Dietary Anti-Oxidant Capacity, Dietary Inflammation Index, and the Risk of Stroke in a Large Prospective Cohort Study.

Abstract BackgroundWhilst the Western and Mediterranean/prudent diets have long been associated with the risk of stroke, it is less clear if increased inflammation and reduction of oxidations are their respective mechanisms. This study aimed to understand the associations between the dietary inflammatory index (DII), and total anti-oxidant capacity of the diet (TAC), with regards to stroke risk.MethodsThe study population included 71,460 women free of cardiovascular disease at baseline from the E3N cohort, who completed a diet history questionnaire which was used to estimate the dietary pattern scores. Scores were considered grouped as quintiles and as splines in order to determine the dose-response shape. Hazard ratios (HRs) and 95% confidence intervals (95% CI) for hypertension were estimated with multivariate Cox models with age as the time scale, and adjusted for potential confounding factors. After Bonferroni correction, a p-value of 0.013 was considered significant.ResultsOver 14.5 years of follow-up, 414 cases of incident stroke were identified. The Western, and Prudent dietary patterns were both highly associated with the risk of stroke (Western HRQ1Q4 = 1.85 [1.27: 2.69], p-trend = 0.002, Prudent HRQ1Q4 = 0.59 [0.44: 0.78], p-trend < 0.001), as was TAC from non-coffee sources (HRQ1Q4 = 0.47 [0.33: 0.68], p-trend < 0.001). All three showed a clear dose-response, and the associations with the Western and Prudent scores were consistent in sensitivity analysis. Weaker evidence was observed for DII (HRQ1Q4 = 1.33 [1.01: 1.78], p-trend = 0.03), which did not show a clear dose-response. TAC from coffee was not associated with the risk of stroke.ConclusionThese results suggest that diets high in anti-oxidants are associated with a reduced risk of stroke, but that inflammation from the diet does not play as large a part in the risk of stroke. Factors other than inflammation may be driving associations with stroke and western diet.