Abstract 8 — Risk of Liver Injury in Psoriasis and Rheumatoid Arthritis is Associated with Metabolic Risk Factors Rather than Methotrexate and Leflunomide

Objectives To assess the associations of hepatic injury and fibrosis in patients with psoriasis (PsO) and rheumatoid arthritis (RA). Methods A total of 318 patients attending dermatology and/or rheumatology out-patient clinics in Queen Mary Hospital, with clinical diagnosis of PsO, psoriatic arthritis (PsA) or RA were consecutively recruited from July 2020 to August 2022. Demographic data, comorbidities, and medications were recorded. Body mass index (BMI) was measured. Serum biomarkers for hepatic injury including autotaxin, matrix metalloproteinase (MMP) 3, MMP 8, and MMP 9 were determined. Transient elastography (TE) was performed to determine liver stiffness measure (LSM) and controlled attenuation parameter (CAP). Regression models were built to determine the association between methotrexate and leflunomide cumulative dosage, serum biomarkers and TE scores. Results A total of 67 (20.4%) patients had LSM>7.1 kPa. Multivariate linear regression showed methotrexate cumulative dosage was associated with autotaxin level (B=4.77, 95% CI 1.39; 8.15, p=0.001). There was no association between methotrexate cumulative dosage and MMP 3, MMP 8, MMP 9, LSM, CAP. There was also no association between leflunomide cumulative dosage and autotaxin, MMP 3, MMP 8, MMP 9, LSM, CAP. BMI (B=6.18, 95% CI 4.95; 7.41, p<0.001), hypertension (B=18.98, 95% CI 4.15; 31.82, p=0.01), hyperlipidaemia (B=20.21, 95% CI 3.50; 36.92, p=0.02) were associated with CAP. Conclusion Methotrexate and leflunomide have minimal hepatic risk in patient with PsO and RA. Metabolic risk factors had strong associations with hepatic injury.