Body mass index and severity of parkinsonism in multiple system atrophy

Patients with neurodegenerative disorders lose body weight as their diseases progress. In Parkinson’s disease (PD), however, autonomic dysfunction is associated with increased body mass index (BMI). We investigated the correlation between BMI, clinical features, and autonomic dysfunction in patients with multiple system atrophy with predominant parkinsonism (MSAP). BMI, clinical features, cardiac 123Imetaiodobenzylguanidine scintigraphy (MIBG), Hoehn and Yahr (H-Y) stage, and the coefficient of variation of the R-R interval (CVRR) were analyzed in 50 patients with MSA-P. BMI showed no significant correlation with MIBG parameters or CVRR. On the other hand, the H-Y stage was significantly negatively correlated with BMI. Higher H-Y stage indicates a more severe neuromuscular state in MSA-P and is considered to be related to higher energy expenditure and decrease of BMI. Patients with MSA-P lose weight as the disease progresses. This is the first report indicating a significant correlation between disease severity and BMI decrease in MSA.