Female Sex Is Associated with Worse Prognosis in Patients with Hypertrophic Cardiomyopathy in China

Background: Sex plays an important role in the clinical expression and prognosis of various cardiovascular diseases. This study was designed to observe the effects of sex on hypertrophic cardiomyopathy (HCM). Methods and Results: A total of 621 unrelated patients with HCM without heart failure (460 males) were enrolled from 1999 to 2011. Compared to male patients, at baseline female patients were older at diagnosis (49.6 +/- 17.2 years vs. 46.7 +/- 14.4 years, P = 0.033), and had greater frequency of left ventricular outflow tract obstruction (72/161, 44.7% vs. 149/460, 32.4%, P = 0.005). During the average four year follow-up period (range 2-7 years), survival analysis showed that the incidences of mortality from all causes, cardiovascular death and progression to chronic heart failure were greater in women than in men (P = 0.031, 0.040 and 0.012, respectively). After adjustment for multiple factors that may confound survival and cardiac function, female sex remained an independent risk factor for all-cause mortality, cardiovascular death, and chronic heart failure [hazard ratio (HR) 2.19, 95% confidence interval (CI) 1.21-3.95, P = 0.010; HR 2.19, 95% CI 1.17-4.09, P = 0.014; HR 1.73, 95% CI 1.12-2.69, P = 0.014, respectively] in HCM patients. Subgroup analysis revealed that female sex as a risk factor was identified only in patients younger than 50 years old (P = 0.011, 0.011 and 0.009, respectively), but not for those 50 years or older. Conclusion: Our results suggest that female sex is associated with worse survival and heart failure in HCM patients. Further studies are required to determine whether female hormones modify the clinical expression and prognosis of HCM.