Factors Associated With the Response to Exercise in Patients With Parkinson's Disease

Exercises have been proposed as adjuvants for the treatment of Parkinson's disease (PD); however, responses to exercise interventions have shown inconsistent results. We investigated the clinical factors associated with improvements in motor deficits after exercise.

A total of 85 patients with PD were enrolled from five tertiary hospitals and classified into four exercise groups: home exercise, strength training, Tai Chi, and yoga groups. Clinical measurements of the motor and nonmotor features of patients with PD were performed at baseline and 12 weeks after the exercise intervention. We employed principal component analysis (PCA) to reduce variables into ten factors and then examined associations of baseline characteristics with percentage improvement in the Movement Disorder Society sponsored Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS III) score via a Bayesian regression model.

In the multivariate Bayesian regression model including ten PCA-derived factors, the percentage improvement in the MDS-UPDRS III score was associated with factors including prominent motor deficits (posterior interval [mean±standard deviation]: 2.5±1.5) and nonmotor symptoms such as depression, anxiety, and subjective memory impairment (3.3±1.7). Another factor related to functional impairments in gait and postural control was associated with less improvement after the exercise intervention (-3.9±1.7). According to the subgroup analyses, motor features were associated with improvements in the home exercise and strength training groups, whereas mood disturbance, fatigue, and subjective cognitive impairment were related to changes in the home exercise and Tai Chi groups.

Our results suggest that the individual phenotypes of patients with PD may be associated with clinical improvement following exercise.