To investigate the association between frequency of alcohol consumption and the risk and severity of RA.
Frequency of alcohol consumption was recorded by patients and controls in a self-completed questionnaire. Odds ratios (ORs) for RA risk were calculated according to alcohol consumption, adjusted for age, gender and smoking status. Median values of all RA severity measures were then calculated according to the frequency of alcohol consumption, and the non-parametric trend test was used to assess association. A negative binomial regression model was used to adjust for potential confounding.
Eight hundred and seventy-three patients with erosive RA, and 1004 healthy controls were included in the study. Risk of RA decreased according to frequency of alcohol consumption, such that non-drinkers had an OR for RA of 4.17 (3.01-5.77) compared with subjects consuming alcohol on >10 days per month (P for trend <0.0001). All measures of RA severity including CRP, 28-joint DAS, pain visual analogue scale, modified HAQ (mHAQ) and modified Larsen score were inversely associated with increasing frequency of alcohol consumption (P for trend, each <0.0001). After adjustment for potential confounding in a multivariate regression model, frequency of alcohol consumption remained significantly and inversely associated with X-ray damage and mHAQ.
Although there are some limitations to this study, our data suggest that alcohol consumption has an inverse and dose-related association with both risk and severity of RA.