Previous research indicates that rheumatoid arthritis (RA) is associated with significant morbidity and mortality, affecting more than 3 million adults in the US. Prior studies have also found that former smokers had increased risk for RA when compared with never smokers. However, it remains unclear whether smoking cessation might affect RA risk.

To better assess this potential relationship, Jeffrey A. Sparks, MD, MMSc, and colleagues investigated the impact and timing of smoking cessation on developing RA and serologic phenotypes. For a study published in Arthritis Care & Research, the research analyzed data on more than 230,000 women, of whom 1,500 developed RA during more than 6 million person‐years of follow‐up.

Compared to never smoking, current smoking increased risk for all RA (multivariable hazard ratio [HR], 1.47) and seropositive RA (HR, 1.67), but not seronegative RA (HR, 1.20). Increasing smoking pack‐years was associated with increased trend of risk for all RA and seropositive RA. With increasing duration of smoking cessation, a decreased trend was observed in risk for all RA and seropositive RA. When compared with recent quitters (<5 years), those who quit at least 30 years prior had an HR of 0.63 for seropositive RA. However, a modestly elevated RA risk was still detectable 30 years after quitting smoking (all RA: HR, 1.25).

“Ours is the first study showing that a behavior change, rather than only genetics or bad luck, may actually reduce RA risk,” says Dr. Sparks. “This also provides more evidence that smoking may play a key role in the pathogenesis of seropositive RA.”