Association between the dietary inflammatory index and all-cause and cardiovascular mortality in patients with atherosclerotic cardiovascular disease

Abstract

Background and aimsAtherosclerotic cardiovascular disease (ASCVD) is the leading cause of death worldwide. Inflammation is pivotal in atherosclerosis development. The dietary inflammatory index (DII) is a tool to quantify the overall inflammatory potential of diet. The association between DII and all-cause and cardiovascular mortality in ASCVD patients remains undetermined. Methods and resultsParticipants included individuals with ASCVD from the National Health and Nutrition Examination Survey from 1999 to 2018. A total of 5006 participants were included, during a median of 6.6 years of follow-up, of which 2220 (44.4 %) were dead. The Cox proportional hazard model evaluated the association between DII and all-cause and cardiovascular mortality. Participants in the higher DII quartile exhibited a higher mortality of ASCVD. Compared with the patients in quartile 1, those in quartile 4 had a 34 % increased risk for all-cause mortality (HR = 1.34, 95 % CI = 1.21–1.61, p = 0.001). Cardiovascular mortality showed a similar trend, however the correlation is not significant. The restricted cubic spline (RCS) showed that the relationship between DII and all-cause and cardiovascular mortality was linear. Subgroup analysis revealed a persistently positive association between DII and all-causemortality across population subgroups. However, an interaction was detected between DII and alcohol history in relation to cardiovascular mortality. ConclusionDII was positively correlated with the all-cause mortality of ASCVD patients. The intake of a pro-inflammatory diet may increase mortality in ASCVD patients.