To study the association between smoking, anti-modified citrullinated (MCV) antibodies and some associated antibodies, and disease activity.

Anti-cyclic citrullinated peptide (CCP) antibodies and anti-MCV antibodies were detected by enzyme-linked immunosorbent assay (ELISA) . RF was detected by latex agglutination test. The clinical and laboratory data of 632 patients with RA were collected. We kept a record of the daily smoking quantity, smoking years of RA patients. T test, analysis of variance (ANOVA) analysis, SNK-q test and Spearman correlation analysis were used for statistical analysis.

Anti-MCV antibody level was positively related to disease activity score (DAS28), erythrocyte sedimentation rate (ESR), C reactive protein (CRP), tender joint counts (r=0.091, 0.119, 0.122, 0.124, P<0.05). Rheumatoid factor (RF) level was positively related to DAS28, ESR and CRP (r=0.182, 0.192, 0.171, P<0.05). The positive rates of anti-MCV antibodies, anti-CCP antibodies and RF were 1.631 times, 1.489 times and 1.350 times higher in smokers than those of the non-smokers respectively. Their 95%CI were (0.721, 3.690), (0.573, 3.871) and (0.781, 2.334) respectively. The CRP level of smokers [(38±64) mg/L] was higher than that of non-smokers [(30±51) mg//L, t=-2.653, P<0.05]. They were not related to disease activity. The level of antibodies and disease activity were not changed with smoking quantity. The CRP level of patients who smoked 1 to 9 pack-years[(12±25) mg/L] was lower than those who smoked 10 to 19 pack-years and more than 20 pack-years patients [(73±76) mg/L, (39±63) mg/L] (P<0.05).

Anti-MCV antibody is better than anti-CCP antibody and RF in reflecting disease activity. The CRP level of patients is corrected with smoking. No association is observed between disease activity and the quantity of smoking.

arthritis, rheumatoid; Vimentin; Smoking