Liver fibrosis in inflammatory arthritis patients treated with methotrexate and hydroxychloroquine: A FIB-4 index analysis

To evaluate the risk of liver fibrosis and associated factors with the non-invasive fibrosis score-4 (FIB-4) index in patients with inflammatory arthritis using methotrexate (MTX).

Patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA) who were followed up in the rheumatology outpatient clinic, who were on methotrexate only and for whom FIB-4 index was could be calculated at methotrexate initiation and follow-up were included. The FIB-4 index was calculated according to the following formula: age (years) × AST(IU/L)/(platelet count(10 (9)/L) × √ALT(IU/L)). The patients' demographics, comorbidities, other treatments, cumulative MTX dose, and reasons for MTX cessation were assessed. For the multivariate analysis, possible factors associated with intermediate-high risk FIB-4 index at last visit were determined.

A total of 107 patients were enrolled in the study, of whom 82 (76.6%) had RA and 25 (23.4%) had PsA. At the initiation of MTX, 24 (22.4%) patients had intermediate-high risk FIB-4 index. Comorbidities and the rate of ≥3-4 Charlson comorbidity index were more common in patients with intermediate-high risk FIB-4 index. A total of 37 (34.5%) patients had intermediate-high risk FIB-4 index at the last visit after median 3.6 (0.3-22.06) years follow-up. The median cumulative MTX dose was 2550 mg (1050-13.991). Cumulative MTX dose [OR 1.18 (1.01-1.33), p = .03] and diabetes mellitus [OR 4.60 (1.74-12.50), p = .002] were associated factors with intermediate-high risk FIB-4 index. The concomitant use of hydroxychloroquine (HCQ) was found to be a low-risk factor for FIB-4 index [OR 0.28 (0.10-0.78) p = .015].

The FIB-4 index is a non-invasive method that can be used in daily rheumatology practice for the evaluation and follow-up of patients who will use methotrexate. Comorbidities and cumulative MTX dose seem to be related with the risk of liver fibrosis. Concomitant use of HCQ with MTX may reduce the risk of liver fibrosis.