The association between atherogenic index of plasma and stroke in Chinese middle-aged and elderly population: a national cross-sectional study

Objective: To investigate the association between atherogenic index of plasma (AIP) and stroke. Methods: The 2015 China Health and Retirement Longitudinal Study (CHARLS) survey was used in this study. Logistic regression was adopted to examine the relationship between AIP, calculated as log (TG/HDL), and stroke. Subgroup analysis was used to further explore the associated factors. Restricted cubic spline (RCS) regression was adopted to estimate the non-linear association. Receiver operator characteristic (ROC) analysis was utilized to calculate the cutoff value of AIP. Results: In this study, 13,027 participants aged 45 years above were enrolled. The odds ratios in the fully adjusted logistic model across the quartiles of AIP were 1.00 (reference), 1.09 (95% CI 0.69–1.72), 1.62 (95% CI 1.06–2.49), 1.07 (1.08–2.58), respectively. Non-linear association between AIP and stroke was not found using RCS regression (p for non-linearity > 0.05). The subgroup analyses showed that the association between AIP and stroke varied in different gender, alcohol and cigarette consumption, but the interaction effects were insignificant (all p > 0.05). The cutoff value of AIP was 0.82, and the area under the curve (AUC) was 0.57. Conclusion: Elevated AIP is significantly associated with the increased risk of stroke in the middle- aged and elderly Chinese, indicating that AIP may be a predictive factor for stroke among the Chinese middle-aged and elderly.