Sex‐ and age‐based differences in the natural history and outcome of dilated cardiomyopathy

Aim: To evaluate the relationship between sex, age and outcome in dilated cardiomyopathy (DCM). Methods and results: We used proportional hazard modelling to examine the association between sex, age and all‐cause mortality in consecutive patients with DCM. Overall, 881 patients (290 women, median age 52 years) were followed for a median of 4.9 years. Women were more likely to present with heart failure (64.0% vs. 54.5%; P = 0.007) and had more severe symptoms (P < 0.0001) compared to men. Women had smaller left ventricular end‐diastolic volume (125 mL/m2 vs. 135 mL/m2; P < 0.001), higher left ventricular ejection fraction (40.2% vs. 37.9%; P = 0.019) and were less likely to have mid‐wall late gadolinium enhancement (23.0% vs. 38.9%; P < 0.0001). During follow‐up, 149 (16.9%) patients died, including 41 (4.7%) who died suddenly. After adjustment, all‐cause mortality [hazard ratio (HR) 0.61, 95% confidence interval (CI) 0.41–0.92; P = 0.018] was lower in women, with similar trends for cardiovascular (HR 0.60, 95% CI 0.35–1.05; P = 0.07), non‐sudden (HR 0.63, 95% CI 0.39–1.02; P = 0.06) and sudden death (HR 0.70, 95% CI 0.30–1.63; P = 0.41). All‐cause mortality (per 10 years: HR 1.36, 95% CI 1.20–1.55; P < 0.0001) and non‐sudden death (per 10 years: HR 1.51, 95% CI 1.26–1.82; P < 0.00001) increased with age. Cumulative incidence curves confirmed favourable outcomes, particularly in women and those <60 years. Increased all‐cause mortality in patients >60 years of age was driven by non‐sudden death. Conclusion: Women with DCM have better survival compared to men, which may partly be due to less severe left ventricular dysfunction and a smaller scar burden. There is increased mortality driven by non‐sudden death in patients >60 years of age that is less marked in women. Outcomes with contemporary treatment were favourable, with a low incidence of sudden death.