AIMS Diabetes mellitus (DM) often coexists in elderly hypertrophic cardiomyopathy (HCM) patients; however, its impact on clinical outcomes is unclear.

METHODS We compared clinical outcomes according to the presence of DM in a nationwide HCM cohort.

RESULTS In 9,883 HCM subjects (mean age 58.5 ± 13.1, men 71.7%), 1,327 (13.4%) had DM. During follow-up (mean 5.9 ± 2.5 years), end-stage renal disease (ESRD) progression, coronary events (myocardial infarction, coronary revascularization), heart failure (HF), cardiovascular mortality, and all-cause mortality occurred in 80 (0.8%), 365 (3.7%), 1,558 (15.8%), 354 (3.6%), and 877 (8.9%) subjects, respectively. DM HCM subjects had significantly higher risks of ESRD progression (HR 3.49, 95% CI 2.20-5.54) and HF (HR 1.15, 95% CI 1.01-1.32) compared to non-DM HCM subjects, independent of age, sex, ischemic heart disease, atrial fibrillation, and other comorbidities. There was a tendency for greater risk of ESRD progression, HF, and all-cause death in subjects with more advanced stage of DM (p-for-trend < 0.05 for all). Insulin-treated DM was associated with the highest risk.

CONCLUSIONS DM HCM subjects have higher risk of ESRD progression and HF. Considering the extended life expectancy of HCM and increasing number of elderly HCM subjects, active surveillance and management of DM-related outcomes should be highlighted.