Association between atherogenic index of plasma and all-cause mortality and cardiovascular disease among individuals with non-alcoholic fatty liver disease or metabolic dysfunction-associated steatotic liver disease.

Background: Non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) are common chronic liver diseases worldwide, both of which are closely associated with an increased risk of cardiovascular disease (CVD). Atherogenic index of plasma (AIP), as a biomarker of dyslipidemia, may predict CVD risk and mortality in these patients, but its specific role in patients with NAFLD and MASLD has not been studied in detail. This study adopted a cohort design, using data from the National Health and Nutrition Examination Survey (NHANES, 1988-1994) database, which was conducted by the Centers for Disease Control and Prevention. A total of 12,929 adult participants were analyzed. After participants were grouped according to AIP quartiles, the relationship between AIP levels and CVD risk was explored using multivariate logistic regression models and restricted cubic splines. The relationship between AIP levels and all-cause and CVD mortality was analyzed using multivariate Cox regression models.

Results: Participants with the higher AIP quartiles showed high rates of CVD among participants with NAFLD (Quartile 1: 7.57%; Quartile 2: 10.00%; Quartile 3: 11.63%; Quartile 4: 15.08%). Participants with the higher AIP quartiles showed high rates of CVD among participants with MASLD (Quartile 1: 9.71%; Quartile 2: 11.30%; Quartile 3: 11.14%; Quartile 4: 15.00%). The findings suggested a linear association between the AIP index and the risk of CVD in participants with NAFLD or MASLD. AIP was significantly associated with CVD in the highest quartile of NAFLD or MASLD patients, and the adjusted hazard ratio indicated that high AIP levels were associated with high risk of CVD among participants with NAFLD (HR: 1.77, 95% CI: 1.24, 2.52) and MASLD (HR 1.76, 95% CI: 1.04, 2.98). In addition, higher AIP levels were also associated with increased all-cause mortality and CVD mortality among participants with NAFLD or MASLD.

Conclusion: This study showed that AIP is an effective tool for predicting CVD risk and mortality in patients with NAFLD and MASLD. Regular monitoring of AIP levels can help identify high-risk patients early and provide clinical risk assessment before intervention, thereby improving patient management and prognosis. Future studies need to further explore the role of AIP in different ethnic and economic conditions to optimize cardiovascular disease prevention and treatment strategies.