Introduction: Higher intake of ultra-processed foods (UPFs) is linked to cardiometabolic diseases and adverse neurological outcomes, such as stroke and cognitive decline. However, it is controversial whether food processing confers neurological risk independent of nutritive information. We explored associations between UPFs and incident stroke in the longitudinal REasons for Geographic and Racial Differences in Stroke (REGARDS) study. Methods: The NOVA system was used to classify items from a baseline food frequency questionnaire (FFQ) according to level of processing. Intake in grams for each NOVA category was normalized to total grams consumed. Scores quantifying adherence to other diets considered neuroprotective—including a Mediterranean, DASH, and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet—were also derived from FFQ data. Multivariable Cox models were used to evaluate associations between diet patterns and stroke. Results: The cohort included 15,656 participants with reliable dietary intake data and without a previous stroke. Greater intake of UPFs (NOVA4) was associated with increased stroke risk (HR per SD: 1.10, 95% CI [1.03-1.18], p=4.77x10 -3 ) in a model adjusted for demographic factors (age, race, sex, age-by-race interaction) and vascular risk factors (smoking, atrial fibrillation, hypertension, diabetes mellitus, cardiovascular disease, left ventricular hypertrophy). Intake of unprocessed or minimally processed foods (NOVA1) was associated with decreased stroke risk (HR: 0.87, 95% CI [0.81-0.93], p=5.56x10 -5 ) as was adherence to the Mediterranean, DASH, and MIND diets. Adding intake of NOVA1 or NOVA4 items to multivariable models that included other diet patterns resulted in improved model fit (greater log-partial-likelihood). In contrast, adding other dietary patterns to models that included NOVA1 or NOVA4 intake did not improve model fit. While associations between NOVA1 and NOVA4 intake and stroke persisted in models that included the Mediterranean, DASH, or MIND diets, associations between other diet patterns and stroke were not significant. Conclusion: Intake of differentially processed foods is associated with stroke risk independent of adherence to other dietary patterns.
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