People who suffer symptoms of fatigue related to their multiple sclerosis (MS) may be able to find relief by taking aspirin, according to doctors at the Mayo Clinic in Rochester, Minnesota.1
But in an accompanying editorial, two experts write that they were not convinced of the results.
Of all the symptoms of MS, fatigue is considered the most common. It is also linked with a reduced quality of life. In nearly two-thirds of patients, fatigue has been described as the worst symptom.2
Other Uses for Aspirin?
The study, headed by Dean Wingerchuk, MD, a Mayo Clinic neurologist, evaluated the effects of aspirin—what doctors call acetylsalicylic acid (uh-SEE-till-sal-uh-SILL-ik)—in a small number of patients who had fatigue related to MS. The investigators wrote that some MS patients who take aspirin for other reasons have reported feeling less fatigued, leading to studies like this to test its effectiveness.
This study was a follow-up to an earlier, smaller trial, Wingerchuk told Priority Healthcare. The previous analysis "was an open-label evaluation of 975 to 1950 mg [of] acetylsalicylic acid for MS fatigue," he explained. Seven of eight patients responded with the average dose being 1300 mg per day, which we then used in the controlled pilot [study]."
Aspirin Tested Against Placebo
For the latest analysis, Wingerchuk and his colleagues assigned the patients at random to one of two groups; the first group received 1300 mg of aspirin per day and the second group was given a placebo on the same schedule. A placebo is a non-therapeutic intervention designed to mimic the active medication being tested typically given to patients in clinical trials as a comparison.
One of the measures of treatment effectiveness was the Modified Fatigue Impact Scale, or MFIS. This is a measure of fatigue derived from interviews with people who have the disease about how it influences their lives. Physical, cognitive, and psychosocial functioning are evaluated collectively as part of this measure.3
Treatment continued for 6 weeks, then a 2-week washout period began, in which no therapy was given. Following that, patients crossed over to the alternative intervention. The entire study ran 14 weeks.
When Wingerchuk and his associates analyzed the data later, they found that the average score on the MFIS, overall, was significantly lower in patients given aspirin therapy versus those given placebo. The investigators also noted that there was a trend toward aspirin benefit on a 10-point visual analog scale.
So far, the source of aspirin's benefit for people with MS-associated fatigue isn't known.
Wingerchuk's group next plans a much larger controlled clinical trial to confirm these findings. The results, he pointed out, were similar to those achieved by a drug currently under investigation as a potential therapy for MS fatigue. "The proportion of patients who benefited in the pilot [study] was about the same as for amantadine [Symmetrel] (approx. 40%)," he said.
Experts: Study Wasn't 'Robust'
In an editorial about the study,4 Steven Schwid, MD, of the University of Rochester, New York, and T. Jock Murray, MD, of Dalhousie University in Halifax, Nova Scotia, claimed the study was weak. For instance, one measure of fatigue in the research was patients' own reports of the severity of their fatigue. "It is not clear that patients adequately distinguish effects of fatigue from motor impairment, cognitive impairment, and other symptoms commonly caused by MS," the experts wrote.
They added that fatigue must be "distinguished from other MS symptoms", and until that is accomplished, "we will not make substantial progress in treating this disabling symptom."
However, they didn't completely write aspirin off. "The reasonably favorable safety profile and minimal expense of aspirin warrant additional studies," the two experts concluded.
1. Wingerchuk DM, Benarroch EE, O'Brien PC et al. A randomized controlled crossover trial of aspirin for fatigue in multiple sclerosis. Neurology 2005 Apr 12;64(7):1267-9.
2. Zifko UA. Management of fatigue in patients with multiple sclerosis. Drugs 2004;64(12):1295-304.
3. National Multiple Sclerosis Society. Measures for Use in Clinical Studies of MS. Available at: http://www.nationalmssociety.org/%5CMUCS_fatigue.asp. Accessed April 29, 2005.
4. Schwid SR, Murray TJ. Treating fatigue in patients with MS: one step forward, one step back. Neurology 2005 Apr 12;64(7):1111-2.
John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include coverage of health news for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.
