Blacks with Hypertrophic Cardiomyopathy Have Lower Quality of Life and Exercise Capacity Than Whites

INTRODUCTION: Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disorder. There is a paucity of literature in blacks with HCM overall and specifically on quality of life and functional capacity. Symptom experience in this population is conceptualized as the integration of quality of life, functional capacity and NYHA class. OBJECTIVE: This study aimed to examine differences in functional capacity, quality of life and NYHA between blacks and whites with HCM. METHODS: The study was a secondary analysis of a dataset of consecutively enrolled patients with HCM, referred for care at a large HCM specialty center. Data analyzed included demographics, co-morbidities, Minnesota Living with Heart Failure Questionnaire (MLWHFQ) scores on quality of life (QOL), age-adjusted functional capacity measured by METs achieved on symptom limited stress echocardiography, and NYHA class. RESULTS: Blacks comprised 13.1% of the total sample of 434 subjects. Women were underrepresented in both groups, 27 (47.4%) blacks, 153 (40.6%) whites. Blacks were younger, 54.6 (13.4) vs 62.5 (14.8) years old, p<0.001. Both groups had similar number of co-morbidities. Blacks had higher levels of Class II obesity (BMI 35-39.9); there were no differences in prevalence in HTN or other co-morbid conditions. NYHA class was similar between groups, though blacks were less likely to be asymptomatic (NYHA class I). Blacks had higher mean MLWHFQ scores, 31.2 (27.2) vs 23.9 (22.1), p=0.04 reflecting poorer QOL than whites. Blacks were also more likely to have a functional capacity objectively measured as METs that was “below average for age” than whites, 25 (64.1%) vs 115 (47.7%), p=0.029. None of the blacks (0%) in this cohort had an “excellent for age” functional capacity compared to 19 (7.9%) of whites p= 0.035. CONCLUSIONS: Despite similar NYHA class, co-morbidities and significantly younger age, blacks with HCM had poorer QOL and worse objectively measured functional capacity than whites with HCM. These findings suggest that the symptom experience may differ between blacks and whites with HCM. Research with sample sizes including more blacks with HCM and more precise measurement of symptoms is needed to generalize these results and examine potential contributing factors.