Objective: Myotonic dystrophy type 1 (DM1) is a rare autosomal dominant disorder with highly variable phenotypic expression. Some patients have diabetes mellitus, dyslipidemia, and/or arrhythmias, which are risk factors for stroke. However, the mechanism of stroke is poorly understood in patients with DM1. We studied the characteristics of risk-factor profiles for stroke associated with DM1. Patients and methods: We studied 77 patients with DM1 (45 men and 32 women) on the basis of the patients’ clinical histories and laboratory and genetic examination results. Results: The analysis showed that 26 patients (34%) had dyslipidemia, and 16 (21%) had diabetes. Arrhythmias were diagnosed in 46 patients (61%), including 11 (14%) with atrial fibrillation and 9 (12%) with conduction defects. Echocardiographic abnormalities were found in 28 patients (37%). Eight patients (11%) met the criteria for metabolic syndrome. We identified 2 patients (2.6%) with ischemic stroke caused by cardiogenic embolism among 77 patients with DM1. One had paroxysmal atrial fibrillation and sick sinus syndrome, and the other had cardiac dysfunction with an ejection-fraction of 35% and dyslipidemia. Both patients had highly expanded numbers of CTG repeats (1000 and 1500). Conclusion: To our knowledge, this is the first study to report a comprehensive analysis of risk-factor profiles for stroke in patients with DM1. Stroke is a relatively rare, but severe complication of DM1. Our results indicate that it is important to manage risk factors for stroke, especially cardiac involvement and arrhythmias.
Miho Sugie, Kazuma Sugie, Nobuyuki Eura, Naoki Iwasa, Tomo Shiota, Hitoki Nanaura,Tesseki Izumi and Satoshi Ueno