Cigarette smoking is a well-established risk factor for developing rheumatoid arthritis (RA), and previous research has shown that ever-smokers have a 40 percent higher risk of RA than never-smokers. Little is known however, regarding the dose-response relationship between the quantity of cigarette smoking and the risk of RA.
In a recent meta-analysis, researchers have found a non-linear dose-response trend. The risk of developing RA increased significantly with increasing number of pack-years (a unit of quantifying cigarette smoking, where a pack year is defined as smoking 20 cigarettes a day for one year). This correlation occurred up to 20 pack-years, after which the relative risk stabilised, even for those individuals who smoked more than 40 pack-years.
There appears to be a non-linear dose relationship between lifelong smoking and RA, with risk increasing up to 20 pack years.
Written by Stephanie Harriman, Deputy Medical Editor for BioMed Central.
More available here.
Arthritis Research & Therapy 2014, 16:R61
Go to article >>