The Role of Adipokines in Chronic Pancreatitis. A Systematic Review and Meta-Analysis

Background & Aims: Adipokines are among the biomarkers that have been studied in chronic pancreatitis (CP), as well as in pancreatic cancer (PC). So far, the existing findings are contradictory and inconclusive. Therefore, we assessed the levels of three major adipokines in CP in comparison to controls and PC, adiponectin, leptin, and resistin. Methods: A systematic electronic search was carried out in November 2022 using PubMed, Embase, and Scopus, reviewing observational studies. By using the Newcastle-Ottawa Scale, the included studies' quality was evaluated (NOS). In the examination of the estimated overall effect size, we employed the random-effects model in conjunction with the mean difference (MD) analysis. The MD with 95% confidence interval (CI) served as the primary summary outcome. Results: Our systematic review included a total of 14 studies, out of which nine were considered in our metaanalysis. A significant MD related to leptin levels in CP patients vs. controls (-1.299, 95%CI: -2.493 - -0.105), resistin levels in CP patients vs. controls (8.356, 95%CI: 3.700-13.012), and adiponectin levels in PC patients vs. controls (11.240, 95%CI: 5.872-16.60) was reported. However, no significant MD was reported in leptin levels between CP vs. PC patients (-0.936, 95%CI: -3.325-1.454), as well as adiponectin levels in CP patients vs. controls (0.422. 95%CI -5.651-6.535]) and in CP vs. PC patients (-6.252, 95%CI -13.269-0.766). Conclusions: CP was significantly associated with decreased leptin levels and increased resistin levels. Furthermore, increased levels of adiponectin are associated with PC. Yet, no significant MD was seen for leptin and adiponectin levels between CP and PC patients, and likewise for adiponectin levels between CP patients and controls. Results should be interpreted with caution due to the high heterogeneity between the included studies.