Is There a Link Between Non-Alcoholic Fatty Liver Disease and Benign Prostate Hyperplasia/Lower Urinary Tract Symptoms: A Systematic Review and a Meta-Analysis.

Background: Prostatic growth has been thought to be the systemic manifestation of some metabolic derangements in recent studies. Nonalcoholic fatty liver disease (NAFLD), a hepatic manifestation of the metabolic syndrome, might be closely linked with benign prostate hyperplasia and lower urinary tract symptoms (BPH/LUTS). Several studies have been conducted regarding NAFLD and BPH/LUTS association. However, the results are yet to reach a clear conclusion. We aimed to gather these studies' results to make a more robust analysis through a systematic review and meta-analysis. Methods: We systematically searched Pubmed-Medline, Cochrane Library, and Science Direct databases. We excluded all experimental studies, case reports, and reviews. Our search was restricted to the English language. We used standard mean difference for BPH/LUTS-related parameters. We identified the study qualities by the Newcastle-Ottawa Scale. We conducted a publication bias analysis. Results: A total of six studies involving 7089 participants fulfilled the inclusion criteria. Our meta-analysis revealed that patients with NAFLD have larger prostate volume [0.553 (0.303-0.802), P  ˂ 0.001; Q  = 97.41; P -value for heterogeneity =  P  < 0.0001; I 2  = 94.86%]. However, the summary effect size of the other parameters of BPH/LUTS (prostate-specific antigen and international prostate symptom score) computed in our meta-analysis did not yield significant results. Conclusions: The prostate size was larger in patients with NAFLD, but the meta-analysis did not reach a significant result for LUTS among the studies. These results should be tested with well-designed studies, in particular, to clarify the association of LUTS with NAFLD.