Smoking as a risk factor for the radiological severity of rheumatoid arthritis: a study on six cohorts
Publication Date
2014
Journal Title
Ann Rheum Dis
Abstract
Background Smoking is a risk factor for the development of anti -citrullinated protein antibodies (ACPA) positive rheumatoid arthritis (RA). Whether smoking predisposes to severe joint damage progression is not known, since deleterious, protective and neutral observations have been made. Objective To determine the effect of smoking on joint damage progression. Methods Smoking status was assessed in 3158 RA patients included in six cohorts (Leiden Early Arthritis Clinic (Leiden-EAC), BARFOT, Lund, Iceland, NDB and Wichita). In total 9412 radiographs were assessed. Multivariate normal regression and linear regression analyses were performed. Data were summarised in a random effects inverse variance meta-analysis. Results When comparing radiological progression for RA patients that were never, past and current smokers, smoking was significantly associated with more severe joint damage in Leiden-EAC (p=0.042) and BARFOT (p=0.015) RA patients. No significant associations were found in the other cohorts, though a meta-analysis on the six cohorts showed significantly more severe joint damage progression in smokers (p=0.01). Since smoking predisposes to ACPA, analyses were repeated with ACPA as additional adjustment factor. Then the association was lost (meta-analysis p=0.29). Conclusions This multi-cohort study indicated that the effect of smoking on joint damage is mediated via ACPA and that smoking is not an independent risk factor for radiological progression in RA.
Volume Number
73
Issue Number
7
Pages
1384-1387
Document Type
Article
Status
Faculty
Facility
School of Medicine
Primary Department
Molecular Medicine
Additional Departments
General Internal Medicine
PMID
DOI
10.1136/annrheumdis-2013-203940