Smokers' risk of RA doubled
Heavy smokers are almost twice as likely to develop rheumatoid arthritis as patients who have never smoked, according to a study. The risk is greater in men and remains for 10-19 years after cessation, the researchers said.
The study looked at 679 cases of rheumatoid arthritis and 847 controls in Sweden over a four-year period. Smoking habits among
all patients were recorded and whether the
cases tested positive for rheumatoid factor (RF), a marker present in about 80 per cent of patients with rheumatoid arthritis.
The results, which appear in Annals of the Rheumatic Diseases (September), showed men and women who smoked or had smoked and tested positive for RF were 70 to 90 per cent more likely to develop rheumatoid arthritis than those who never smoked.
The increased risk was only apparent in
patients who had smoked for longer than 20 years and smoked six to nine cigarettes a day.