The association between cigarette smoking and radiographic progression in Psoriatic Arthritis

Objective

The association between smoking and radiographic damage has been established in axial spondyloarthritis and rheumatoid arthritis, but not in psoriatic disease. We aimed to investigate this relationship in psoriatic arthritis (PsA).

Methods

We included patients with PsA from our observational cohort. Smoking status was assessed at each clinic visit and categorized as non-smoker, past smoker, or current smoker. We used linear mixed models to identify factors associated with the overall change in damage, as measured by the modified Steinbrocker score.

Results

Of 1736 patients included in the study, 952 (54.9 %) were males; the mean (standard deviation) age at baseline was 44.9 (13.3) years. 906 (52.2 %) patients were non-smokers, 211 (12.2 %) were past smokers, and 311 (17.9 %) were current smokers; 308 (17.7 %) patients had missing smoking data. The median [interquartile range] modified Steinbrocker score at baseline was 2.0 [0.0, 10.0]. In the multivariable linear mixed model, a longer duration between the first and last sets of radiographs, a higher baseline modified Steinbrocker score, and the use of conventional synthetic DMARDs were significantly associated with an increase in joint damage. Cigarette smoking—both current (estimate -0.18, 95 % confidence interval [CI] -0.94 to 0.58) and past (estimate -0.67, 95 % CI -1.51 to 0.17)—showed no significant association with the change in modified Steinbrcoker score.

Conclusion

Cigarette smoking does not appear to be significantly associated with the progression of joint damage in PsA. Further studies are required to confirm our findings.