Dose–Response Association of Dietary Inflammatory Potential with All-Cause and Cause-Specific Mortality

Abstract

Although the association of dietary inflammatory potential, evaluated by the dietary inflammatory index (DII), with all-cause and cause-specific mortality has been reported, evidence remains equivocal, with no relevant dose–response meta-analysis having been conducted. To examine the dose–response association of dietary inflammatory potential with risk of all-cause, cancer, and cardiovascular disease (CVD) mortality, PubMed, Embase, and Web of Science were systematically searched up to August 9, 2021. Cohort studies were included if DII was reported as ≥3 levels or per incremental increase, and if the associations of DII with all-cause, cancer, and CVD mortality were assessed. Generalized least squares regression was used to estimate study-specific dose–response associations, and the random effect model was used to pool the RRs and 95% CIs of all-cause, cancer, and CVD mortality per 1-unit increase in DII. Restricted cubic splines were used to intuitively display the dose–response association between dietary inflammatory potential and mortality. Of the 1415 studies retrieved, 15 articles (17 cohort studies involving 397,641 participants) were included in this meta-analysis. With per 1-unit increase in DII, the risks were significantly increased for all-cause mortality (RR: 1.04; 95% CI: 1.03, 1.05, I 2 = 51.8%; P-heterogeneity = 0.009), cancer mortality (RR: 1.02; 95% CI: 1.00, 1.04, I 2 = 58.6%; P-heterogeneity = 0.013), and CVD mortality (RR: 1.04; 95% CI: 1.02, 1.06, I 2 = 85.7%; P-heterogeneity <0.001), respectively. Restricted cubic splines showed significant positive linear associations between DII and the above 3 outcomes. Our study indicated that proinflammatory diets can increase the risk of all-cause, cancer, and CVD mortality in a linear manner