[Myotonic dystrophy type 1: a series of 107 patients].

INTRODUCTION

Myotonic dystrophy type 1 is the most common muscular dystrophy in adults. It is a genetic disorder of autosomal dominant inheritance and one of its most striking features is its multi-systemic involvement with a wide clinical phenotype.

PATIENTS AND

METHODS

Data from 107 patients with a genetically confirmed diagnosis of the disease were retrospectively analysed from the database of a national reference division for neuromuscular diseases. Demographic and clinical data were collected over a 7-year period.

RESULTS

The most frequent age of symptom onset was adulthood (66.4%). 35% showed exclusive distal weakness and a majority (63.6%) had clinical myotonia. Only 10 patients lacked neuromuscular symptoms at diagnosis and up to 9.5% were restricted to a wheelchair. The implantation of a pacemaker or cardioverter-defibrillator was conducted in 16 patients but no sudden cardiac death was detected. A venous thromboembolic disease incidence rate of 5.6 cases per 1000 patient-year was identified. More than half of the patients (54%) in the series developed respiratory failure. 13 patients died during the follow-up period, with respiratory failure being the main cause of death.

CONCLUSIONS

The follow-up and clinical management of patients with DM1 should be multidisciplinary. In our series, the main cause of morbidity and mortality was respiratory disorders, whereas the incidence of cardiac disorders was lower. In addition, there is a notable frequency of complications derived from falls, which can have serious consequences. Finally, a higher than expected incidence of thromboembolic events was identified, which deserves further study in other cohorts of patients.