Smoking at onset of rheumatoid arthritis (RA) and its effect on disease activity and functional status: experiences from BARFOT, a long-term observational study on early RA
Objectives: To assess the effects of smoking on disease outcome in a large cohort of patients with early rheumatoid arthritis (RA). Methods: Between 1996 and 2004, 1787 adult patients (disease duration <= 1 year) were included in the BARFOT early RA study in Sweden. Smoking status was recorded at inclusion in the study. Disease Activity Score using 28 joint counts (DAS28), C-reactive protein (CRP)
