Patients with mild to moderate Parkinson’s disease who walked regularly for 6 months at the federally recommended level and duration each week improved in several disease-related and quality of life factors, according to the results of a study published July 2 in Neurology.
"Our results suggest that patients with mild to moderate PD can safely exercise per the guidelines for the general adult population and experience benefits," Dr. Ergun Y. Uc of the department of neurology at the University of Iowa, Iowa City, and his associates wrote in their report. The Department of Health & Human Services’ guidelines for physical activity are 150 minutes per week of moderate-intensity aerobic activity for healthy adults aged 18-65 years.
The investigators observed 60 patients with Parkinson’s disease (mean age at baseline, 65 years) who were required to exercise three times per week and wear electronic heart rate and walking speed monitors. During the first 2 years of the study, 43 patients had been randomly assigned to either continuous/moderate intensity training or interval training that alternated between low and vigorous intensity, but the remaining 17 patients were assigned to continuous training because preliminary analyses indicated a higher rate of musculoskeletal adverse events in those assigned to interval training. Their exercise duration increased from 15 minutes to 45 minutes over the first 6 weeks. They had a mean walking speed of 2.9 miles/hour.
Significant improvement was observed in aerobic fitness, with a mean increase of 1.56 mL/min per kilogram in maximum oxygen uptake. "Maximal effort" was defined as meeting two of three criteria: a plateau in oxygen uptake between two or more workloads, a respiratory exchange ratio of at least 1.10, and a heart rate 85% or more of age-predicted maximal heart rate (Neurology 2014;83:1-13).
The participants also experienced a mean improvement in cognition (–2.41%), based on the change in percent increase score on the Eriksen flanker task.
Parkinsonism significantly improved by a mean of –3.37 points on the Unified Parkinson’s Disease Rating Scale, and quality of life rose significantly based on a decline of 1.62 points in mean score on the Parkinson’s Disease Quality of Life Scale.
Additionally, the patients’ mean improvement of 2.8 points in the motor UPDRS score "appears to be meaningful because it exceeded the reported mean minimal clinically important difference of 2.5 (2.3-2.7) points."
All of the mean changes in the factors that the investigators measured were adjusted simultaneously for different training methods and settings, calendar year, and change in levodopa equivalent.
The investigators acknowledged that the lack of a control group is a limitation of the study and that the results cannot prove efficacy, but provide guidance for a future phase III study.
The study was funded primarily by the Department of Veterans Affairs, Rehabilitation R&D Branch Merit Review Award, with additional support from other sources.