Atherogenic index predicts all-cause and cardiovascular mortality in incident peritoneal dialysis patients

Background and aims: Atherosclerosis, the main cause of cardiovascular disease (CVD), is prevalent in patients undergoing peritoneal dialysis (PD). Atherogenic index (AI) is a strong predictor of atherosclerosis. However, its prognostic value in CVD outcomes and all-cause mortality among patients undergoing PD remains uncertain. Therefore, we aimed to evaluate the association between AI and all-cause and CVD mortality in PD patients. Methods: Calculated based on lipid profiles obtained through standard laboratory procedures, AI was evaluated in 2682 patients who underwent PD therapy between January 2006 and December 2017 and were followed up until December 2018. The study population was divided into four groups according to the quartile distribution of AI (Q1: <2.20, Q2: 2.20 to <2.97, Q3: 2.97 to <4.04, and Q4: >=;4.04). Multivariable Cox models were employed to explore the associations between AI and CVD and all-cause mortality was evaluated. Results: During a median follow-up of 35.5 months (interquartile range, 20.9-57.2 months), 800 patients died, including 416 deaths from CVD. Restricted cubic splines showed non-linear relationship between AI and adverse clinical outcomes. The risks of all-cause and CVD mortality gradually increased across quartiles (log-rank, p < 0.001). After adjusting for potential confounders, the highest quartile (Q4) showed significantly elevated hazard ratio (HR) for both all-cause mortality (HR 1.54 [95% confidence interval (CI), 1.21-1.96]) and CVD mortality risk (HR 1.78 [95% CI, 1.26-2.52]), compared to the lowest quartile (Q1). Conclusions: AI was independently associated with all-cause and CVD mortality in patients undergoing PD, suggesting that AI might be a useful prognostic marker.