Abstract / Summary
Abstract Background The Dietary Inflammatory Index (DII) summarizes the inflammatory potential of habitual diet, but evidence linking pre-stroke dietary inflammatory potential to neurological injury and recovery after acute ischemic stroke (AIS) remains limited. Methods We retrospectively analyzed a consecutively enrolled single-center observational cohort of patients with AIS recruited from June 1, 2024 through May 2025. Habitual diet during the year before stroke was assessed using a semi-quantitative food-frequency questionnaire, and a literature-derived DII was calculated from 30 available non-energy dietary parameters. The primary outcome was unfavorable functional outcome approximately 90 days after hospital admission (modified Rankin Scale [mRS] 2–6 vs 0–1; permitted assessment window 90 ± 7 days after hospital admission); the secondary outcome was admission National Institutes of Health Stroke Scale (NIHSS) > 3. Multivariable logistic regression, restricted cubic splines, and sensitivity analyses were performed. Results Among 303 patients, 106 (35.0%) had a 90-day unfavorable functional outcome and 112 (37.0%) had admission NIHSS > 3. In 299 complete cases, each 1-SD higher DII was associated with greater odds of the 90-day outcome after adjustment for demographic factors, vascular risk factors, and reperfusion therapy (OR 1.70, 95% CI 1.29–2.25; P < 0.001), and the association remained after additional adjustment for admission NIHSS (OR 1.59, 95% CI 1.20–2.11; P = 0.001). The adjusted OR for admission NIHSS > 3 was 1.34 (95% CI 1.04–1.74; P = 0.026) per 1-SD higher DII. The alternative mRS 3–6 endpoint and restriction to first-ever stroke supported the primary association. The 90-day spline model supported an overall association without establishing statistically significant nonlinearity. Conclusions Higher pre-stroke dietary inflammatory potential was associated with greater neurological deficit at admission and worse 90-day functional outcome after AIS. These observational findings require confirmation in larger, multicenter cohorts with standardized dietary assessment, prospectively retained energy and anthropometric data, and broader representation of stroke severity.