Racial, Sex, and Age Disparities in Cardiomyopathy Etiology: A Social Determinant Analysis of 366 Cardiac Patients

BACKGROUND: Inequities in heart failure persist across race, sex, and age, but etiology-specific patterns in cardiomyopathies remain underexplored. We examined disparities across cardiomyopathy etiologies using a social determinants of health (SDoH) lens. METHODS: We analyzed 366 left ventricular tissue samples from the GEO dataset GSE141910, focusing on cardiomyopathy subtypes: dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), peripartum cardiomyopathy (PPCM), and nonfailing controls. Demographics included race (African American, Caucasian), sex, and age. We compared distributions using χ² or Fisher's exact tests and assessed age differences with t-tests/analysis of variance. RESULTS: African Americans showed a 1.69-fold higher prevalence of DCM vs. Caucasians (62.1%, n = 77 vs. 36.8%, n = 89; χ² = 27.101, df = 2, p < 0.001, Cramér's V = 0.272) and presented 5.9 years earlier (48.9 ± 12.9 years, n = 77 vs. 54.8 ± 7.1 years, n = 89; p < 0.001, Cohen's d = -0.572). HCM was 13.8-fold more common in Caucasians (11.2%, n = 27 vs. 0.8%, n = 1; Fisher's exact p < 0.001). PPCM occurred exclusively in women and was nearly twofold more frequent among African Americans (62.5%, n = 5 of 8 PPCM cases), who also presented younger than Caucasians (29.5 years, n = 2 vs. 37.2 years, n = 4). Male sex was associated with higher DCM prevalence (51.5%, n = 100 vs. 38.4%, n = 66; χ² = 13.845, df = 3, p = 0.016, Cramér's V = 0.194) and predominated in HCM (60.7%, n = 17). Intersectional analyses revealed disproportionate burden among younger African Americans; among DCM patients <45 years, 71.4% (n = 15 of 21) were African Americans. CONCLUSIONS: Cardiomyopathy etiology is associated with systematic demographic patterns. African Americans are more likely to experience earlier onset and greater DCM burden, while Caucasians exhibit markedly higher HCM prevalence. Male sex is disproportionately represented in DCM and HCM. These findings are consistent with SDoH-driven inequities and underscore the need for earlier detection, equity-centered prevention, and improved access to specialized diagnostics and therapies.