Cannabis extract, physical activity, and cognitive behavioral therapy are complementary and alternative medicines (CAMs) with the strongest evidence of efficacy for multiple sclerosis (MS), according to a systematic review published in the January issue of Journal of Neurology, Neurosurgery and Psychiatry. However, there is little class I and class II evidence to support the effect of CAMs.
“We found little evidence for CAM treatments of MS, and class I evidence was almost universally lacking,” said Suzi B. Claflin, PhD, a postdoctoral research fellow at Menzies Institute for Medical Research at the University of Tasmania in Hobart, Australia, and colleagues. Some CAM treatments were evaluated in a single study, and when treatments were evaluated in more than one study, the studies “had different designs and methodologies, and in some cases, contradictory results.”
A Systematic Review
There is an in interest in CAM treatments among the MS community, possibly due to perceived and actual shortcomings of available pharmacologic treatments, said the researchers. Cross-sectional studies have found that 37% to 100% of patients with MS have used CAMs at some point in their lives, and up to 51.8% of these patients have used CAMs in the past year. Despite the common use of CAMs, there is a lack of understanding of their efficacy, the authors noted.
The World Health Organization has defined CAM as “a broad set of health care practices that are not part of [a] country’s own tradition and are not integrated into the dominant health care system.” For the present review, however, the researchers defined CAM broadly as a noninvasive therapy used in addition to or in lieu of the standard pharmacologic treatment of MS.
To provide an overview of the modern evidence for CAM use in patients with MS and to highlight future directions for research, Dr. Claflin and colleagues conducted a systematic review of full research articles published between January 1, 2001, and January 18, 2017, that were written in English, had only human participants, and tested the effect of a CAM treatment on health outcomes in patients with MS only. The researchers included in their review studies with at least 50 participants that provided class I or class II evidence of efficacy. In all, they included 38 studies and divided them into the following five CAM types: cannabis, diet, exercise, psychologic approaches, and other.
Best-Supported Evidence
Five studies found significant beneficial effects of cannabis extract for incontinence, pain, spasticity, and muscle stiffness, whereas two studies found no effect of cannabis extract on primary outcomes. A single study found a positive effect of tetrahydrocannabinol extract on incontinence, and one study found no effect for this treatment on spasticity.
Psychologic approaches such as cognitive behavioral therapy (CBT) appear to be effective in treating MS-related psychologic symptoms. Seven class II studies found that CBT significantly improved depression, fatigue, distress, and general health. In one study, there was no effect of CBT on functional impairment. In a single study, there was no effect of cognitive rehabilitation on function. In another study, mindfulness significantly improved health-related quality of life, depression, and fatigue.
Among exercise treatments, some balance and gait training techniques significantly improved fatigue, balance, walking, and endurance, while other techniques did not. Exercise generally was found to improve muscle strength and mobility-related health outcomes in several studies, and may have some effect on psychologic symptoms. In several studies, however, primary outcomes were not significantly affected. In a single study, yoga had no effect on attention and alertness. In another study, group yoga was not effective in improving MS Impact Scale scores, but some effects on secondary outcomes were observed.
Least-Supported Evidence
Among dietary treatments, biotin had a significant effect on disability progression in one study. In another single study, there was no effect of gingko biloba on cognitive function. Two studies of polyunsaturated fatty acid supplementation for disability had contradictory results: one study found that the treatment reduced relapse rate, and another study found no effect on gadolinium-enhancing lesions. In addition, three studies found no effect of vitamin D supplementation after MS onset on primary outcomes, but one of the studies found some suggestion of benefit of vitamin D as an add-on treatment.
Among other CAMs, acupressure significantly reduced fatigue in a single study. In another single study, amphetamine salts improved processing speed. Two studies found contradictory results for the efficacy of reflexology for pain. Finally, one study found a positive effect of relaxation on stress and depression, and one study found a positive effect of relaxation on pain.
“In order to improve our understanding of the effects of CAM on MS health outcomes, future work should cultivate methodological consistency by establishing standard control or comparator groups and outcome measures,” said Dr. Claflin and colleagues. “This field would also be well served by establishing outcomes of interest, which would allow for greater replication and the accrual of a depth of evidence about an outcome.”