The association between objectively measured physical activity, depression, cognition, and health-related quality of life in Parkinson's disease

Lower levels of physical activity are associated with lower Health-Related Quality of Life (HRQoL) in Parkinson's disease (PD). We evaluated the influence of quantitative physical activity parameters among other (disease-related) features representing other domains of the WHO International model for classification of Function, Disability, and Health (ICF) on HRQoL in PD. Home-based movement data (DynaPort MiniMod®) was collected in 47 PD patients. Nine stepwise regression models were calculated, with consecutive outcome variables: Parkinson's Disease Questionnaire (PDQ) Summary Index (SI), PDQ-Mobility, PDQ-Activities of Daily Living (ADL). Demographic variables, disease-specific features, and quantitative physical activity parameters, were included as predicting variables in all analyses. The following three physical activity parameters were alternately included for both sedentary and active episodes: ‘percentage’ of 24 h spent within these episodes, ‘number of bouts’, and ‘mean bout lengths’ (MBL). Depression and ‘Total Energy Expenditure’ were the main predictors of overall HRQoL (PDQ-SI), independent of the permutation of activity parameters. The same parameters predicted the PDQ-Mobility score. However, this result was altered when ‘MBL’ parameters were included into the model, ‘MBL’ of sedentary episodes additionally predicted HRQoL-Mobility. The PDQ-ADL score was associated with demographic, motor, and non-motor variables including cognitive status. After exclusion of demented PD patients, older age and cognitive impairment no longer constrained HRQoL-ADL. For the first time, we showed the influence of objective, home-based measured physical activity among depression and cognition on HRQoL in PD. This suggests that a multifactorial treatment approach would be most successful to increase HRQoL in PD. •Depression and physical activity independently predict Health-Related Quality of Life (HRQoL) in Parkinson's Disease (PD).•PD patients with higher levels of physical activity, better cognitive function, less severe signs of depression have higher HRQoL, even after systematic correction for other parameters.•Total energy expenditure is the major physical activity predictor for the HRQoL in PD.•A wide variety of factors influence the HRQoL activities of daily living domain in PD.•Long periods of sedentary episodes predict lower HRQoL in the mobility and activities of daily living domain in PD.