Smoking cessation may reduce risk of rheumatoid arthritis
Analysis of data from the Nurses’ Health Studies demonstrates for first time that behavior change can delay or even prevent the most severe form of rheumatoid arthritis.
Smoking is an important risk factor for developing the most common form of rheumatoid arthritis (RA) and other inflammatory diseases, but a critical question remains: Can those who quit smoking delay or prevent RA or have they permanently and irrevocably altered their risk of the disease? Given that hypothesis, a new study by investigators from Brigham and Women's Hospital leverages data from the Nurses' Health Studies led to new research with the findings recently appear in Arthritis Care & Research.
Sustained smoking cessation demonstrates for the first time that changing behavior can reduce risk of developing seropositive RA, the more severe form of the disease. “Ours is the first study to show that a behavior change can reduce risk for seropositive RA,” said corresponding author Jeffrey Sparks, MD, MMSc, of the Division of Rheumatology, Immunology and Allergy at the Brigham. “Risk isn't just about genes and bad luck – there’s a modifiable environmental component to the onset of this disease and a chance for some people to reduce their risk or even prevent RA.”
Sparks and colleagues used data from the original Nurses’ Health Study, established in 1976, and Nurses’ Health Study II, a second cohort established in 1989. Both groups included RNs from across the U.S. who filled out health surveys every two years with questions that included information about smoking and health status.
From among more than 230,000 participants in this analysis, the researchers found that 1,528 developed RA. The team identified 969 “seropositive” as opposed to “seronegative” cases. Patients with seropositive RA have auto-antibodies related to RA, and generally have more severe disease manifestations, including joint deformities and disability.
For seropositive RA, risk began to go down about five years after women quit smoking and continued to decrease the longer they stayed non-smokers. Participants who quit for good reduced their risk of seropositive RA by 37 percent after 30 years.
The team did not find any association between seronegative RA and smoking, adding further evidence to the theory that seronegative and seropositive RA may be two distinct diseases with distinct risk factors.
"One of the lessons here is that it takes sustained smoking cessation to reap the full benefit," said Sparks.
Sparks thinks that smoking may affect a preclinical disease process that leads to the formation of RA-related auto-antibodies and increases inflammation.
