Current cigarette use in rheumatoid arthritis patients: associated factors and a limited mediating role of depression

Some newly published studies revealed that current smoking was associated with accelerated disease progression in diagnosed rheumatoid arthritis (RA) patients. The major aims of this study were to analyze the associated factors of current smoking in RA patients and explore the mediating role of depression in the associations between identified factors and smoking. RA patients were selected from NHANES databases 2005–2012. Current smoking was determined by race-specific serum cotinine levels. Depression was measured by the Depression Screener questionnaire. Totally, 848 RA patients were identified and included into final analysis. Logistic regression model founds that age, race, and socioeconomic status (SES) were associated with current smoking in RA patients: the odds ratios (ORs) of smoking were 0.29 (95 % CI 0.17, 0.49) and 0.39 (95 % CI 0.24, 0.62) in patients over 60 years old and of higher SES, respectively; non-Hispanic white patients with a pre-RA smoking history had an OR of 3.48 (95 % CI 1.35, 5.18) when compared with patients of other race with no pre-RA smoking history. Structural equation model identified a weak mediating role of depression, only accounted for 5 % of the total SES–smoking association. In this sample of diagnosed RA patients, age, SES, ethnicity, but not depression, were significantly associated with current smoking.