Prevalence and risk factors for liver fibrosis detected by transient elastography or shear wave elastography in inflammatory arthritis: a systematic review.

OBJECTIVES Emerging technologies for monitoring subclinical liver fibrosis include transient elastography (TE) and shear wave elastography (SWE). A systematic review was conducted to assess the prevalence and report on predictors of liver fibrosis as detected by these technologies in inflammatory arthritis (IA) patients, including rheumatoid arthritis, spondyloarthritis and juvenile idiopathic arthritis. METHODS MEDLINE, EMBASE and Web of Science were searched from inception to 06/27/2016 using search terms for IA or DMARDs and TE/SWE. Studies reporting on prevalence and/or risk factors for liver fibrosis as detected by TE/SWE were included. A meta-analysis was not conducted due to study heterogeneity. RESULTS Seven cross-sectional and three case-control studies were included. The cut-off values to define liver fibrosis ranged from 5.3-8.6 kPa. The prevalence of liver fibrosis in RA detected by TE/SWE ranged from 3-23%, with higher prevalence found in studies using a 5.3kPa cut-off. In two studies fibrosis was reported in 16-17% of PsA patients with no JIA studies identified. Obesity was the most consistently reported independent predictor of fibrosis in three studies. Liver function tests (LFTs) were found to independently predict increased liver stiffness in one study, while cumulative dose of either methotrexate or leflunomide were predictors in two studies. CONCLUSIONS Methotrexate or leflunomide cumulative dose was not consistently reported as an independent predictor of liver fibrosis; whereas, obesity was more consistently identified. Of note, LFTs did not consistently predict elevated TE/SWE measures. Further studies are needed to evaluate the prevalence and predictors of liver fibrosis and to explore the utility of using TE/SWE in IA patients.