Non-motor symptoms are associated with change in physical activity over 18 months in incident Parkinson’s disease (PD)

[Poster] Objective: To examine if non-motor symptoms can predict change in levels of physical activity (PA) within a cohort of incident Parkinson's disease (PD) over 18 months. Background: PA is important to maintain a healthy lifestyle. Beneficial effects of PA have been reported for people with PD, and there is evidence to suggest it may be neuroprotective. Most people with PD do not achieve recommended levels [1] although the reasons for this are still largely unclear. It is therefore important to understand the potential drivers behind PA. Methods: For this preliminary analysis, 35 people with PD [mean (SD) age 67.4 (10.4) years; 14 females; UPDRS III 23(10)] were recruited through an ongoing longitudinal study (ICICLE-PD). PA was measured for 7 days at baseline and 18 months, using a uniaxial accelerometer (ActivPALTM). PA outcomes included: 1) pattern of accumulation of activity (α); 2) number of steps accumulated in longer bouts (>100 steps) and total steps; and 3) variability of stepping bout duration. A range of cognitive, motor, affective and quality of life outcomes were measured, including quality of life (PDQ 39), the Geriatric Depression Scale (GDS), MDS-UPDRS III, total fatigue (MFI), cognitive function and attention. Partial correlations were used to explore the relationship between baseline cognitive, motor and affective factors, and change in PA over 18 months. Multiple regression analysis identified independent predictors of change in PA over 18 months. Results: At baseline, cognitive and motor function was not significantly associated with changes in PA. Partial correlations showed GDS and total fatigue to be significantly correlated with total number of steps and the number of steps accumulated in longer bouts. Multiple regression analysis showed that a more severe GDS score was an independent predictor of a decrease in the number of steps accumulated in longer bouts (F (5, 34) = 2.81, r2 = .27, p<.05). Conclusions: More severe affective symptoms (GDS) are related to a reduction over 18 months in the number of steps accumulated during longer stepping bouts in incident PD. Future analysis will be performed on a larger cohort and compared with aged-matched controls. Reference: 1. Lord, S., Godfrey, A., Galna, B., Mhiripiri, D., Burn, D., and Rochester, L. (2013). Ambulatory activity in incident Parkinson's: more than meets the eye? Journal of Neurology DOI 10.1007/s00415-013-7037