We've all been told that smoking is harmful to one's health. Smoking has been shown to increase the risks of heart disease and strokes. Smoking has even been linked as an environmental trigger for developing rheumatoid arthritis. People who are genetically predisposed to developing RA are much more likely to actually do so if they also smoke. It has also been shown that smokers with RA are more likely to have rheumatoid nodules and vasculitis. But other studies have sometimes shown differnet affects -- indicating that heavy smoking has an anti-inflammatory, protective effect on the joints, mitigating joint damage. In addition, several other studies have come out in recent months dealing with the effects of smoking on people who already have rheumatoid arthritis.
In one study, scientists in the UK found that patients with RA who smoke have a lower body mass index (BMI) and lower body fat (BF) than patients who are nonsmokers or ex-smokers. Also, heavy smokers had a greater loss of muscle mass that people who smoke fewer cigarettes or who don't smoke. The 392 people in the study (290 female) averaged 62 years old and had a disease duration of 4-18 years. The study included current smokers, ex-smokers and never-smokers. In additions, 50% of the ex-smokers were obese, compared with 39% of the never-smokers and 30% of the smokers. This reflects the common knowledge that smoking is an appetite suppressant and that people who smoke tend to have lower muscle mass and lower body fat than people who don't smoke. It also reflects the data showing that people who quit smoking often struggle with weight gain. The researchers stressed that physicians should advise their patients with RA against smoking. However, they also stressed that for persons with RA, smoking cessation regimens should include more lifestyle counseling, particularly for weight control and exercise. Weight control and physical activity are particularly important for maintaining joint integrity and managing RA disease activity.
In the other study, conducted in Germany, researchers investigated whether smoking affects disease activity and joint destruction and results in a higher need for DMARDs. The study included about 1,000 patients in over 50 rheumatology clinics in Germany. Overall, they found that people with RA who smoke do have a higher need for DMARDs and feel worse than patients who don't smoke, but that they didn't have higher disease activity scores or any more joint damage than the non-smokers. Of the 27% of the people in the study who were current smokers, 71% had a positive rheumatoid factor. This is more than both ex-smokers and nonsmokers. It should also be noted that the current smokers tended to be younger and of better general health than the ex-smokers and nonsmokers.
The heaviest smokers had the highest pain ratings and the lowest response rates to DMARDs. They also had more often used DMARD combinations and biologic drugs to control their RA. Over the three years of the study, the current smokers used significantly more biologic and non-biologic DMARDs than the other study participants. They concluded that this increased need for DMARDs may show either that smoking weakens the potency of RA drugs or that more drugs may be needed to control the smokers' more severe pain and greater disease activity.
Overall, both studies point toward the benefits of quitting smoking for people with RA or who are predisposed to developing RA. Aside from the general health affects of smoking, it can affect the type and number of drugs needed to manage one's disease. Current smokers who want to quit, might want to consider talking to their doctors about joining or developing a smoking cessation program that targets their individual needs, especially in the areas of weight management and exercise and managing their disease activity.
May 2008 issue, Arthritis Research and Therapy
June 2008 issue, Rheumatology