Sarcopenia is defined as a progressive and generalized loss of skeletal muscle mass and function (i.e., muscle power, muscle strength, and physical performance).^{1 - 5} Since 2016, it has been recognized as a disease.⁶ People aged 50 years and older lose 1% of skeletal muscle mass, 2% of gait speed, and 1.9 to 5.0% of handgrip strength per year,^{7 , 8} and these variables have been used for the assessment of sarcopenia by renowned organizations.⁹ However, the cause and pathogenesis of sarcopenia are not fully understood; the target in sarcopenia treatment is to improve patient survival and quality of life.

Sarcopenia is highly prevalent in older adults,¹⁰ and the incidence of arterial hypertension is over 70% in this population. Data from population studies have shown that the prevalence of hypertension is increased in patients with sarcopenia.¹¹

Hypertension pharmacotherapy usually consists of single therapy or a combination of different medications. The most used medication classes are angiotensin II receptor blockers (ARBs), angiotensin-converting enzyme inhibitors (ACEIs), diuretics (DIUs), calcium channel blockers, and beta-blockers.¹²

Several researchers have investigated the contribution of different medications to the treatment of sarcopenia, including the role of the renin angiotensin system in skeletal muscle and functional capacity.¹³ The renin-angiotensin system modulates muscle function, and ARBs and ACEIs have been shown to remodel the skeletal muscle, protecting against atrophy by transforming growth factor beta.¹⁴ ACEIs have been used to improve skeletal muscle function, as they increase endothelial function, promote angiogenesis, and have anti-inflammatory effects that increase mitochondrial content and insulin-like growth factor values.^{15 - 17}

Meanwhile, the chronic use of loop DIUs, one of the classes of medication used in the treatment of hypertension, has been shown to potentially cause loss of muscle function by suppressing the sodium-potassium pump. In patients with renal failure,¹⁸ heart failure, and hypertension, treatment with DIUs impairs the sodium-potassium pump function. Muscle biopsy specimens of patients have shown decreased intracellular potassium and increased intracellular sodium concentration.¹⁹

The present study aimed to evaluate the possible associations between drugs used for hypertension and the presence or absence of sarcopenia in the older adult. Handgrip strength, skeletal muscle mass, and physical performance measure were used to determine the level of sarcopenia, following the European Working Group on Sarcopenia in older people criteria.²⁰

Table 1 shows characteristics of participants and medications used to treat hypertension. Most patients used ARBs + DIUs (n=119; 70,4%), followed by calcium blockers (n=22; 13.0%), ACEIs (n=14; 8,3%), and beta-blockers (n=13; 7,7%). Table 1 also lists the number of classes of medication used by the patients.

Figure 1 shows the mean number of patients according to the level of sarcopenia (absent; probable; confirmed; and severe) and age (a), handgrip strength (b), muscle mass index (c), and gait speed (d). The results revealed a difference between men’s age in the “probable sarcopenia” group compared with “absent” group, and none of the men showed confirmed or severe levels of sarcopenia. Individuals with sarcopenia reported lower handgrip strength, and those with severe sarcopenia had lower muscle mass index and lower gait speed.

Regarding the drugs used to treat hypertension, only seven individuals did not use ARBs or DIUs. In addition, of the 31 individuals who were diagnosed with sarcopenia, 25 used ARBs, DIUs, or a combination thereof. We chose to study the association between sarcopenia and the drugs used for hypertension treatment in the 53 individuals who used only ARBs (n = 17), DIUs (n = 13), or the combination of ARBs + DIUs (n = 23). Distribution of these combinations is illustrated in Figure 2 .

The variables “type of medication” and “degree of sarcopenia” were then displayed in a two-way contingency table ( Table 2 ). The Fisher’s exact test indicated that these two categorical variables were associated (p-value: 0.0466). As such, correspondence analysis was carried out to investigate the nature of this association. This multivariate technique decomposes the chi-squared statistic associated with a contingency table into orthogonal factors, ordered by degree of variation in the data set. For instance, if the first two factors accounted for most (say, 70%) of the variation, a simple scatter plot of these factors should be sufficient for identifying the categories of variables that most contributed to the association. The scatter plot of the variables “type of medication” and “degree of sarcopenia” is shown in Figure 3a . Two groups of categories contributed most to the association: DIUs associated with probable sarcopenia, and absence of sarcopenia associated with ARBs and ARBs + DIUs. However, as the first two factors accounted for only 52% of the variation in the contingency table, we chose to consider a third factor, to confirm if this trend would continue. The first three factors explained 72% of the variation and were then used to calculate Euclidean distances between categories. Subsequently, the Ward’s clustering method²⁷ was applied to the categories. The resulting dendrogram is shown in Figure 3b . Again, it suggested that DIUs were associated with probable sarcopenia, whereas absent sarcopenia was associated with ARBs or ARBs + DIUs.

Sarcopenia is a disease (ICD-10- M62.84) that affects over 10,000 older adults worldwide, and 43% of those aged 80 or above. Recently, sarcopenia has become the focus of intensive studies, and progress has been made toward a better understanding of its etiology and associated causes. Considering the consequences of sarcopenia and the aging of the world’s population, research should continue to refine strategies for diagnosis and prevention of sarcopenia in hypertensive older adults. Falls, functional decline, and fragility are known to cause adverse health effects in the elderly population.⁹ Only 5.3% of frail persons are not sarcopenic. Several strategies must be adopted to minimize this problem, and one of them is to identify possible drugs involved in this process.²⁹

Taking into account the aging of the Brazilian population³⁰ – the focus of the present study – researchers should consider building a consensus regarding the diagnosis of sarcopenia in Brazil. There are guidelines on sarcopenia for the Brazilian population; the present study was based on the European Consensus²⁰ and the SMM index proposed by Janssen et al.²⁵

In our study population, although age range was not different between women with different levels of sarcopenia, mean age was significantly different between men with absent and probable sarcopenia. The prevalence of sarcopenia in older adults aged between 60 and 70 years varies from 5% to 13%, and in those aged 80 years and older, from 11% to 50%, according to SMM.³¹

Meanwhile, mean values of the handgrip test, muscle mass, and gait speed results confirmed that handgrip strength is a good parameter for classifying sarcopenia. Studies have used the handgrip strength test for diagnosing sarcopenia,^{2 , 5 , 9} and showed it has good intra- and inter-observer reliability and can be used in clinical practice.^{32 , 33} Our data revealed that muscle mass index and gait speed seemed to act as confounding factors, as the absent and probable sarcopenia groups showed different values. Thus, both parameters may be best used after a first screening with handgrip strength.

Coelho-Junior et al.,³⁴ also reported an increased prevalence of hypertension in individuals with sarcopenia. In our study, most patients (122 out of 129) used ARBs or DIUs. A possible contributing factor to this that these medications are provided for free by the public health services in Brazil.

The scatter plot showed the association between the type of medication and degree of sarcopenia, and two associations seemed to contribute most to this, the association between DIUs and probable sarcopenia, and the association between absence of sarcopenia and ARBs and ARBs + DIUs. This result was confirmed by the Ward’s clustering algorithm.

Treatment with ARBs can have protective effects against muscle loss, since angiotensin II increases superoxide production,³⁵ reduces the autocrine insulin-like growth factor-1 signaling,³⁶ decreases mitochondrial function,³⁵ and increases apoptosis³⁷ in skeletal muscles, leading to muscle loss. In humans (cardiovascular patients) and in a rat model for heart failure associated with muscle atrophy and with increase in fatigability, ARBs provided protective effects by reversing most of the molecular markers of skeletal muscle loss.³⁸ Brown et al.,³⁹ reported that the use of ARBs instead of ACEIs for the treatment of hypertension could prevent mobility disability in older adults, especially in those at risk for decreased mobility and loss of physical independence. Further studies are necessary to investigate if the molecular and biochemical effects are reflected in worse physical performance and reduction in muscle mass.

Regarding the use of DIUs, the present study showed a significant association between DIUs and sarcopenia. A study⁴⁰ has shown that in patients with renal failure, heart failure, and hypertension, treatment with DIUs impaired the sodium-potassium pump function. Indeed, muscle biopsy specimens of patients demonstrated a reduction in intracellular potassium concentration and increase in intracellular sodium.¹⁹ In vitro studies using skeletal muscle cells have shown that loop DIUs block the Na+-K+-2Cl-cotransporter activity, thereby suppressing skeletal muscle differentiation.¹⁸ Hanai et al.,⁴¹ also reported that the use of a higher dose of loop DIUs was associated with a faster decrease in SMM in patients with liver cirrhosis, independent of the severity of liver disease, suggesting that loop DIUs are one of the risk factors of sarcopenia.

Our study has some limitations that need to be considered. First, there was a small number of individuals that used only DIUs. Second, the frequency and time of use of drugs were not evaluated with respect to sarcopenia level. Third, the diagnosis of sarcopenia was made based on the European Consensus. It is necessary to confirm the reproducibility of this consensus in the Brazilian population.

In conclusion, age of elderly women with sarcopenia was not different from that of elderly women without sarcopenia. The handgrip strength test was a good method for diagnosing sarcopenia. The use of DIUs was associated with increased risk of sarcopenia in hypertensive older adults. Results of the present study is a starting point for health professionals to carefully consider antihypertensive prescription to elderly patients.