Diagnosing late onset rheumatoid arthritis, polymyalgia rheumatica, and temporal arteritis in patients presenting with polymyalgic symptoms. A prospective longterm evaluation.

Objective: . To examine for demographic and clinical differences between late onset rheumatoid arthritis (LORA), polymyalgia rheumatica (PMR), and temporal arteritis (TA) patients presenting with polymyalgic symptoms (PMS) and to identify baseline clinical and laboratory features that would lead to a more accurate final diagnosis.

Methods: Three hundred forty-nine consecutive patients with new onset of symptoms suggestive of LORA, PMR, or TA presenting at or above age 60 years were enrolled in a prospective study.