Atherosclerosis index and BMI: new predictors of cognitive function in ischemic survivors.

Background: The atherogenic index of plasma (AIP) is a reliable surrogate marker for insulin resistance and is strongly associated with both stroke risk and prognosis. However, the associations of AIP and the composite index AIP-BMI with cognitive function among patients with ischemic stroke remain insufficiently studied. Methods: This cross-sectional study included 2,933 patients with ischemic stroke. Demographic and clinical data were collected from all participants. The AIP was calculated as log [TG (mmol/L)/HDL-C (mmol/L)], and cognitive function was evaluated using the Mini-Mental State Examination (MMSE). Multivariable linear regression models were applied to examine the associations between AIP (and AIP-BMI) and MMSE scores, adjusting for potential confounders. Stratified and sensitivity analyses were further conducted to evaluate the robustness of the findings. Results: The mean age of participants was 64.8 years (SD 10.2), and 2,009 (68.5%) were male. Each one-unit increase in AIP was associated with a 1.15-point reduction in MMSE score (p < 0.001). Similarly, each one-unit increase in AIP-BMI corresponded to a 0.04-point decrease in MMSE score (p < 0.001). The inverse associations remained consistent when AIP and AIP-BMI were analyzed by tertiles. Conclusion: Higher levels of AIP and AIP-BMI are independently associated with poorer cognitive performance in patients with ischemic stroke. These findings suggest that dyslipidemia-related metabolic disturbances may contribute to post-stroke cognitive impairment. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=120858, identifier ChiCTR2100042721.