Associations of Smoking and Age With Inflammatory Joint Signs Among Unaffected First‐Degree Relatives of Rheumatoid Arthritis Patients: Results From Studies of the Etiology of Rheumatoid Arthritis
Year: 2016
Type: article
Study design: Observational Study
Abstract: OBJECTIVE: To examine whether genetic, environmental, and serologic rheumatoid arthritis (RA) risk factors are associated with inflammatory joint signs in a cohort of first-degree relatives (FDRs) of RA patients. METHODS: We evaluated RA risk factors and inflammatory joint signs in a prospective cohort of FDRs without RA in the Studies of the Etiology of RA. Genetic factors included 5 HLA-DRB1 shared epitope alleles and 45 RA-associated single-nucleotide polymorphisms; loci were combined using genetic risk scores weighted by RA risk. Environmental factors (smoking, body mass index, education, and parity) and RA-related autoantibodies were assessed at baseline. Physical examination was performed at baseline and 2-year follow-up, by observers who were blinded with regard to autoantibody status, to assess inflammatory joint signs as tender or swollen joints at sites typical for RA. Logistic regression was performed to evaluate associations of genetic, environmental, and serologic factors with inflammatory joint signs. RESULTS: We analyzed 966 non-Hispanic white FDRs at baseline and 262 at 2-year follow-up after excluding those with inflammatory joint signs at baseline. The mean ± SD age was 47.2 ± 15.5 years, 71% were female, and 55% were shared epitope positive. Smoking >10 pack-years was associated with inflammatory joint signs at baseline (odds ratio [OR] 1.89 [95% confidence interval (95% CI) 1.26-2.82]) and at 2 years (OR 2.66 [95% CI 1.01-7.03]), compared to never smokers. There was a significant interaction between smoking and age with regard to risk of inflammatory joint signs (P = 0.02). FDRs younger than 50 years with >10 pack-years had the highest risk of inflammatory joint signs (OR 4.39 [95% CI 2.22-8.66], compared to never smokers younger than 50 years). CONCLUSION: In a high-risk cohort of FDRs, smoking and age were associated with both prevalent and incident inflammatory joint signs at sites typical for RA. Further prospective investigations of the factors affecting the transitions between preclinical RA phases are warranted.
Source: Arthritis & Rheumatology
DOI: 10.1002/art.39630
Authors: Jeffrey A. Sparks, Shun‐Chiao Chang, Kevin D. Deane, Ryan W. Gan, M. Kristen Demoruelle, Marie L. Feser, LauraKay Moss, Jane H. Buckner, Richard M. Keating, Karen H. Costenbader, Peter K. Gregersen, Michael H. Weisman, Ted R. Mikuls, James R. O'Dell, V. Michael Holers, Jill M. Norris, Elizabeth W. Karlson
Institutions: Brigham and Women's Hospital, Harvard University, University of Colorado Anschutz, Colorado School of Public Health, Benaroya Research Institute, Scripps Health, Feinstein Institute for Medical Research, Cedars-Sinai Medical Center, VA Nebraska Western Iowa Health Care System, University of Nebraska Medical Center
Language: English
Subfield: Rheumatology
Field: Medicine
Domain: Health Sciences
Open Access status: green
Awards: The Role of the Lung in the Initiation of Rheumatoid Arthritis, UCLA Clinical and Translational Science Institute, G2471007954, G2663518188, Benaroya Research Institute/UCDHSC Autoimmune Cooperative Study Group, UCLA Clinical and Translational Science Institute, NIAMS Multidisciplinary Clinical Research Center, Novel Biomarkers and Prediction Models for Rheumatoid Arthritis, General Clinical Research Center, RA-Related Autoantibodies in Healthy FDR of RA Patients, Family History, Genes, Environment and G X E Interaction in Predicting RA Risk, General Clinical Research Center, Genetics, Exposures, and RA-Related Autoimmunity, Prevention Center U01: Early Targets for Antigen-Specific Tolerance Induction in Preclinical Rheumatoid Arthritis, Research Training in Rheumatology
OpenAlex ID: W2489565242