Gender effect on cardiac involvement in Myotonic Dystrophy type 1 (DM1).

BACKGROUND cardiac involvement is observed in about 80% of subjects with Myotonic Dystrophy type1 (DM1) and is mainly characterized by cardiac conduction (CCA) and/or rhythm (CRA) abnormalities (CCRA), possibly leading to sudden cardiac death (SDC). OBJECTIVE to investigate whether the gender difference may influence the cardiac involvement and sudden cardiac death in DM1. METHODS we analyzed prevalence and incidence of cardiologic abnormalities in males versus females in 151 consecutive DM1 patients over 35 years of follow-up period, RESULTS: Fifty-five patients, 35 males (62.5%) and 20 females (42.5%) developed some type of CCRA during the follow-up period (mean 7.82 ± 6.21 years). CCRA overall, and specifically CCA, were significantly more frequent in males than in females (p=0.043 and p=0.031 respectively). CCRA progressed in 16 males (45.7%) and 6 females (30%). Twenty-four patients, 14 males (25.0%) and 10 females (21.3%) deceased during the follow-up. Nine of them, 6 males (10.7%) and 3 females (6.4%) had a SCD. After correction for MIRS progression, CTG expansion and follow-up duration, a higher prevalence of CCA was independently associated with male gender (p=0.039), but not independent association with gender was detected for CCRA overall, CRA and SCD prevalence, even if prevalence was higher in males than females. CONCLUSIONS the overall risk of occurrence of CCA in DM1 is significantly higher in males than females regardless of genetical background and disease severity and progression. As well, the data suggest similar impact of male gender also for CCRA overall, CCA and SCD even if not statistically significant.