(Reuters Health)—Adults who quit smoking decades ago may have a lower risk of rheumatoid arthritis (RA) than people who gave up cigarettes more recently, a U.S. study suggests.
Smoking has long been linked to an increased risk of RA, and quitting can reduce this risk. But the new study offers fresh evidence that years of cessation can pay off more than just a brief period without cigarettes.
“These results provide evidence for those at increased rheumatoid arthritis risk to quit smoking since this may delay or even prevent the onset of rheumatoid arthritis,” said senior study author Jeffrey Sparks, MD, MMSc, of Brigham and Women’s Hospital and Harvard Medical School, Boston.
Also, Dr. Sparks says by email, while quitting is the best way to reduce RA risk, cutting back on smoking “should also help lessen the risk.”
Dr. Sparks and colleagues examined up to 38 years of data on more than 230,000 women in the Nurses Health Study, including 1,528 who developed RA.
Current smokers were also 67% more likely to develop seropositive disease, which tends to have a more severe course with more joint deformities, disability and inflammation.
Compared with women who quit smoking within the previous five years, women who quit at least three decades ago were 37% less likely to develop seropositive RA.
Women in the study were predominantly white and well-educated, and it’s possible that results might be different for other groups of people, the study authors note. Smoking was also only assessed every two years, and changes in smoking habits that occurred between assessments may have been missed.
But the results should still give smokers yet another reason to quit, says Kaleb Michaud, PhD, a researcher at the University of Nebraska Medical Center, Omaha, who wasn’t involved in the study.
“There’s a clear dose-dependency seen between the cumulative amount of smoking and the risks for future RA,” Dr. Michaud says by email.
“There’s little evidence that smoking cessation reverses RA—it’s still incurable and a chronic source of pain and suffering for many people,” Dr. Michaud adds. “But current smokers could at least reduce this risk by smoking fewer and fewer cigarettes.”
- Liu X, Tedeschi SK, Barbhaiya M, et al. Impact and timing of smoking cessation on reducing risk for rheumatoid arthritis among women in the Nurses’ Health Studies. Arthritis Care Res (Hoboken). 2019 Feb 21. [Epub ahead of print]