Bidirectional association between non-alcoholic fatty liver disease and fatty pancreas: a systematic review and meta-analysis

Abstract

BACKGROUND: Accumulating evidence suggests a potential relationship between non-alcoholic fatty liver disease (NAFLD) and fatty pancreas, as both conditions are associated with fat deposition in the liver and pancreas, respectively. The meta-analysis aimed to investigate the bidirectional association between NAFLD and fatty pancreas, as well as their respective effects on disease severity. METHODS: A systematic search of the EMBASE and MEDLINE databases, from inception to August 2022, was conducted to identify observational studies examining the association between NAFLD and fatty pancreas, as well as their impact on disease severity. The pooled odds ratio (OR) with a 95% confidence interval (CI) was estimated using a random-effects model. RESULTS: Our analysis included 26 case-control or cross-sectional studies, comprising 67,803 participants. We observed a significant association between NAFLD and an increased odds of having fatty pancreas (OR, 6.18; 95% CI, 4.49-8.51; I2 = 92%). Similarly, fatty pancreas was significantly associated with an increased odds of having NAFLD (OR, 9.56; 95% CI, 5.09-17.95; I2 = 83%). Furthermore, the presence of fatty pancreas was associated with a 1.75-fold increased risk of severe NAFLD based on ultrasonographic classification (95% CI, 1.46-2.10; I2 = 0%). Among NAFLD patients, the coexistence of fatty pancreas was associated with a trend towards increased odds of having non-alcoholic steatohepatitis (OR, 3.52; 95% CI, 0.65-18.93; I2 = 82%) and advanced fibrosis (OR, 2.47; 95% CI, 0.52-11.80; I2 = 76%). CONCLUSION: This meta-analysis discloses a bidirectional association between NAFLD and fatty pancreas, emphasizing the importance of understanding the intricate relationship between these two conditions.