More than 64 million people live with heart failure (HF) in the world.¹ Due to its progressive nature, HF is characterized by high mortality in the advanced phase, and its prognosis varies widely according to the population studied.¹ According to population-based studies, after the diagnosis of HF, survival estimates at 5 and 10 years are 50% and 10% respectively.^{2 - 6} The risk of mortality for HF patients is twice of people without the disease.^{7 - 9} A recent cohort study of patients diagnosed with HF from 2000-2017 in the United Kingdom reported only a modest improvement in survival in the 21^st century.^{10 - 12}

In a review published in 2002, McMurray and Stewart¹¹ conducted a comparison of HF mortality with different types of cancer. The authors showed that HF killed more patients than breast, prostate, bladder, bowel, and ovarian cancer. Only lung cancer was more malignant than HF.¹¹ Mamas et al.,¹² in a more recent review, showed that the statement presented by McMurray and Stewart remains valid until today, allowing us to conclude that HF is a more malignant disease than many types of cancer.¹² However, although the international literature is abundant in articles addressing HF mortality, there are no data to support that HF mortality is higher than cancer mortality in Brazil.

The primary objective of this study was to compare the number of in-hospital deaths due to HF and selected cancer diseases in Brazil between 2005 and 2015. Secondary objectives were to compare the number of hospital admissions due to HF and selected cancer diseases in Brazil between 2005 and 2015; and to compare in-hospital mortality rates from HF and selected cancer diseases in Brazil between 2005 and 2015.

The data were aggregated for calculations of mortality and hospitalization, in absolute numbers and rates, by disease and year of occurrence. Each event (hospitalization, death and in-hospital death) was coded according to the ICD-10 classification (after accounting for ill-defined or undefined causes of death) and the aggregated groups of causes were analyzed considering the year of occurrence (2005 to 2015).

For death events, a redistribution method of ill-defined causes of death (Chapter XVIII of the ICD-10 - Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified) was used as described by Soares et al.¹⁵ Undefined causes of death were redistributed using the proportion of each defined cause except for external causes (which were assumed to contribute to a small proportion of in death records). These reclassified death records were summed to the absolute number of deaths initially coded with eligible ICD-10 codes for the study.

Data were then descriptively compared year by year between selected diseases using graphs.

As a descriptive study, all data on death and hospitalization that met the eligibility criteria were organized and stored in a Microsoft Excel spreadsheet. Thus, sample size calculation was not applicable.

Due to the nature of the study – a retrospective database study without patient-level data – information about participants is not disclosed.

Table 1 presents the absolute number of hospitalizations for different types of cancer and HF from 2005 to 2015. The frequency of hospitalization for HF was higher compared with various types of cancer.

Table 2 shows the number of patients who died during hospitalization for cancer or HF treatment.

We observed a higher number of in-hospital mortality for HF compared with selected types of cancer over the study period. Undefined causes of death contributed to an average of 8.13% of deaths in the period.

Table 3 shows the percentage of in-hospital mortality of patients with HF and with different types of cancer. HF mortality has increased progressively in these eleven years. Patients with HF hospitalized for compensation had an average mortality in of 11.08%, higher than breast cancer (9.60%) and prostate cancer (10.32%) and lower than other types of cancer.

Several authors have called attention to the fact that the mortality of HF patients is high and more pronounced than of patients with some types of cancer.^{13 , 14} In Brazil, the mortality of patients with HF is also high, particularly when compared with mortality rates described in developed countries, but there are no data comparing mortality from HF with cancer in our country. In this article, we made this comparison using data from DataSUS.^{15 - 17}

The comparative analysis of hospital admissions for HF with admissions for the most prevalent types of cancer revealed significantly higher numbers of patients hospitalized due to HF than cancer ( Table 1 ). Besides, the number of patients who died from HF was significantly higher than those who died from different types of cancer ( Table 2 ). In addition, considering in-hospital mortality, we may say that HF was more malignant than breast cancer and prostate cancers ( Table 3 ), as mean mortality rate of patients hospitalized due to acute HF (11.08%) was higher than breast (9.60%) and prostate cancers (10.32%).

In Latin America, HF is the leading cause of hospitalization, with rehospitalization rates of 33%, 28%, 31%, and 35% at 3, 6, 12, and 24 to 60 months of follow-up, respectively.^{18 , 19} Despite treatment advances, HF still has a poor prognosis, with high mortality rates. Five-year mortality rate for HF was estimated at approximately 50%.²⁰ In Latin America, it is estimated a one-year mortality rate of 24.5%, and in-hospital mortality rate of 11.7%.¹⁹ Brazilian registry data indicate an in-hospital mortality rate of 12.6%.²¹

As shown in previous studies in developed countries,^{14 , 20 , 22} HF can be associated with worse outcomes than some types of cancer. Askoxylakis et al.,²⁰ conducted a systematic review of the literature and noted a five-year survival of approximately 43% for all cancer types and 26-52% for HF, showing that HF in some settings is as deadly as some cancers, and even worse as compared with cancers like breast cancer (73-89%), prostate cancer (50-99%) and colorectal cancer (43-63%).²⁰ Using a retrospective approach, Stewart et al.,²² identified that the annual incidence of first-ever hospitalization for HF was higher than for cancer in Sweden: 484 versus 373 (lung, colorectal, prostate, and bladder cancer combined) per 100,000 men and 470 versus 350 (lung, colorectal, bladder, breast, and ovarian cancer combined) per 100,000 among women aged > 20 years. The authors also observed that the 30-day and five-year mortality rates were comparable between HF and cancer, and that during the 10-year follow-up period, HF was associated with more premature life-years lost than all common forms of cancer in men but not in women.²² Mamas et al.,¹² conducted an analysis of survival rate comparing HF with some forms of cancer. The authors’ findings indicated that HF had significantly worse five-year survival rate (55.8%) than prostate cancer (68.3%) and bladder cancer (57.3%), but significantly better than lung cancer (8.4%) and colorectal cancer (48.9%). In women, HF mortality outcome was worse (49.5%) than breast cancer (77.7%), but better than colorectal cancer (51.5%), lung cancer (10.4%), and ovarian cancer (38.2%).¹⁴

Our data confirm the described in Latin America and in the world^{14 , 20 , 22} regarding high rates of mortality from HF as compared with some cancers These data reinforce the need to recognize HF as a priority condition in Brazil, mainly by health system managers and policy makers, but also by the general population. Besides the magnitude of the disease burden in terms of deaths and hospitalizations, the decreasing rates observed in temporal series highlight that HF potentially responds to improvement in care with better outcomes that are relevant for both patients and the health care system, once hospitalization is the main cost driver in HF.^{22 , 23}

Since the data used in this analysis were representative of all the death certificates and hospitalization claims from the Brazilian public health care system during the 2005-2015 period, it is possible to assume that the findings are applicable to the national setting for mortality data and for the public health care system for hospital admission data.

It is important that physicians become aware of these data, to try to make an earlier diagnosis of HF and provide earlier treatment using the best evidence, and thereby modify the natural history of the disease.

It is worth remembering that the CONSENSUS study showed that, although it was possible to modify the course of HF, the mortality remained high (44%) in the control group in the first six months and in the first year (52%). The prescription of enalapril reduced mortality to 26% in the first six months and to 36% at the end of the first year.²³ With the introduction of beta-blockers, mineralocorticoid receptor antagonists, angiotensin receptor antagonists and, more recently an angiotensin receptor neprilysin inhibitor (ARNI), it is possible to substantially reduce the mortality of patients with insufficiently treated HF.^{24 - 26}

An interesting point often discussed in Brazilian scientific meetings is the interpretation of the recent reduction in the number of hospitalizations for HF per year, as indicated by the SUS data. Some presentations interpret such decrease as a result of better management of the cases, without taking into account, however, the significant reduction in the number of SUS beds ( Table 4 ) in recent years. With a smaller number of beds, physicians are pressured to admit only the most serious patient who will have the highest mortality, even with the best treatment available.

We can conclude that HF alone promotes more hospitalizations and deaths than some types of cancer. The mortality of patients with HF was higher than the one observed in patients with breast or prostate cancer, a result similar to other studies around the world. This concept of HF malignancy should be better disseminated so that more attention would be paid to patients with the syndrome, as its prognosis varies with treatment (e.g. timing and dosage, use of neurohormonal blockers), according to national guidelines.

The results of this analysis indicate that HF causes a significant burden to the health care system and the society, in terms of mortality and hospitalization. This burden is comparable or even worse than that caused by some types of cancer. It is urgent that health managers, policy makers and the society need to prioritize the early diagnosis, prevention and treatment of HF, when deciding about resource allocation in the health care system