Habits of moderate-to-vigorous exercise were preferentially associated with slower decline of postural and gait stability, and work-related activity levels were primarily associated with slower deterioration of processing speed.
Similar to what has been previously observed, new longitudinal data from the Parkinson’s Progression Markers Initiative (PPMI) study (NCT01176565) suggests that although more moderate-to-vigorous exercise levels did not impact subsequent clinical progression in patients with Parkinson disease (PD), maintenance of regular physical activity was significantly associated with slower disease deterioration.1
A total of 237 patients with a diagnosis of early-stage PD were analyzed observationally on the effects of regular physical activity and exercise habits for a follow-up at 6 years. Baseline was defined as the point at which results of the Physical Activity Scale for the Elderly (PASE) questionnaire, a validated 12-item self-report assessment, were collected.
Led by Kazuto Tsukita, MD, Department of Neurology, Kyoto University, the study used a multivariate linear mixed-effects models to analyze the difference of effects from regular physical activity vs moderate-to-vigorous exercise. OFF state was defined using the Movement Disorders Society–Unified Parkinson’s Disease Rating (MDS-UPDRS) part 3 score, while evaluations of other specific motor functions were calculated using the Postural Instability/Gait Disturbance (PIGD) and tremor subscores.
"Our results are exciting, because they suggest it may never be too late for someone with Parkinson's to start an exercise program to improve the course of their disease. That's because we found that to slow progression of the disease, it was more important for people with Parkinson's to maintain an exercise program than it was to be active at the beginning of the disease," Tsukita said in a s statement.2
During the follow-up period, overall regular physical activity of patients with PD gradually decreased with the PASE total score decreasing by 4.5 points per year ([95% CI, –7.3 to –1.7]; Spearman’s ρ = –.08 [95% CI, –0.14 to –0.03]; P <.01), while no significant change was observed longitudinally in healthy controls (HCs; Spearman’s ρ = 0.04 [95% CI, –0.03 to –0.11]; P = .26). Moderate-to-vigorous exercise levels showed a decreasing trend in both patients with PD and HCs but did not reach statistical significance (PD: Spearman’s ρ = –0.04 [95% CI, –0.09 to 0.02]; P = .17; HCs: Spearman’s ρ = –0.04 [95% CI, –0.11 to –0.04]; P = .34).
In the following analysis which focused solely on average physical activity levels, data showed that maintaining these levels had a significant interaction effect on the PIGD subscore (ßinteraction = –0.10 [95% CI, –0.14 to –0.06]), MSE-ADL score (ßinteraction = 0.08 [95% CI, 0.04-0.12]), and Symbol Digit Modalities Test (ßinteraction = 0.05 [95% CI, 0.03-0.08]).
"We believe that our finding has the potential of changing the attitude of physicians regarding exercise counseling in patients with PD," the study authors wrote.
"Furthermore, the present study could serve as a guide for future randomized controlled trials with greater emphasis on sustained exercise in patients with PD."
Each type of activity led to different impact across the clinical parameters observed. Specifically, those who maintained moderate-to-vigorous levels of exercise showed preferential interaction on the increase in the PIGD subscore over time (ßinteraction = –0.09 [95% CI, 0.13 to –0.05]; P <.01) and had greater interaction effects of household-, work, and overall leisure-related activities. From there, work-related activity levels were shown to have an interaction effect primarily on the progression of processing speed decline (ßinteraction = 0.07 [95% CI, 0.04-0.09; P <.01). Notably, the largest interaction effect of housework-related activities was seen on the deterioration of ADL (ßinteraction = 0.09 [95% CI, 0.05-0.12]; P <.01).
There were several different strengths of the study, the authors noted, which contributed to the success of the results. First, this was the longest follow-up period that included objective evaluations of motor and cognitive function. Additionally, the robustness of the findings were confirmed by computing bootstrap 95% CIs and conducting sensitivity analyses. Lastly, using propensity score, the validity of the results remained true after comprehensive adjustment for all other baseline clinical parameters.
The benefits of physical activity and exercise have been well-documented in patients with PD. Most notably, 2021 research by Wook-Kim et al that featured more than 10,000 individuals with the disease showed an inverse association between physical activity and all-cause mortality, as well as an inverse dose-response association between the total PA amount and morality.3