Association between atherogenic index of plasma and major adverse cardiovascular events in hypertensive patients at Khok Samrong Hospital: A retrospective cohort study

Abstract

Background: Cardiovascular disease (CVD) remains a leading cause of morbidity and mortality worldwide, particularly among hypertensive individuals. Hypertension is a significant risk factor for major adverse cardiovascular events (MACEs), including myocardial infarction, stroke, and cardiovascular-related mortality. In Thailand, cardiovascular risk assessment tools such as the Thai ASCVD Risk Score are commonly used, incorporating factors such as age, sex, blood pressure, total cholesterol, smoking status, and diabetes history. However, the use of total cholesterol alone may not fully capture the complexity of lipid abnormalities associated with cardiovascular risk. The Atherogenic Index of Plasma (AIP), calculated as log (TG/HDL-C), has gained interest as a potential marker for cardiovascular risk assessment due to its ability to reflect dyslipidemia and arterial stiffness more effectively. Despite its potential utility, data on AIP in Thai hypertensive populations remain limited, and its predictive accuracy may vary across different demographic contexts. Objective: This study aims to evaluate the association between AIP and MACEs in hypertensive patients and to determine the predictive value of AIP for assessing cardiovascular risk. Methods: A retrospective cohort study was conducted using medical records from hypertensive patients treated at Khok Samrong Hospital between January 1, 2014, and January 1, 2025. The study included patients aged 40 years or older with at least one lipid panel test available for AIP calculation and followed for a minimum of one year or until the occurrence of a cardiovascular event. The primary outcome was the incidence of MACEs, including nonfatal myocardial infarction, nonfatal stroke, and cardiovascular-related death. Statistical analysis was performed using Cox proportional hazards regression to assess hazard ratios (HRs). Results: AIP was independently associated with MACEs (HR = 1.97, 95% CI: 1.117-3.490, p = 0.019). Harrell’s C-index improved from 0.58 (AIP alone) to 0.67 when combined with other covariates, indicating enhanced risk stratification. Conclusion: The findings of this study suggest that AIP is a significant independent predictor of MACEs in hypertensive patients. Its integration into cardiovascular risk assessment models could enhance predictive accuracy and help identify high-risk individuals who may benefit from targeted interventions. Given its accessibility and ease of calculation from routine lipid panels, AIP could be a valuable adjunct to existing risk assessment tools. Future prospective studies are warranted to validate these findings and explore the potential of AIP-guided clinical decision-making in hypertensive populations.