Background and Aims: Methotrexate is used to treat a variety of inflammatory diseases. Despite its effectiveness, there are concerns about the risk of liver fibrosis, although the relationship has been poorly understood. In this context we reviewed results of FibroScan for Liver Stiffness Measurement (LSM) in patients prescribed Methotrexate over 12 years.
Method: In a retrospective, single-centre study, patients on Methotrexate with suspicion of liver injury were identified. Data was collated between October 2008 and December 2020. LSM was categorised as <8kPa, 8-12kPa and >12kPa. The AST-to-ALT ratio, APRI and FIB-4 index were calculated and P3NP value, if available, recorded. A reliable FibroScan was defined as an IQR percentage of median LSM ≤30%, or if LSM <7.1kPa.
Results: 369 LSMs were obtained, of which 325 (88.1%) were reliable. The most common indication for Methotrexate was psoriasis (68.9%). 25.8% had abnormal LSM (>8kPa) with 10.8% having high risk scores >12kPa. On logistic regression analysis diagnosis of diabetes, use of XL probe and FIB-4 index were related to a LSM >12kPa. In total there were 44 deaths (15.9%) after a median follow-up of 2767 (2536, 3011) days from index assessment. Two deaths were liver-related (decompensated ascites); both patients had a LSM >12kPa. The 33 patients with a LSM >12kPa there were just 3 (9.1%) with liver related events: the 2 deaths as above and 1 patient with bleeding from portal hypertensive gastropathy. 48 patients had more than 1 LSM: median change in LSM was -0.3 (-0.7, 0.3) and change in FIB-4 +0.04 (-0.08, 0.08).
Conclusion: Liver-related events are rare in patients taking Methotrexate and occurred only in those with a baseline LSM >12kPa. FIB-4 index and markers of metabolic dysfunction were related to high LSM values. Clinically significant change in LSM on interval scanning after a median of 2 years was rare.