Prevalence and Characterization of the Hypertrophic Cardiomyopathy Phenotype Assessed by Echocardiography in an Adult Brazilian Population: The ELSA-Brasil Study

Background Hypertrophic cardiomyopathy (HCM) is a genetically inherited cardiac disease with significant clinical impact. Although its epidemiology is well described in developed countries, the prevalence of HCM in Latin American populations remains poorly defined. Objective To estimate the prevalence of the HCM phenotype and describe its clinical and echocardiographic characteristics in a large adult Brazilian cohort. Methods The ELSA-Brasil study is a multicenter cohort including 15,105 active and retired public servants aged 35-74 years at baseline. Comprehensive clinical data collection was conducted at each investigation center. Baseline echocardiographic examinations were reviewed, and participants were classified as having Definitive HCM if established diagnostic criteria were met. The prevalence of HCM and its 95% CI were calculated. Individuals meeting borderline criteria were classified as Possible HCM. A p-value < 0.05 was considered statistically significant. Results Among 3,267 participants who underwent echocardiography at baseline (mean age 64 ± 9 years; 53% women), five individuals met diagnostic criteria for HCM, of whom 80% were women. The estimated prevalence of HCM was 0.15% (95% CI, 0.05%-0.36%). Three participants exhibited a septal hypertrophy phenotype, and all cases of Definitive HCM showed abnormal electrocardiographic findings. A total of 19 additional participants were classified as Possible HCM, with no statistically significant differences compared with the Definitive HCM group. Conclusion The prevalence of HCM in this Brazilian cohort was approximately 1.5 per 1,000 individuals, consistent with rates reported in other populations. Most cases of HCM occurred in women and were frequently associated with metabolic conditions. These findings provide novel data on the epidemiology and clinical profile of HCM in Brazil and highlight the need for further research on genetic cardiomyopathies in Latin America.