Drinking tied to RA disease activity

Alcohol consumption appears to influence outcomes in patients with rheumatoid arthritis (RA), with a recent study showing that low to moderate drinkers have a lower disease activity and higher health-related quality of life than abstainers.

At baseline, abstainers already had higher disease activity and estimated their pain as more severe compared with drinkers. This difference persisted at the 1-year follow-up, where abstainers reported higher swollen and tender joint counts, experienced more pain and fatigue, and had lower global health and health-related quality of life. [Arthritis Rheumatol 2023;doi:10.1002/art.42442]

“There were no differences in measures of disease activity and disability at baseline between drinkers who continued drinking alcohol and those who later discontinued, whereas those who discontinued alcohol consumption had higher disease activity and disability at 1-year follow-up,” according to the investigators.

The findings, however, must be interpreted with caution, given the harmful effects of alcohol consumption on human health, they added.

Immunomodulatory properties

“[T]hat alcohol consumption is related to RA disease activity and health-related quality of life independently of anticitrullinated protein antibody (ACPA) status, rheumatoid factor (RF) status, human leukocyte antigen (HLA)-DRB1 shared epitope status, smoking, and obesity,” may be explained by alcohol’s dose-dependent immunomodulatory properties, the investigators pointed out.

The said immunomodulatory properties have been shown to reduce innate inflammatory responses in humans, with the levels of inflammatory markers being lower in individuals with moderate alcohol intake but elevated in those with heavy intake as compared with nondrinkers. [Br J Nutr 2007;98:111-115; Lancet 2001;357:763-767; Nat Commun 2020;11:1998]

“In experimental studies, moderate alcohol has also been shown to reduce the incidence of collagen-induced arthritis… An additional possibility is … that alcohol may induce generation of gut-derived anti-inflammatory fatty acids,” the investigators noted. [Nat Commun 2020;11:1998; Gut Microbes 2021;13:1916278]

Weighing the pros and cons

The current study used data from the population-based case-control study EIRA (Epidemiological Investigation of Rheumatoid Arthritis) and included 1,228 patients with newly diagnosed RA. The mean alcohol consumption among drinkers at baseline bordered between low and moderate (52 gram/week among women and 112 gram/week among men). Alcohol consumption at baseline (gram/week) correlated with ACPA negativity (p=0.002), RF status (p=0.003), and smoking (p<0.0001).

At the 1-year follow-up, the frequency of alcohol consumption was once per month for 23 percent of the patients, 2–3 times per month for 43 percent, 2–3 times per week for 29 percent, and 4 times per week or more for 5 percent.

Compared with patients who consumed alcohol, nondrinkers had greater odds of having a health-related quality of life below the median (physical aspect: odds ratio [OR] 2.6, 95 percent confidence interval [CI], 1.6–4.2; mental aspect: OR, 2.1, 95 percent CI, 1.3–3.3), pain above the median (OR, 1.6, 95 percent CI, 1.0–2.5), fatigue above the median (OR, 1.5, 95 percent CI, 1.0–2.3), and global health below the median (OR, 1.7, 95 percent CI, 1.1–2.6).

Issues regarding the potential mechanisms underlying the benefit of alcohol consumption on RA outcomes and what advice physicians should give to provide to patients and caregivers have yet to be addressed, the investigators acknowledged.

“How to directly communicate and implement the previous and current data on favourable effects of alcohol consumption in RA is more complex,” they said. “We believe that the knowledge must be communicated to the scientific community but implementation of this knowledge in the clinics be very individualized, taking both potential advantages and disadvantages of alcohol consumption into account.”