Clinical and laboratory effects of prolonged therapy with sulfasalazine, gold or penicillamine: the effects of disease duration on treatment response.

Serial observations for up to 5 years of clinical score (a subjective global assessment), serum C-reactive protein (CRP) and the erythrocyte sedimentation rate (ESR) were analyzed in 3 groups of patients with active rheumatoid arthritis (RA) requiring treatment with a second line drug. The groups comprised 315 patients (243 women, 72 men) who had sulfasalazine (SAS); 203 patients (141 women, 62 men) who had sodium aurothiomalate (gold) and 163 patients (131 women, 32 men) who had penicillamine. The groups matched in most respects but the gold group had a smaller proportion of women, a shorter median disease duration and a higher median CRP than the remaining 2 groups. The penicillamine group contained a higher proportion of seropositive patients. In each group there were significant improvements in clinical score, CRP and ESR for all time points from 6 to 30 months; these improvements were maintained for longer (up to 60 months for SAS) in the SAS and gold groups but the differences between the drugs after 30 months were probably a consequence of falling number of patients, not differing drug potencies. The mean ESR and CRP levels fell to about 30 mm/h and 20-30 mg/l, respectively. Response was defined as (1) treatment duration greater than 6 months, (2) clinical score improvement greater than 4 by 6 months, (3) ESR fall to less than 30 mm/h by 6 months. By these criteria 142 of 681 patients (20.9%) responded; the response rates were SAS 20.3%, gold 24.1%, penicillamine 17.8%.(ABSTRACT TRUNCATED AT 250 WORDS)