Abstract
In a recent publication, Quintana-Dunque et al. studied patients with early onset rheumatoid arthritis (RA) and showed that baseline smoking status was inversely associated with disease activity and disability at 36 months. The authors conclude that smoking may not be as deleterious as previously considered in RA disease course. However, the authors fail to highlight several limitations of study design and analysis, including time-varying confounding, which may have a direct impact on results and corresponding conclusions.
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References
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This work was supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health (Grant numbers F32 AR070585 to M.G. and K23 AR063770 to G.S.); and the Agency for Healthcare Research and Quality (Grant number R01 HS024412 to J.Y.). Drs. Yazdany and Schmajuk are also supported by the Russell/Engleman Medical Research Center for Arthritis. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Agency for Healthcare Research and Quality or National Institutes of Health.
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This comment refers to the article available at https://doi.org/10.1007/s00296-017-3845-8.
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Gianfrancesco, M.A., Yazdany, J. & Schmajuk, G. The impact of smoking on disease measures in rheumatoid arthritis: the need for appropriate adjustment of time-varying confounding. Rheumatol Int 38, 313–314 (2018). https://doi.org/10.1007/s00296-017-3902-3
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DOI: https://doi.org/10.1007/s00296-017-3902-3