Exercise Associated with Slower Declines for Patients with Parkinson’s Disease
by Lynn Hetzler
Just a little bit of exercise can affect the progression of Parkinson’s disease, according to a new study published in the Journal of Parkinson’s Disease.
Researchers at Northwestern University determined that people who regularly exercised had significantly slower declines in mobility and HRQL over a two-year period. They also found that people with advanced PD have the greatest health-related quality of life benefit from 30-minute increases in exercise each week.
About Parkinson’s Disease
Parkinson’s disease (PD) is a progressive disorder of the nervous system that affects movement and frequently results in mobility impairments. This brain disorder leads to shaking, stiffness, and difficulty with coordination, balance, and walking. Symptoms typically begin gradually and worsen over time to cause difficulty walking, talking, or completing other simple tasks. Patients with advancing Parkinson’s disease experience non-motor symptoms, such as mental and behavioral changes, memory difficulties, depression, sleep problems, and fatigue. The symptoms of PD can decrease health-related quality of life (HRQL) and increase the risk for death.
Parkinson’s disease progresses through five stages, with the first stage presenting minimal or no functional impairment aside from mild tremor, rigidity, slowness and poor condition of the arms or legs, particularly on one side of the body. Stage II may begin months or years later, as signs and symptoms develop on the other side of the body. Signs and symptoms may include bilateral loss of facial expression, decreased blinking, speech abnormalities and muscle stiffness that makes the patient appear awkward. Patients suffer loss of balance at stage III and marked incapacitation at stage IV, although patients with stage IV PD can still walk and stand unassisted. At stage V, patients are confined to bed or a wheelchair unless aided.
PD affects about a half million people in the United States, according to the National Institutes of Health (NIH), and doctors diagnose about 60,000 Americans with the condition each year. The average onset of PD is 60 years, and the risk of developing Parkinson’s disease increases with age.
Previous research shows exercise can improve symptom management and slow the progression of the disease.
The researchers used data from National Parkinson Foundation Quality Improvement Initiative (NPF-QII), which included information gathered by clinicians during participant visits. NPF-QII is an international prospective clinical study of care and outcomes, recording information from 21 sites in North America, the Netherlands, and Israel.
NPF-QII gleaned information from more than 3400 participants during clinical visits over the two-year course of the study. Information included demographics, duration of Parkinson’s disease, brief cognitive assessments and Hoehn and Yahr stage (HY), a commonly used system to describe the progression of Parkinson’s symptoms. NPF-QII also collected data on the pharmacologic and non-pharmacologic approaches to managing symptoms of the disease.
At each visit, clinicians measure the self-reported number of hours of exercise per week. Clinicians also used the Parkinson Disease Questionnaire (PDQ-39) to measure patient-reported health-related quality of life issues specific to Parkinson’s disease. The Timed Up and Go (TUG) test helps clinicians assess functional mobility. In the TUG test, researchers measure the amount of time it takes for participants to rise from a chair, walk a pre-determined distance, turn around, and then return to the original seated position.
The researchers assigned participants into two groups: those who reported 2.5 or more hours of exercise each week and those who did not exercise 2.5 hours weekly. The scientists then quantified mobility and changes in HRQL with 30-minute increases in exercises, across Parkinson’s disease severity, and using mixed regression models.
They found that, after two years, those who had already exercised consistently and those who started to exercise after the first clinician visit had smaller declines in mobility and health-related quality of life than did those who did not exercise. Participants in the non-exercisers worsened by 0.47 seconds on the TUG test and declined by 1.37 points on the PDQ-39 each year.
The results also suggest an association between increasing exercise by a half hour each week and slower declines in mobility (–0.04 sec) and HRQL (–0.16 points). The benefit of exercise on health-related quality of life was greater for those with advanced Parkinson’s disease (–0.41 points) than for those with mild PD (–0.14 points).
The study shows that starting regular exercise and continuing with consistent exercise are associated with small, but significant positive effects on mobility and health-related quality of life changes over two years. There is a greater association of exercise HRQL benefits for those with advanced PD, and this evidence supports the improvement and facilitation of exercise for individuals with advanced Parkinson’s disease.
“We found that people with Parkinson’s disease who maintained exercise 150 minutes per week had a smaller decline in quality of life and mobility over two years compared to people who did not exercise or exercised less,” said lead investigator Miriam R. Rafferty, Ph.D., of Northwestern University and Rehabilitation Institute of Chicago. “The smaller decline was significant for people who started the study as regular exercisers, as well as for people who started to exercise 150 minutes per week after their first study-related visit.”
While the study did not determine the best type of exercise to slow the progression of PD, the results suggest that engaging in at least 150 minutes of any type of exercise each week is better than not exercising at all.
“People with PD should feel empowered to find the type of exercise they enjoy, even those with more advanced symptoms,” said Dr. Rafferty.
The results of this study underscore the importance of increasing accessibility to exercise and physical activity for people with more severe PD disability. Those with more advanced Parkinson’s disease may have poor access to regular exercise, as mobility impairments limit independent participation in existing group and community exercise programs.
“The most important part of the study,” according to Dr. Rafferty, “is that it suggests that people who are not currently achieving recommended levels of exercise could start to exercise today to lessen the declines in quality of life and mobility that can occur with this progressive disease.”