Feb. 23, 2009
UI/VA team studies effect of exercise on cognition in Parkinson's disease
Parkinson's disease is primarily known for its physical effects: tremors and problems with movement. However, the disease also impairs cognition, including attention, memory and executive functions such as decision-making, in many patients and can seriously diminish their ability to live independently.
Researchers at the Iowa City Veterans Affairs Medical Center and the University of Iowa are investigating whether a very simple intervention -- aerobic exercise -- can produce physiological and neurological changes that might lead to improved cognition in patients with Parkinson's disease.
"Our studies have shown that cognitive dysfunction, even at an early stage of the disease without dementia, is a very important problem that impairs independence and driving abilities in patients with Parkinson's disease," said Ergun Uc, M.D., staff physician at the Iowa City VA Medical Center and UI associate professor of neurology. "However, we do not know how to improve cognition in Parkinson's disease."
Moderate increases in cardiovascular fitness have been shown to improve cognition in older people who do not have Parkinson's disease. These studies suggest that the improvement may be caused by changes in brain chemicals and circulation that are thought to improve the adaptation of the brain to aging.
Uc and his colleagues are pursuing the idea that aerobic exercise may produce similar benefits for people with Parkinson's disease.
Their preliminary research suggests that higher cardiovascular fitness is associated with better performance on some tests of cognitive function, as well as mobility, in Parkinson's disease. Studies in the literature also suggest that patients with mild to moderate Parkinson's disease can tolerate aerobic exercise programs and show improvements in cardiovascular fitness and motor function.
"Our next step is to find out if aerobic exercise in the form of brisk walking in mild to moderate Parkinson's produces sufficient increases in cardiovascular fitness and neurobiological effects to merit moving to a Phase III definitive clinical trial to test its efficacy on improving cognitive performance," Uc said.
To investigate the neurobiological effects of exercise, the team plans to use magnetic resonance imaging (MRI) and blood tests. The MRI will help determine if aerobic exercise produces changes in brain structure and function that could support better cognition. The blood tests will measure the effect of exercise on chemicals that support brain function.
The work is funded by a grant from the Department of Veterans Affairs and supported by the UI Institute for Clinical and Translational Science.
In addition to Uc, who is the study's principal investigator, the multidisciplinary research team includes UI researchers, Warren Darling, Ph.D., associate professor of integrative physiology; Kevin Doerschug, M.D., clinical associate professor of internal medicine; Jeffrey Dawson, Sc.D., associate professor of biostatistics; Steven Anderson, Ph.D., associate professor of neurology; Teri Thomsen, M.D., clinical assistant professor of neurology; and David Rudrauf, Ph.D., assistant professor of neurology.
STORY SOURCE: University of Iowa Health Care Media Relations, 5135 Westlawn, Iowa City, Iowa 52242-1178