Safe use of antirheumatic agents in patients with comorbidities.

The burden of comorbid diseases is high among patients with rheumatoid arthritis (RA). These are often systemic manifestations of RA but may be chronic conditions that predate or develop post-RA diagnosis. Increased mortality in RA is predominantly from nonarticular causes. The expanded armamentarium of disease-modifying drugs and biologics available has revolutionized management of articular disease but has made safe treatment of RA more complex. Drug-induced organ injury and side effects need to be kept in mind when initiating or modifying therapy.