Characteristics of Risk-Factor Profiles Associated with Stroke in Patients with Myotonic Dystrophy Type 1.

Abstract

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.