Experience with low-dose methotrexate: toxicity, tolerability and effect on conventional patterns of drug therapy for inflammatory arthritis.

Abstract

This study examines the 10-year experience of a single rheumatologist in the treatment of inflammatory arthritis with low dose methotrexate (MTX). The toxicity and tolerability of MTX has been assessed and the effect of this drug on the conventional pattern of pharmacotherapy for inflammatory arthritis has been examined. The case records of all 99 patients with inflammatory arthritis prescribed MTX in the ten-year period up to the end of 1991 were reviewed. Adverse reactions, duration of therapy, overall efficacy, as well as details of previous and concurrent drug therapy were noted. MTX was clinically beneficial in 85 patients. Of these, on a four point scale, 68 patients claimed moderate or marked benefit. MTX was discontinued in 20 patients; in 12 the cause was an adverse reaction. Many more (47) patients suggered mild reactions not resulting in drug withdrawal. In our patients MTX has a favourable tolerability record and has been continued in 83%, 69% and 50% after 1, 2, and 5 years of treatment respectively. The use of MTX increased markedly towards the end of the 10-year study period. Sixty-two patients were started on MTX either in 1990 or 1991. The mean number of other disease modifying drugs used before MTX has declined from a peak of 2.40 in 1987 in 1987 to 1.52 in 1991. Similarly, the percentage of patients prescribed concurrent oral corticosteroids has declined from 88% to 52% from 1987 to 1991. In our experience MTX is effective, has a favourable toxicity and tolerability record. In this practice we have identified a trend to increased use of MTX earlier in the course of drug treatment of inflammatory arthritis. The concurrent use of oral corticosteroids appears to be declining.