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Comment
. 2018 Feb;38(2):313-314.
doi: 10.1007/s00296-017-3902-3. Epub 2017 Dec 5.

The impact of smoking on disease measures in rheumatoid arthritis: the need for appropriate adjustment of time-varying confounding

Milena A Gianfrancesco  1 , Jinoos Yazdany  2 , Gabriela Schmajuk  2   3
Affiliations
Comment

The impact of smoking on disease measures in rheumatoid arthritis: the need for appropriate adjustment of time-varying confounding

Milena A Gianfrancesco et al. Rheumatol Int. 2018 Feb.

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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Figures

Figure 1
Figure 1
Directional acyclic graph demonstrating the longitudinal relationship between current smoking and disease activity over time
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References

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