Study objectives: To determine if treatment with low-dose methotrexate spares oral steroids in adult, steroid-dependent, asthmatic patients.
Design: Articles identified by computer search were excluded if they (1) did not contain original data relating to the primary question, (2) had no controls, or (3) described subjects younger than 18 years of age.
Measurements: From each article, the following was abstracted: reference citation; type of control; whether study incorporated a run-in period in which the baseline level of prednisone was reduced to the lowest possible dose; dosage and length of methotrexate therapy; baseline dosage; and type of steroid. Also, the following was determined during both placebo and methotrexate arms of each study: steroid dosage, FEV1, serious side effects, and alteration in level of serum aspartate aminotransferase.
Results: Eleven eligible studies were identified. Methotrexate treatment resulted in a decrease in prednisone or prednisolone usage by an average of 4.37 mg/d or 23.7% of the initial dosage. The summary effect size in standard deviations (SDs) was −0.53 (95% confidence interval=−0.29 to −0.77). Subgroup analysis showed that patients treated with prolonged (6-month) therapy with methotrexate, those with low long-term usage of steroids (≤20 mg/d), and those whose study design incorporated a run-in period, tended to have the greatest steroid-sparing effects with methotrexate.
Conclusions: Low-dose methotrexate has a significant steroid-sparing effect in steroid-dependent asthmatic patients. The greatest effect was evident in patients in whom an effort was made to reduce baseline steroid dosage and in whom methotrexate was used for 24 weeks.