Factors associated with deterioration of health-related quality of life in multiple system atrophy: 1-year follow-up study.

The aim of this study was to identify the main contributors to the health-related quality of life (HRQoL) in multiple system atrophy with predominant parkinsonism (MSA-P) and to determine the usefulness of SF-36 in capturing the HRQoL changes over 1-year follow-up. A total of 45 MSA-P and 150 Parkinson's disease (PD) patients were studied. The hierarchical multiple regression analysis was conducted to identify predictors of the SF-36 total score. The magnitude of any change for the HRQoL over 1-year of follow-up, was calculated as an effect size. The average scores for each SF-36 domains, except for the bodily pain, were lower in MSA-P than in PD patients (p < 0.05). The most important predictors of HRQoL in MSA-P, were female gender, older age at onset, SCOPA-AUT score and UMSARS IV, which together with other selected clinical variables accounted for 84% of the variance in the total SF-36 score in the final model in hierarchical analyses. During the 1-year follow-up, the SF 36 was found capable of detecting changes in MSA-P. Our study provided some new insights into potential predictors of the HRQoL and its longitudinal changes in MSA-P, which should be considered when healthcare programs are developed.