Skip to main content

Research Repository

Advanced Search

What is the incidence of methotrexate or leflunomide discontinuation related to cytopenia, liver enzyme elevation or kidney function decline?

Mallen

What is the incidence of methotrexate or leflunomide discontinuation related to cytopenia, liver enzyme elevation or kidney function decline? Thumbnail


Authors



Abstract

OBJECTIVES: To examine incidence of treatment changes due to abnormal blood-test results and, to explore rates of treatment changes due to liver, kidney and haematological blood-test abnormalities in autoimmune rheumatic diseases (AIRD) treated with low-dose methotrexate or leflunomide. METHODS: Data for people with AIRDs prescribed methotrexate or leflunomide were extracted from the Clinical Practice Research Datalink. Participants were followed-up from first prescription of methotrexate or leflunomide in primary-care. Primary outcome of interest was drug discontinuation, defined as a prescription gap of?=?90 days following an abnormal (or severely abnormal) blood-test result. Dose reduction was examined between consecutive prescriptions. Incidence rates per 1,000 person-years were calculated. RESULTS: 15,670 and 2,689 participants contributing 46,571 and 4,558 person-years follow-up were included in methotrexate and leflunomide cohorts respectively. The incidence of methotrexate and leflunomide discontinuation with abnormal (severely abnormal) blood-test was 42.24(6.16) and 106.53(9.42)/1,000 person-years in year-1, and 22.44(2.84) and 31.69(4.40)/1,000 person-years respectively thereafter. The cumulative incidence of methotrexate and leflunomide discontinuation with abnormal (severely abnormal) blood-tests was 1 in 24(1 in 169), 1 in 9(1 in 106) at 1-year; and 1 in 45(1 in 352), 1 in 32(1 in 227) per-year respectively thereafter. Raised liver enzymes were the commonest abnormality associated with drug discontinuation. Methotrexate and leflunomide dose reduction incidence were comparable in year-1, however, thereafter methotrexate dose was reduced more often than leflunomide (16.60(95% CI; 13.05-21.13) vs. 8.10(95% CI; 4.97-13.20)/1,000 person-years). CONCLUSION: Methotrexate and leflunomide were discontinued for blood-test abnormalities after year-1 of treatment, however, discontinuations for severely abnormal results were uncommon.

Acceptance Date Mar 5, 2021
Publication Date Mar 16, 2021
Publicly Available Date Mar 28, 2024
Journal Rheumatology
Print ISSN 1462-0324
Publisher Oxford University Press
DOI https://doi.org/10.1093/rheumatology/keab254
Keywords Autoimmune rheumatic diseases, Blood-test monitoring, Leflunomide, Methotrexate
Publisher URL https://doi.org/10.1093/rheumatology/keab254