Moderate use of alcohol is associated with lower levels of C reactive protein but not with less severe joint inflammation: a cross-sectional study in early RA and healthy volunteers

OBJECTIVES: Moderate alcohol consumption is protective against rheumatoid arthritis (RA) development and associated with lower levels of systemic inflammation in RA and in the general population. We therefore hypothesised that moderate alcohol consumption is associated with less severe local inflammation in joints in RA, detected by MRI. Since asymptomatic persons can have low-grade MRI-detected inflammation, we also hypothesised that alcohol consumption is associated with the extent of MRI inflammation in asymptomatic volunteers. METHODS: 188 newly presenting patients with RA and 192 asymptomatic volunteers underwent a unilateral contrast-enhanced 1.5T MRI of metacarpophalangeal, wrist and metatarsophalangeal joints. The MRIs were scored on synovitis, bone marrow oedema and tenosynovitis; the sum of these yielded the MRI inflammation score. MRI data were evaluated in relation to current alcohol consumption, categorised as non-drinkers, consuming 1–7 drinks/week, 8–14 drinks/week and >14 drinks/week. Association between C reactive protein (CRP) level and alcohol was studied in 1070 newly presenting patients with RA. RESULTS: Alcohol consumption was not associated with the severity of MRI-detected inflammation in hand and foot joints of patients with RA (P=0.55) and asymptomatic volunteers (P=0.33). A J-shaped curve was observed in the association between alcohol consumption and CRP level, with the lowest levels in patients consuming 1–7 drinks/week (P=0.037). CONCLUSION: Despite the fact that moderate alcohol consumption has been shown protective against RA, and our data confirm a J-shaped association of alcohol consumption with CRP levels in RA, alcohol was not associated with the severity of joint inflammation. The present data suggest that the pathophysiological mechanism underlying the effect of alcohol consists of a systemic effect that might not involve the joints.