Association between dietary inflammatory index with all-cause and cardiovascular disease mortality among older US adults: A longitudinal cohort study among a nationally representative sample

To investigate the association between DII with all-cause and cardiovascular disease (CVD) mortality among older adults in the U.S This prospective cohort study included older adults with complete DII data and mortality data from the National Health and Nutrition Examination Survey (NHANES) 2001–2018. Mortality outcomes were linked to National Death Index records through 31 December 2019. The multivariate Cox proportional hazards models were performed to evaluate the association between DII and mortality. Restricted cubic spline analyses were used to examine the nonlinear association of DII with all-cause and CVD mortality. During the median follow-up date of 6.7 years, 4446 all-cause deaths were documented among 10,827 representative older adults, including 1230 CVD deaths. After multivariate adjustment, linear relationships between DII with all-cause mortality (P non-linear = 0.17) and non-linear relationship between DII with CVD mortality (P non-linear = 0.04) were observed. Compared to participants with the lowest quartile of DII scores (-5.28 to≤0.43), the multivariate-adjusted HRs and 95 %CI for participants with higher DII scores were 1.19 (Q2, 95 %CI: 1.08–1.31), 1.28 (Q3, 95 %CI: 1.14–1.44), 1.30 (Q4, 95 %CI: 1.17–1.44) for all-cause mortality (P trend <0.001) and 1.19 (Q2, 95 %CI: 0.99–1.43), 1.34 (Q3, 95 %CI: 1.10–1.62), 1.30 (Q4, 95 %CI: 1.06–1.58) for CVD mortality (P trend < 0.01), respectively. In the representative sample of older adults in the U.S, higher DII scores were associated with increased risks of all-cause and CVD mortality.