RESUMEN
Background: The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, is increasing globally. Noninvasive methods, such as bioelectrical impedance analysis (BIA), which measures body composition, including visceral fat, are gaining interest in evaluating MASLD patients. Our study aimed to identify factors associated with significant liver fibrosis, compare noninvasive scores, and highlight the importance of visceral fat measurement using BIA. Methods: MASLD patients seen in our out-patient department underwent comprehensive evaluations, including liver stiffness using transient elastography, body composition analysis using BIA, and metabolic measurements. Significant fibrosis was defined as a liver stiffness measurement of ≥8.2 kPa. Using multivariate analysis, we identified factors associated with significant liver fibrosis and compared four noninvasive scores with a novel diabetes-visceral fat 15 (DVF15) score. Results: We analyzed data from 609 MASLD patients seen between February 2022 and March 2023. The median age was 43 years (81% male). Among these, 78 (13%) had significant fibrosis. Patients with significant fibrosis had higher rates of type 2 diabetes (41% vs 21%, P < 0.001) and elevated levels of aspartate aminotransferase, alanine aminotransferase, hemoglobin A1c, Fibosis-4, aspartate-aminotransferase-to platelet-ratio index, and NAFLD fibrosis scores. They also exhibited higher visceral and subcutaneous fat. Binary logistic regression revealed type 2 diabetes and a visceral fat level of >15% as associated with significant liver fibrosis. Additionally, the DVF15 score, combining these factors, showed a modest area under the receiver operating characteristic curve of 0.664 (P < 0.001). Conclusion: Our study identified diabetes and high visceral fat as factors associated with significant liver fibrosis in MASLD patients. We recommend that visceral fat measurement using BIA be an essential part of MASLD evaluation. The presence of either diabetes or a visceral fat level of >15% should prompt clinicians to check for significant fibrosis in MASLD patients. Further research is warranted to validate our findings and evaluate the utility of the DVF15 score in larger cohorts and diverse populations.
RESUMEN
Metabolic dysfunction-associated steatotic liver disease (MASLD) affects over 30% of the global population, with a significant risk of advancing to liver cirrhosis and hepatocellular carcinoma. The roles of ammonia and glutamine in MASLD's pathogenesis are increasingly recognized, prompting this systematic review. This systematic review was conducted through a meticulous search of literature on December 21, 2023, across five major databases, focusing on studies that addressed the relationship between ammonia or glutamine and MASLD. The quality of the included studies was evaluated using CASP checklists. This study is officially registered in the PROSPERO database (CRD42023495619) and was conducted without external funding or sponsorship. Following PRISMA guidelines, 13 studies were included in this review. The studies were conducted globally, with varying sample sizes and study designs. The appraisal indicated a mainly low bias, confirming the reliability of the evidence. Glutamine's involvement in MASLD emerged as multifaceted, with its metabolic role being critical for liver function and disease progression. Variable expressions of glutamine synthetase and glutaminase enzymes highlight metabolic complexity whereas ammonia's impact through urea cycle dysfunction suggests avenues for therapeutic intervention. However, human clinical trials are lacking. This review emphasizes the necessity of glutamine and ammonia in understanding MASLD and identifies potential therapeutic targets. The current evidence, while robust, points to the need for human studies to corroborate preclinical findings. A personalized approach to treatment, informed by metabolic differences in MASLD patients, is advocated, alongside future large-scale clinical trials for a deeper exploration into these metabolic pathways.