Sex differences in disease progression and arrhythmic risk in patients with arrhythmogenic cardiomyopathy

AIMS: We aimed to assess sex-specific phenotypes and disease progression, and their relation to exercise, in arrhythmogenic cardiomyopathy (AC) patients. METHODS AND RESULTS: In this longitudinal cohort study, we included consecutive patients with AC from a referral centre. We performed echocardiography at baseline and repeatedly during follow-up. Patients’ exercise dose at inclusion was expressed as metabolic equivalents of task (MET)-h/week. Ventricular arrhythmia (VA) was defined as aborted cardiac arrest, sustained ventricular tachycardia, or appropriate therapy by implantable cardioverter-defibrillator. We included 190 AC patients (45% female, 51% probands, age 41 ± 17 years). Ventricular arrhythmia had occurred at inclusion or occurred during follow-up in 85 patients (33% of females vs. 55% of males, P = 0.002). Exercise doses were higher in males compared with females [25 (interquartile range, IQR 14–51) vs. 12 (IQR 7–22) MET-h/week, P < 0.001]. Male sex was a marker of proband status [odds ratio (OR) 2.6, 95% confidence interval (CI) 1.4–5.0, P = 0.003] and a marker of VA (OR 2.6, 95% CI 1.4–5.0, P = 0.003), but not when adjusted for exercise dose and age (adjusted OR 1.8, 95% CI 0.9–3.6, P = 0.12 and 1.5, 95% CI 0.7–3.1, P = 0.30, by 5 MET-h/week increments). In all, 167 (88%) patients had ≥2 echocardiographic examinations during 6.9 (IQR 4.7–9.8) years of follow-up. We observed no sex differences in deterioration of right or left ventricular dimensions and functions. CONCLUSION: Male AC patients were more often probands and had higher prevalence of VA than female patients, but not when adjusting for exercise dose. Importantly, disease progression was similar between male and female patients.