Study identifies possible reason why moderate alcohol consumption may lower lupus risk

Moderate alcohol consumption has been associated with decreased systemic lupus erythematosus risk, but the biologic basis for this association is unknown. A study investigated whether moderate alcohol consumption was associated with lower concentrations of systemic lupus erythematosus-associated chemokines/cytokines in an ongoing cohort of female nurses without systemic lupus erythematosus, and whether the association was modified by the presence of systemic lupus erythematosus-related autoantibodies.
Data was drawn from a study population of 1,117 women from the Nurses’ Health Study and Nurses’ Health Study 2 who donated a blood sample. Their average age was 56 and 46% were African American. Cumulative average and current intakes of beer, wine or liquor were assessed. 46% reported consuming 0-5 g/day of alcohol. Chemokine/cytokine concentrations (stem cell factor, B-lymphocyte stimulator, interferon-inducible protein-10, interferon-alpha, interleukin-10) and antibodies against dsDNA and extractable nuclear antigens were obtained from the blood sample. 22% were antinuclear antibody (ANA) positive – a potential marker of autoimmune disease.
The researchers found that stem cell factor levels (SCF) were 0.5% lower for every gram per day increase in cumulative average alcohol consumption. Women who consumed >5 g/day had mean stem cell factor levels 7% lower than non-drinkers. Other cytokines were not significantly associated with alcohol intake. Autoantibody status did not modify observed associations.
Karen H. Costenbader, MD, MPH, lead author and Chair of the Lupus Foundation of America’s Medical-Scientific Advisory Committee notes, “Interestingly, in these healthy women we found that cumulative moderate alcohol intake (in the range of 1/2 drink-1 drink a day, the same range that is associated with a decrease in lupus risk) was associated with a decrease in SCF production. Since SCF has been shown to be elevated in lupus and even pre-lupus, we are thinking, but don’t yet know, that reducing SCF production may be a potential mechanism by which alcohol reduces lupus risk.”
Alcohol is known to affect the immune system, and previous studies have also found moderate alcohol consumption to be associated with decreased lupus risk. However, this is the first known study to identify alcohol’s association with SCF as the possible reason for what could be a cause-and-effect relationship between moderate drinking and reduced lupus risk.
Source: Hahn J, Leatherwood C, Malspeis S, et al. Associations between daily alcohol consumption and systemic lupus erythematosus-related cytokines and chemokines among US female nurses without SLE. Lupus. 2020;29(8):976-982.