Dietary inflammatory index and pancreatic cancer risk: a systematic review and dose–response meta-analysis

Abstract

AbstractObjective:The meta-analysis was conducted to test the link between pancreatic cancer (PC) risk and dietary inflammatory index (DII®) score.Design:Systematic review and meta-analysis.Setting:We searched PubMed, Embase, Web of Science and the Cochrane Library up to 22 November 2020 to identify the relevant studies. Studies that reported the risk estimates and the corresponding 95 % CI for the DII category and PC risk were included. The effect sizes were pooled using the random-effects model. Dose–response analysis was conducted where possible.Participants:Two prospective cohort studies of 634 705 participants (3152 incident cases), and four case–control studies of 2737 cases and 4861 controls.Results:Overall, the pooled risk ratio (RR) indicated that individuals in the highest category compared with the lowest category had an increased PC risk (RR = 1·45; 95 % CI 1·11, 1·90; P = 0·006). Meanwhile, significant heterogeneity was also revealed. The dose–response meta-analysis indicated that a 1-unit increase in the DII score was associated with the PC risk (RR = 1·08; 95 % CI 1·002, 1·166; P = 0·045; I2 = 94·1 %, P < 0·001). Nonlinear result showed an increased risk of moving from fewer to more inflammatory borders with increasing DII score (Pnonlinearity = 0·003; I2 = 76·5 %, P < 0·001). Subgroup analyses found that significant positive association between PC risk and DII score appeared to be in case–control studies (RR = 1·70; 95 % CI 1·16, 2·50; P = 0·007) and studies with ≤ 31 DII components (RR = 1·76; 95 % CI 1·14, 2·72; P = 0·011).Conclusion:These findings suggested dietary habits with high inflammatory features (high DII score) might increase PC risk.