Dose-Dependent Association Identified Between Parkinson Disease and Physical Activity
Performing physical activity after receiving a diagnosis of Parkinson disease was associated with a decreased mortality rate, even in individuals with PD who were physically inactive before diagnosis.
Yong Wook-Kim, MD, PhD
An analysis featuring more than 10,000 individuals with Parkinson disease (PD) found an inverse association between physical activity (PA) and all-cause mortality as well as an inverse dose-response association between the total PA amount and mortality.
In this nationwide population-based cohort study, 10,699 individuals with PD who were at least 40 years old were asked to self-report on PA levels using structured questionnaires. Patients were included from January 1, 2010, and December 31, 2013, and were followed up until December 31, 2017. Senior author Yong Wook-Kim, MD, PhD, Department of Rehabilitation Medicine, Yonsei University College of Medicine, Seoul, and colleagues calculated the total metabolic equivalent of task (MET) minutes per week to quantify the total PA amount. The MET ratings of 3, 5, and 8 were assigned for light-intensity, moderate-intensity, and vigorous-intensity activities.
Among the total cohort followed up for 8 years, there were 1823 deaths (mortality rate, 17%). For individuals who were physically active, investigators observed a significantly reduced morality risk. After adjusting for confounding variables, Cox proportional hazard regression models for morality showed HRs of 0.80 (95% CI, 0.69-0.93) for vigorous-intensity PA, 0.66 (95% CI, 0.55-0.78) for moderate-intensity PA, and 0.81 (95% CI, 0.73-0.90) for light-intensity PA.
"Activity modification to increase and maintain PA would be beneficial for PD management, and future prospective randomized clinical trials to elucidate causal associations between PA and mortality in PA are warranted," the study authors wrote.
READ MORE: A New Approach to Protein Misfolding in Parkinson Disease
From those in the first MET quartile (<90 MET-minutes per week) to the fourth quartile (≥820 MET-minutes per week), multivariate Cox proportional hazards regression analysis identified a progressively decreasing risk of mortality (HR, 0.61 [95% CI, 0.53-0.70]; P <.001). Furthermore, log-rank test revealed a significant inverse association between mortality rate and total amount of PA in individuals with PD (P <.001).
Physically active participants who continued their PA after diagnosis of PD showed the greatest reduction in mortality rate for all PA intensities (vigorous: HR, 0.66 [95% CI, 0.50-0.88]; moderate: HR, 0.49 [95% CI, 0.32-0.75]; light: HR, 0.76 [95% CI, 0.66-0.89]). Compared with those who remained physically active, individuals who started PA after receiving their diagnosis showed a lower mortality rate (vigorous: HR, 0.82 [95% CI, 0.70-0.97]; moderate: HR, 0.69 [95% CI, 0.57-0.83]; light: HR, 0.86 [95% CI, 0.78-0.98]).
A subgroup that looked at variables such as age, sex, alcohol consumption, smoking, and body mass index (BMI) on associations between PA and mortality were all nonsignificant, and the inverse association between PA and mortality remained consistent. Increased mortality was associated with age (HR, 1.07 [95% CI, 1.06-1.07]; P <.001), disability registration (HR, 1.92 [95% CI, 1.66-2.23]; P <.001), and Charlson Comorbidity Index (HR, 1.13 [95% CI, 1.11-1.16]; P <.001), whereas female sex (HR, 0.53 [95% CI, 0.48-0.58]; P <.001) and BMI (HR, 0.94 [95% CI, 0.92-0.95]; P <.001) were associated with reduced mortality.
There were several limitations, including the fact that study only included those who underwent health checkups within 2 years before and after diagnosis were used, making it possible that only individuals with PD who were relatively healthy or had health-seeking behaviors were enrolled in the analysis. Additionally, there could be recall bias, as all collected PA information was from self-reported questionnaires. Lastly, the analysis did not include caffeine consumption and dietary habits, nor did it include antiparkinsonian medication use.
