Psoriasis patients with diabetes type 2 are at high risk of developing liver fibrosis during methotrexate treatment

Background/Aims We investigated the impact of diabetes mellitus type 2, overweight, alcohol over-consumption, and chronic hepatitis B or C as risk factors, for liver fibrosis in psoriasis patients treated with methotrexate. Methods One hundred and sixty-nine liver biopsies from 71 patients who underwent liver biopsies as part of the monitoring of methotrexate treatment for psoriasis were reviewed. Fibrosis, steatosis and inflammation were staged according to the NAFLD activity score. Results Twenty-six patients had one or more of the risk factors and 25 (96%) of these (median cumulative dose methotrexate 1500 mg) developed liver fibrosis. Of those without risk factor, 26 (58%) (p = 0.012) developed fibrosis (median cumulative dose methotrexate 2100 mg). Ten (38%) of the patients with risk factor(s) had severe fibrosis (stage 3–4) (mean cumulative dose methotrexate 1600 mg), while four (9%) (p = 0.0012) of those without risk factors had severe fibrosis (median cumulative dose methotrexate 1900 mg). Conclusions Patients with methotrexate treated psoriasis and risk factors for liver disease, especially diabetes type 2 or overweight, are at higher risk of developing severe liver fibrosis compared to those without such risk factors, even when lower cumulative methotrexate doses are given.