Employment of the Albumin to Alkaline Phosphatase Ratio to Predict All-cause Mortality and Cardiovascular and Cerebrovascular Mortality in Adults Aged At Least 60 Years: An Analysis From NHANES 2003–2018

Background: The relationship between the albumin-to-alkaline phosphatase ratio (AAPR) and all-cause and cardiovascular and cerebrovascular mortalities, in adults aged 60 years and above, remains unclear. Thus, this study aimed to investigate the relationship between the AAPR and all-cause mortality, as well as cardiovascular and cerebrovascular prognosis, in adults aged at least 60 years. Methods: A total of 13,603 eligible participants were included. Kaplan–Meier curves and log-rank tests were utilized to compare variations in all-cause, cardiovascular, and cerebrovascular mortalities across the AAPR quartiles. Multivariate Cox proportional hazards models and restricted cubic splines (RCS) were applied to examine the associations among the AAPR and all-cause, cardiovascular, and cerebrovascular mortalities. Results: Cumulative all-cause mortality and cardiovascular and cerebrovascular mortality in the highest AAPR quartile were remarkably lower than in the lowest quartile. A higher AAPR was related to a diminished risk of all-cause mortality [hazard ratio (HR) = 0.64, 95% confidence interval (CI): 0.57–0.71] and cardiovascular and cerebrovascular mortality (HR = 0.73, 95% CI: 0.60–0.90). The AAPR showed a negative linear association with cardiovascular and cerebrovascular mortality (p for nonlinearity = 0.176). In contrast, the relationship between the AAPR and all-cause mortality followed an L-shaped pattern (p for nonlinearity < 0.001). Conclusions: The AAPR is important in predicting the risks associated with all-cause mortality and cardiovascular and cerebrovascular mortality, providing meaningful insights into mortality risk among the older adult population.