Dietary Inflammatory Index Is Associated with Risk of All-Cause and Cardiovascular Disease Mortality but Not with Cancer Mortality in Middle-Aged and Older Japanese Adults

Abstract

Background The Dietary Inflammatory Index (DII) is a comprehensive, literature-derived index for assessing the effect of dietary constituents on inflammatory biomarkers. Several studies have shown an association between DII score and mortality, but there are limited prospective studies in Asian populations. Objectives The aim of this study was to investigate the association between DII score and risk of all-cause, total cardiovascular disease (CVD), stroke, coronary heart disease (CHD), total cancer, digestive cancer, and noncancer/non-CVD mortality in the Japanese population. Methods A total of 58,782 Japanese participants aged 40–79 y who were enrolled in the Japan Collaborative Cohort Study during 1988–1990 were included in the analysis. DII scores were calculated based on a food-frequency questionnaire. HRs and 95% CIs for mortality according to DII quintiles were estimated using Cox proportional hazards models. Results During the median follow-up period of 19.3 y, a total of 11,693 participants died. The multivariable HR for all-cause mortality for the highest compared with the lowest DII quintiles was 1.13 (95% CI: 1.05, 1.21). For CVD mortality, the highest multivariable HRs were 1.30 (95% CI: 1.13, 1.49), 1.29 (95% CI: 1.05, 1.59), and 1.30 (95% CI: 0.96, 1.76) for total CVD, stroke, and CHD, respectively. No significant associations were observed between DII and risk of total cancer, digestive cancer, and noncancer/non-CVD mortality. Conclusion Our findings suggest that a higher DII was associated with an increased risk of all-cause and CVD mortality among Japanese adults.

Association of dietary inflammatory potential with risk of overall and cause-specific mortality

“…DII score has been validated to significantly predict inflammation markers in several populations (37)(38)(39) . In line with the current observations, previous DII studies (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26) consistently showed that higher inflammatory potential of diets was associated with elevated risk of overall and some cause-specific mortality. Nonetheless, findings from DII studies on health outcomes are difficult to be translated readily into public health interventions, given that DII comprises mainly of nutrients.…”

Positive Association of Dietary Inflammatory Index with Incidence of Cardiovascular Disease: Findings from a Korean Population-Based Prospective Study

“…For example, Asadi et al [26] recently reported the association between DII and CVD and its subtypes, MI, stable angina, and unstable angina risk in northeastern Iran; however, the incidence rate was very low and regionally specific, which makes it difficult to generalize the results to the entire Iranian population, let alone outside of Iran. Another Asian study from Japan reported the association between the DII and overall CVD and stroke mortality among other diseases, but failed to address the disease incidence risk [29]. However, to our knowledge, no previous study has been conducted to examine the association between the DII and incidence of CVD in an East-Asian population whose dietary habits are different from those of the other populations studied.…”

“…Therefore, because of the possible selection bias, these results might not be simply generalized to a population outside Europe. Moreover, the broader application of this approach to non-Western populations is also limited, as indicated by the relative lack of studies conducted in Asian populations that have addressed the association between the DII and CVD risk [26,28,29]. For example, Asadi et al [26] recently reported the association between DII and CVD and its subtypes, MI, stable angina, and unstable angina risk in northeastern Iran; however, the incidence rate was very low and regionally specific, which makes it difficult to generalize the results to the entire Iranian population, let alone outside of Iran.…”

Dietary Inflammatory Index and Non-Communicable Disease Risk: A Narrative Review

“…However, it should be noted that the number of studies for these subgroup analyses are low, and thus the results should be interpreted with caution. Studies published after these reviews also reported significant direct association between DII score and CVD risk (estimated from Framingham Risk Score) [172] and CVD mortality [9,173]. Nonetheless, subgroup analysis in our meta-analysis [11] also suggested that the association between DII and CVD risk or mortality is likely independent from the influence of BMI and lifestyle factors such as smoking and physical activity, as the pooled estimates remained statistically significant in studies that adjusted for these factors.…”