Systematic review with meta-analysis: de novo non-alcoholic fatty liver disease in liver-transplanted patients

Background: De novo non-alcoholic fatty liver disease (NAFLD) in liver-transplanted patients for cirrhosis not due to non-alcoholic steatohepatitis (NASH) is becoming a growing phenomenon. Aims: We performed a systematic review and evaluated the prevalence of this event and possible associated factors. Methods: A literature search in medical databases (PubMed, MEDLINE/OVIDSP, Science Direct and EMBASE) was performed in March 2017. Relevant publications were identified in most important databases. We estimated the pooled prevalence of NAFLD and NASH in patients with liver transplant. The data have been expressed as proportions/percentages, and 95% confidence intervals (CI) were calculated, using the inverse variance method. Odd ratios (OR) and 95% confidence intervals (95% CI) were estimated. Results: Twelve studies were selected, enrolling 2166 subjects overall undergoing post-liver transplant biopsy. The pooled weighted prevalence of de novo NAFLD was 26% (95% CI 20%-31%). The pooled weighted prevalence of NASH was 2% (95% CI 0%-3%). The highest prevalences of de novo NAFLD were found for patients transplanted for alcoholic cirrhosis (37%) and cryptogenic cirrhosis (35%) and for patients taking tacrolimus (26%). Tacrolimus showed a risk of NAFLD similar to ciclosporin (OR = 1.02, 95% CI 0.3-3.51). Conclusions: Patients undergoing liver transplant are more prone to experience diabetes, hypertension or dyslipidaemia, and NAFLD may be an important element in this context. In this study, we show how the prevalence of NASH tends to remain significant and similar to the general population. Moreover, this study suggests a possible association with specific transplant indications. Further studies are required to confirm these findings.