A Multi-Center Double-Blind Crossover Comparison Study of Naproxen and Aspirin in Patients with Rheumatoid Arthritis

Abstract

This paper presents the results of a multi-center double-blind crossover study of naproxen and aspirin in 119 adult patients (mean age 52) with rheumatoid arthritis. All patients had definite or classical rheumatoid arthritis (ARA criteria) and fulfilled specific criteria for active disease. Non-steroidal anti-inflammatory medication and analgesics were discontinued at onset of the study and replaced randomly by either naproxen (500 mg/day) or aspirin (3.6 g/day). Each drug was then given in sequence for a six week study period. Patients already receiving corticosteroid and/or gold therapy were maintained at constant dose throughout the study. Evaluations were carried out at two week intervals and included questioning of patients for side-effects, investigator and patient global evaluation of drug efficacy and tolerance and measurements of grip strength, walking time, number of clinically active joints, duration of morning stiffness and time to fatigue. Laboratory parameters were closely monitored during the study. There was no significant difference in global evaluation of efficacy or individual measures of efficacy between aspirin and naproxen although physicians' global evaluation tended to favor naproxen. Sedimentation rate was lower on aspirin (naproxen 43.1 mra/h, aspirin 38.7 mm/h, p =0.017). Naproxen, 250 mg twice daily, was significantly better tolerated than aspirin, 900 mg four times daily. Mild, moderate and severe side-effects were less frequent with naproxen (p=2×10−4) by McNemer's Sign test). The incidence of heartburn was significantly lower on naproxen (p=2x10−4) and significantly fewer patients terminated their 6 week study period on naproxen than on aspirin (p =0.007).