Low to Moderate Alcohol Consumption Associated with Less Disability in Patients with MS, Study Finds

Alcohol consumption has been known to dampen both B-cell and T-cell immunity and reduce interleukin-21 production, all of which are associated with multiple sclerosis (MS) disease severity and progression. Previous studies have also observed a decreased risk of autoimmune disorders, including MS, in people who consume alcohol. However, it is not known whether patients may reduce their alcohol consumption as their disease progresses. Thus, the lowered risk could be due to reverse causation.

In a study published in the September 2024 issue of Neurology: Neuroimmunology and Neuroinflammation, Jing Wu, Ph.D., and his colleagues from the Institute of Environmental Medicine and the Department of Clinical Neuroscience at the Karolinska Institutet in Stockholm sought to investigate the effect of alcohol consumption on MS disease progression and evaluate the potential for reverse causation.

The researchers used data from two Swedish population-based studies and followed 9,051 patients with MS for 15 years using the Swedish MS registry. Based on answers from a lifestyle habit questionnaire, the participants were categorized into the following categories regarding alcohol consumption at the time of diagnosis: 1) nondrinking, 2) low alcohol consumption, 3) moderate alcohol consumption, and 4) high alcohol consumption.

Low alcohol consumption was defined as less than 50 grams per week for women and 100 grams for men. Moderate consumption was 50 to 108 grams per week for women and 100 to 168 grams for men. High alcohol consumption was considered more than 108 grams per week for women and 168 grams for men. In the U.S., a standard drink contains 14 grams of alcohol.

Of the 9,051 patients followed, 44% were nondrinkers, 38% were low alcohol consumers, 12% were moderate consumers, and 6% were high consumers at the time of diagnosis.

The primary endpoint was confirmed disability worsening as defined by an increase of at least 1 point from baseline in the Expanded Disability Status Scale (EDSS), sustained between two follow-up visits no less than six months apart. If the baseline EDSS score was 0, a 1.5-point increase was used. If the baseline EDSS score was greater than 5.5, a 0.5-point increase was used.

The results showed that people who were low or moderate alcohol consumers had a decreased risk of EDSS-related negative outcomes and physical worsening compared with nondrinkers. However, this effect was only seen in patients with relapsing-remitting MS. High alcohol consumption did not have a significant effect on disease outcomes. Additionally, the inverse relationship between low or moderate alcohol consumption and disease progression was stronger when the analysis isolated participants who did not change their alcohol consumption habits between the time of diagnosis and the end of the follow-up period, negating a potential reverse causation effect.

Wu and his colleagues note that, given the varied effects of alcohol on each person, the results from this study should be evaluated and implemented on an individual basis.

They wrote, “Communicating and implementing data on the potential beneficial effects of alcohol in MS is challenging, given the well-documented adverse effects of alcohol consumption on human health.”

“However, we believe that this knowledge should be disseminated because further research into underlying mechanisms may offer insights into how to mitigate disease progression through the development of alternative treatments or dietary interventions that do not involve alcohol,” the authors added.