two groups from the sample median. The software SPSS Version 23 was used. Statistical significance was defined as a two-tailed p value smaller than 0.05.</p>
        </sec>
        <sec>
          <title>Sample size calculation</title>
          <p>As for the sample size calculation, this was a study conducted on a previously existing sample as part of the Chest Pain Registry, a prospective collection of patients hospitalized for chest pain. This registry is used for various analyses and, in our methodology, before deciding to test any hypothesis, we evaluated the statistical power, which depends on the behavior of the variable in question. Thus, as the data had already been collected, we could use the standard deviation of the sample that would be used to evaluated whether the sample size was powered enough, an essential criterion to allow data analysis in our protocol.</p>
          <p>Thus, sample size was defined first, based on the distribution of the typicality index in the coronary disease sample. Considering a standard deviation of 1.7, it would be necessary for 36 octogenarians and 109 non-octogenarians to offer 80% power in detecting a 30% difference in the typical index by the Student&#8217;s t test.</p>
        </sec>
      </sec>
      <sec sec-type="results">
        <title>Results</title>
        <sec>
          <title>Sample characteristics</title>
          <p>Between September 2011 and December 2017, 958 individuals were included in the registry, and 486 (51%) had a supposedly coronary etiology. In this group, 59 octogenarians were compared to 427 non-octogenarians. The mean age of the octogenarians was 85&#177;3.4 years, including 56% men, compared to 60&#177;12 years, including 71% men, in the non-octogenarian group (p&lt;0.001). Octogenarian patients had a higher prevalence of clinically manifested left ventricular dysfunction (24% versus 8.7%, p&lt;0.001), triple vessel disease or left main coronary artery (41% versus 26%, p=0.01) and a lower prevalence of ST segment elevation acute myocardial infarction (25% versus 30%, p&lt;0.001). Mortality was higher in the older group (14% versus 2.1%, p&lt;0.001). The variables compared between the two groups are described in <xref ref-type="table" rid="t1001">Table 1</xref> .</p>
          <p>
            <table-wrap id="t1001">
              <label>Table 1</label>
              <caption>
                <title>&#8211; Clinical characteristics and comorbidities</title>
              </caption>
              <table frame="hsides" rules="groups">
                <colgroup>
                  <col/>
                  <col/>
                  <col/>
                  <col/>
                </colgroup>
                <thead>
                  <tr>
                    <th align="left" style="font-weight:normal"> </th>
                    <th>Age &lt;80 (n=427)</th>
                    <th>Age &#8805;80 (n=59)</th>
                    <th>p value</th>
                  </tr>
                </thead>
                <tbody>
                  <tr>
                    <td>Age (years)</td>
                    <td align="center">60&#177;12</td>
                    <td align="center">85&#177;3.4</td>
                    <td align="center">&lt;0.001</td>
                  </tr>
                  <tr>
                    <td>Male</td>
                    <td align="center">302 (71%)</td>
                    <td align="center">33 (56%)</td>
                    <td align="center">0.02</td>
                  </tr>
                  <tr>
                    <td>ECG ischemia</td>
                    <td align="center">279 (67%)</td>
                    <td align="center">37 (65%)</td>
                    <td align="center">0.80</td>
                  </tr>
                  <tr>
                    <td>Positive troponin</td>
                    <td align="center">274 (65%)</td>
                    <td align="center">49 (83%)</td>
                    <td align="center">0.005</td>
                  </tr>
                  <tr>
                    <td>ST-segment elevation infarction</td>
                    <td align="center">127 (30%)</td>
                    <td align="center">15 (25%)</td>
                    <td align="center">&lt;0.001</td>
                  </tr>
                  <tr>
                    <td>Diabetes mellitus</td>
                    <td align="center">161 (38%)</td>
                    <td align="center">27 (46%)</td>
                    <td align="center">0.23</td>
                  </tr>
                  <tr>
                    <td>Creatinine (mg/dl)</td>
                    <td align="center">1.0&#177;0.69</td>
                    <td align="center">1.1&#177;0.43</td>
                    <td align="center">0.12</td>
                  </tr>
                  <tr>
                    <td>Systolic blood pressure (mmHg)</td>
                    <td align="center">154&#177;31</td>
                    <td align="center">153&#177;36</td>
                    <td align="center">0.08</td>
                  </tr>
                  <tr>
                    <td>Heart rate (bpm)</td>
                    <td align="center">78&#177;18</td>
                    <td align="center">76&#177;19</td>
                    <td align="center">0.17</td>
                  </tr>
                  <tr>
                    <td>Previous coronary disease</td>
                    <td align="center">139 (33%)</td>
                    <td align="center">24 (41%)</td>
                    <td align="center">0.22</td>
                  </tr>
                  <tr>
                    <td>Previous myocardial revascularization</td>
                    <td align="center">37 (8.7%)</td>
                    <td align="center">7 (12%)</td>
                    <td align="center">0.40</td>
                  </tr>
                  <tr>
                    <td>Severe anatomical pattern*</td>
                    <td align="center">80 (26%)</td>
                    <td align="center">16 (41%)</td>
                    <td align="center">0.01</td>
                  </tr>
                </tbody>
              </table>
              <table-wrap-foot>
                <fn id="TFN1001">
                  <p>
                    <italic>*Catheterism with obstruction &#8805;70%; ECG: electrocardiogram.</italic>
                  </p>
                </fn>
              </table-wrap-foot>
            </table-wrap>
          </p>
        </sec>
        <sec>
          <title>Age and typicality of symptoms</title>
          <p>The typicality index of very elderly patients was 3.42&#177;1.92, which is similar to that observed in younger individuals (3.44&#177;1.74; p=0.92). Comparison of the typicality index remained non-significant (p=0.80) after adjusting for the gender difference between the groups ( <xref ref-type="fig" rid="f01001">Figure 1</xref> ).</p>
          <p>
            <fig id="f01001">
              <label>Figure 1</label>
              <caption>
                <title>&#8211; Boxplot of the typicality index for the octogenarian and non-octogenarian groups (p=0.92).</title>
              </caption>
              <graphic xlink:href="1678-4170-abc-116-06-1039-90089-gf01-en.tif"/></fig>
          </p>
          <p>There was no difference in the typicality index when the sample was divided into median age (62 years), being 3.41&#177;1.77 versus 3.49&#177;1.77 (p=0.61). Likewise, there was no correlation between typical index and age (r=- 0.05, p=0.24) ( <xref ref-type="fig" rid="f02001">Figure 2</xref> ).</p>
          <p>
            <fig id="f02001">
              <label>Figure 2</label>
              <caption>
                <title>&#8211; Scatter plot of typical index and age.</title>
              </caption>
              <graphic xlink:href="1678-4170-abc-116-06-1039-90089-gf02-en.tif"/></fig>
          </p>
          <p>The comparison between the 12 pain characteristics between octogenarians and non-octogenarians showed no significant difference after Bonferroni adjustment ( <xref ref-type="table" rid="t2001">Table 2</xref> ).</p>
          <p>
            <table-wrap id="t2001">
              <label>Table 2</label>
              <caption>
                <title>&#8211; Characteristics of thoracic pain</title>
              </caption>
              <table frame="hsides" rules="groups">
                <colgroup>
                  <col/>
                  <col/>
                  <col/>
                  <col/>
                  <col/>
                </colgroup>
                <thead>
                  <tr>
                    <th align="left" style="font-weight:normal"> </th>
                    <th style="font-weight:normal">Age &#8805;80</th>
                    <th style="font-weight:normal">Age &lt;80</th>
                    <th style="font-weight:normal">p value</th>
                    <th style="font-weight:normal">Adjusted p value (Bonferroni)</th>
                  </tr>
                </thead>
                <tbody>
                  <tr>
                    <td>Precordial pain</td>
                    <td align="center">348 (82%)</td>
                    <td align="center">48 (81%)</td>
                    <td align="center">0.98</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Compressive</td>
                    <td align="center">241 (56%)</td>
                    <td align="center">28 (48%)</td>
                    <td align="center">0.19</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Irradiation to upper left limb</td>
                    <td align="center">167 (39%)</td>
                    <td align="center">19 (32%)</td>
                    <td align="center">0.02</td>
                    <td align="center">0.24</td>
                  </tr>
                  <tr>
                    <td>Irradiation to the neck</td>
                    <td align="center">110 (26%)</td>
                    <td align="center">8 (14%)</td>
                    <td align="center">0.04</td>
                    <td align="center">0.48</td>
                  </tr>
                  <tr>
                    <td>Severe intensity</td>
                    <td align="center">253 (60%)</td>
                    <td align="center">39 (66%)</td>
                    <td align="center">0.33</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Discomfort on previous days</td>
                    <td align="center">67 (48%)</td>
                    <td align="center">14 (67%)</td>
                    <td align="center">0.10</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Vagal symptoms</td>
                    <td align="center">215 (50%)</td>
                    <td align="center">32 (54%)</td>
                    <td align="center">0.58</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Improvement with nitrate</td>
                    <td align="center">182 (43%)</td>
                    <td align="center">18 (31%)</td>
                    <td align="center">0.08</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Changes with position</td>
                    <td align="center">70 (16%)</td>
                    <td align="center">7 (12%)</td>
                    <td align="center">0.37</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Changes with palpation</td>
                    <td align="center">26 (6.1%)</td>
                    <td align="center">2 (3.4%)</td>
                    <td align="center">0.40</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Changes with arm movement</td>
                    <td align="center">29 (6.8%)</td>
                    <td align="center">3 (5.1%)</td>
                    <td align="center">0.62</td>
                    <td align="center">--</td>
                  </tr>
                  <tr>
                    <td>Pleuritic pain</td>
                    <td align="center">51 (12%)</td>
                    <td align="center">5 (8.5%)</td>
                    <td align="center">0.43</td>
                    <td align="center">--</td>
                  </tr>
                </tbody>
              </table>
            </table-wrap>
          </p>
        </sec>
        <sec>
          <title>Age-modifying effect on predictive capacity of pain typicality</title>
          <p>Analyzing the 958 patients in the registry, the typicality index presented an area under the ROC curve of 0.62 (95% CI = 0.58&#8211;0.65) for prediction of obstructive coronary artery disease. The logistic regression analysis showed no interaction of typicality index with numerical age (p=0.94), octogenarians (p=0.22) or age above the median of 62 years (p=0.74) ( <xref ref-type="fig" rid="f03001">Figure 3</xref> ).</p>
          <p>
            <fig id="f03001">
              <label>Figure 3</label>
              <caption>
                <title>&#8211; C-statistics of typicality index for prediction of obstructive coronary artery disease, considering all patients in the registry (958), ROC curve: 0.62 (95% CI = 0.58&#8211;0.65).</title>
              </caption>
              <graphic xlink:href="1678-4170-abc-116-06-1039-90089-gf03-en.tif"/></fig>
          </p>
        </sec>
      </sec>
      <sec sec-type="discussion">
        <title>Discussion</title>
        <p>The present study demonstrates that advanced age has no influence on the clinical presentation typicality in the context of acute coronary syndromes. In addition, the diagnostic value of the clinical manifestation is not influenced by age. As shown, even analyzing &#8220;old age&#8221; from various perspectives (dividing the sample between octogenarians and non-octogenarians, median age, 62 years, and still placing age as a continuous variable), none of the analyses suggested influence.</p>
        <p>The use of a &#8220;typicality index&#8221; allowed us to analyze overall pain typology, information complemented by the individual analysis of each characteristic. The so-called &#8220;index&#8221; is just the count of suggested symptoms minus unsuggested symptoms, a way to treat typicality as a numerical variable, avoiding the subjectivity of categorization in a typical or atypical clinical picture.</p>
        <p>Another important point of this study is that, for the definition of OCAD, we used coronary angiography, the gold standard exam, which implies a low risk of calibration bias.</p>
        <p>Previous studies that sought to study pain in older individuals with acute coronary syndrome showed controversial results.<sup><xref ref-type="bibr" rid="B2">2</xref> , <xref ref-type="bibr" rid="B3">3</xref> , <xref ref-type="bibr" rid="B5">5</xref></sup> It is found that in most of these studies the collection of pain characteristics was done retrospectively and from databases developed with other primary objectives.</p>
        <p>In 2001, Mehta et al.,<sup><xref ref-type="bibr" rid="B1">1</xref></sup> through a registry of Medicare beneficiaries in the USA, selected patients diagnosed of acute myocardial infarction and stratified the sample on the basis of age.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> In their study, the authors conclude that the initial presentation of chest pain decreased as the age increased. However, they do not show whether there is a statistical difference between the values, which makes this conclusion misleading.</p>
        <p>In a post-hoc analysis of the Internet Tracking Registry for Acute Coronary Syndromes (i*trACS), Han et al.<sup><xref ref-type="bibr" rid="B3">3</xref></sup> analyzed the clinical presentation in patients with ACS from two groups: age &#8805;75 years and &lt;75 years. They classified &#8220;typical presentation&#8221; as thoracic pain in crushing, compression or pressure, and concluded that only in the group of younger patients (age &lt;75 years) the typical presentation was associated with the diagnosis of ACS. In addition to the simplistic definition of &#8220;typical presentation,&#8221; the authors did not compare the two age groups diagnosed with ACS. In another post-hoc analysis, from the Gulf Registry of Acute Coronary Events (Gulf RACE), El-Menyar et al.<sup><xref ref-type="bibr" rid="B5">5</xref></sup> classified into three categories: typical, atypical and dyspnea, and found no age difference in the &#8220;typical&#8221; (55&#177;12) and &#8220;atypical&#8221; (57 &#177; 13) presentation groups. However, the authors attribute rather broad characteristics as being &#8220;typical&#8221;: &#8220;irradiation to the arm, shoulder, back, neck, jaw, epigastrium or other sites&#8221; which makes this classification subjective.</p>
        <p>We must recognize that despite satisfying the sample size calculation, our population of very elderly patients was small. In addition, our study was carried out in only one center and in a selected population, thus, the development of new studies in this context is necessary. We also recognize that this study was carried out in a tertiary hospital environment, so we must be careful when extrapolating its results to the primary care environment. Our population of greatest interest is that of patients admitted to the coronary care unit, a population where the challenge of diagnostic discrimination is greater, because there is greater homogeneity of symptoms (gray zone of probability). This being our target population, there was no selection bias. Finally, there is a plethora of possibilities and combinations of symptoms to be included in an analysis such as this. But here, we are not trying to create a predictor score for the etiology of pain; we are just comparing the very elderly and not very elderly regarding the &#8220;typicality load.&#8221; Regardless of whether we contemplate all possible symptoms, the hypothesis test for the &#8220;typicality load&#8221; is not compromised. We are just assessing whether there is a symptom gradient between these two groups.</p>
      </sec>
      <sec sec-type="conclusions">
        <title>Conclusion</title>
        <p>In patients with chest pain of coronary etiology, advanced age does not seem to influence the typical clinical presentation, suggesting that symptoms should be interpreted regardless of age.</p>
      </sec>
    </body>
    <back>
      <fn-group>
        <fn fn-type="other">
          <p>Study Association</p>
          <p>This article is part of the thesis of doctoral submitted by Ant&#244;nio Maur&#237;cio Cerqueira Junior, from Escola Bahiana de Medicina e Sa&#250;de P&#250;blica.</p>
        </fn>
      </fn-group>
      <fn-group>
        <fn fn-type="supported-by">
          <p><bold>Sources of Funding</bold>:  There were no external funding sources for this study.</p>
        </fn>
      </fn-group>
    </back>
  </sub-article>
</article>
