Energy-adjusted Dietary Inflammatory Index scores predict long-term cardiovascular disease mortality and other causes of death in an ecological analysis of the Seven Countries Study

Abstract

Using data from the Seven Countries Study of Cardiovascular Diseases, the first study to conduct international comparisons of men in different European, USA, and Japanese cohorts, we examined the effect of diet-associated inflammation on prediction of coronary heart disease-, other major cardiovascular disease- and all-cause mortality after 50-years of follow-up. The energy-adjusted Dietary Inflammatory Index was used to quantify the effect of diet on systemic inflammation. Positive linear correlations were observed between the cohort-average energy-adjusted Dietary Inflammatory Index score and both overall death rates (R = 0.61, p = 0.0114) and major cardiovascular disease mortality rates (R = 0.51, p = 0.0337) but not cancer. Correlations for all-cause mortality were higher when the Belgrade outlier cohort was omitted (R = 0.72, p = 0.0024) or when analyses were adjusted for socioeconomic status (R = 0.67, p = 0.0065). There was also a significant reverse correlation between energy-adjusted Dietary Inflammatory Index score and age at death (R = –0.50 to –0.68, p = 0.0480 to 0.0012). Adjusting for systolic blood pressure, cholesterol, and smoking habits did not modify these correlations that were still significant. With control for these covariates a significant correlation emerged for coronary heart disease. Results obtained using a 25-year follow-up to allow unprojected data from all cohorts were similar. Results from this long-term follow-up study are consistent with a recommendation to increase consuming an anti-inflammatory diet characterized by high concentrations of fruits and vegetables and low consumption of simple carbohydrates and fats.