Association between Dietary Inflammatory Index and stroke prevalence among American adults: NHANES 2007 to 2016

Limited evidence links chronic inflammation to stroke prevalence, and the Dietary Inflammatory Index (DII) serves as a valid tool to quantify the inflammatory potential of diets. This cross-sectional study utilized data from the National Health and Nutrition Examination Survey 2007 to 2016, enrolling 27,250 adult participants. DII was calculated based on 24 dietary components and categorized into tertiles (Q1: anti-inflammatory diet, Q2: intermediate diet, Q3: pro-inflammatory diet). Stroke status was determined by participants' self-report of physician diagnosis, and covariates included demographic characteristics, socioeconomic status, lifestyle factors, and comorbidities. Weighted logistic regression models and restricted cubic spline analysis were employed to explore the association between DII and stroke. Among the participants, 981 (3.6%) had a history of stroke, with the mean DII significantly higher in stroke patients than in non-stroke patients (mean ± standard deviation: 1.65 ± 1.91 vs 0.96 ± 2.06, P < .001). In the minimally adjusted Model 2, as the DII grouping level increased, the odds of stroke prevalence also increased (odds ratio: 1.80, 95% confidence interval: 1.23, 1.91, P < .001). Restricted cubic spline analysis revealed a linear association between DII and stroke (nonlinear P = .5016), and subgroup analysis indicated significant interactions of this association with age and educational attainment (P < .05). In conclusion, a pro-inflammatory diet is positively associated with stroke prevalence in American adults, with a linear and stable relationship across different subgroups. Optimizing dietary inflammatory potential may be associated with lower stroke prevalence.