Clinical correlates of autonomic dysfunction in patients with Machado-Joseph disease

Background - Autonomic dysfunction is a usual feature of several neurological conditions characterized by either extra-pyramidal and/or peripheral damage, such as those seen in Machado-Joseph disease (MJD). Aims of the study - We used clinical evaluation and sympathetic skin responses (SSR) to assess autonomic function in a large series of patients with MJD. Methods - A total of 50 patients were enrolled in this study and all of them had the molecular confirmation of MJD by DNA genotyping. In addition, a group of 20 control subjects was included. Results - Overall, autonomic complaints were more frequent in patients than in control subjects, especially those related to the genitourinary and sudomotor systems. Eighteen patients (36%) presented abnormal SSR. Age at onset, duration of disease and length of expanded (CAG)(n) were not different between patients with and without dysautonomia. However, severe dysautonomia was significantly associated with polyneuropathic or parkinsonian phenotypes in patients with MJD. Conclusion - Autonomic symptoms are common, but possibly under recognized in patients with MJD; therefore, we believe that autonomic complaints should be sought in patients with MJD, especially in those with parkinsonian or polyneuropathic phenotypes.