The economic burden of fibromyalgia: comparative analysis with rheumatoid arthritis.

Objective: To quantify and compare direct costs, utilization, and the rate of comorbidities in a sample of patients with fibromyalgia (FM), a poorly understood illness associated with chronic widespread pain that is commonly treated by rheumatologists, to patients with rheumatoid arthritis (RA), a well studied rheumatologic illness associated with inflammatory joint pain. Patients with both illnesses were isolated and reported as a third group. A secondary analysis of work loss was performed for an employed subset of these patients.