Effects of comprehensive cardiac rehabilitation on functional capacity and cardiovascular risk factors in Brazilians assisted by public health care: protocol for a randomized controlled trial

Background: Cardiovascular Disease (CVD) is the leading burden of disease worldwide. Moreover, CVD-related death rates are considered an epidemic in low- and middle-income countries (LMICs). Research shows that cardiac rehabilitation (CR) participation reduces death and improves disability and quality of life. Given the growing epidemic of CVD in LMICs and the insufficient evidence about CR programs in these countries, a Randomized Control Trial (RCT) in Latin America is warranted. Objective: To investigate the effects of comprehensive CR on functional capacity and cardiovascular risk factors. Method: The design is a single-blinded RCT with three parallel arms: comprehensive CR (exercise + education) versus exercise-based CR versus wait-list control (no CR). The primary outcome will be measured by the Incremental Shuttle Walk Test. Secondary outcomes are risk factors (blood pressure, dyslipidemia, dysglycemia, body mass index and waist circumference); tertiary outcomes are heart health behaviors (exercise, medication adherence, diet, and smoking), knowledge, and depressive symptoms. The CR program is six months in duration. Participants randomized to exercise-based CR will receive 24 weeks of exercise classes. The comprehensive CR group will also receive 24 educational sessions, including a workbook. Every outcome will be assessed at baseline and 6-months later, and mortality will be ascertained at six months and one year. Conclusion: This will be the first RCT to establish the effects of CR in Latin America. If positive, results will be used to promote broader implementation of comprehensive CR and patient access in the region and to inform a larger-scale trial powered for mortality.