Serious infections in a population‐based cohort of 86,039 seniors with rheumatoid arthritis

OBJECTIVE: To assess risk and risk factors for serious infections in seniors with rheumatoid arthritis (RA) using a case-control study nested within an RA cohort. METHODS: We assembled a retrospective RA cohort age ≥66 years from Ontario health administrative data across 1992-2010. Nested case-control analyses were done, comparing RA patients with a primary diagnosis of infection (based on hospital or emergency department records) to matched RA …