Yoga, Exercise Improve Fatigue Associated With Multiple Sclerosis
June 11, 2004
Yoga and exercise are about equally effective in improving symptoms of fatigue but not of cognitive dysfunction in patients with multiple sclerosis (MS), according to the results of a randomized trial published in the June 8 issue of Neurology.
"Besides quality of life, fatigue, and mood, there are a number of cognitive changes often associated in MS that may be impacted by yoga or physical activity," write Barry S. Oken, MD, from Oregon Health & Science University in Portland, and colleagues. "Despite the widespread advocacy and use of yoga in MS, there have been no controlled clinical trials."
The investigators randomized 69 subjects with clinically definite MS and Expanded Disability Status Score not greater than 6.0 to one of three groups: weekly Iyengar yoga class along with home practice, weekly exercise class using a stationary bicycle along with home exercise, or a waiting-list control group.
Of the 69 subjects, 12 subjects did not complete the six-month study. There were no adverse events from either active intervention. On a battery of cognitive measures focused on attention and on physiologic measures of alertness, neither active intervention was associated with significant improvement on either of the primary outcome measures of attention or alertness.
Compared with the control group, both active interventions produced improvement in secondary measures of fatigue, including the Energy and Fatigue (Vitality) score on the Short Form (SF)-36 health-related quality of life, and general fatigue on the Multi-Dimensional Fatigue Inventory (MFI). There were no clear changes in mood related to yoga or exercise, based on the Profile of Mood States and State-Trait Anxiety Inventory.
Potential study limitations include possibly random results from multiple comparisons, lack of power for medium effect sizes, preponderance of female subjects, and lack of generalizability to a typical community yoga or exercise class.
"While there are claims that yoga may affect the underlying disease process in MS, this six-month intervention study was not designed to determine whether there would be any impact on the underlying disease," the authors write. "The absence of statistically significant effects on the mood and cognitive measures needs to be interpreted cautiously and is still open to investigation. There is a possibility that mood improvements contributed to these improvements in quality of life and fatigue."