Association between albumin-to-globulin ratio and long-term mortality in patients with chronic kidney disease: a cohort study

Purpose To examine whether albumin-to-globulin ratio (AGR) is correlated with long-term mortality in patients with chronic kidney disease (CKD), we performed this study using data from the National Health and Nutrition Examination Survey through 1999–2006. Methods 3302 CKD patients were included. Patients’ baseline characteristics were collected. Multivariate Cox proportional hazards models were used to investigate the association between AGR and the study outcomes, including long-term all-cause and cardiovascular mortality. Subgroup analysis using the Cox proportional hazards model was performed as a sensitivity test. Results During a median follow-up duration of 122.00 months, 1627 (49.27%) deaths were recorded and 440 patients died from cardiovascular disease. In adjusted model 1, AGR ≥ 1.26 group was associated with a lower risk of long-term all-cause mortality HR 0.72, 95% CI 0.65–0.81) compared with AGR < 1.26 group. A similar result was obtained in adjusted model 2. In adjusted model 1, AGR ≥ 1.08 group was associated with a lower risk of long-term cardiovascular mortality (HR 0.59, 95% CI 0.45–0.78) compared with AGR < 1.08 group. In adjusted model 2, there was no significant association between AGR ≥ 1.08 group and a decreased risk of long-term cardiovascular mortality (HR 0.82, 95% CI 0.95–1.12) compared with AGR < 1.08 group. The association of AGR with long-term all-cause mortality differed by gender and age while the association of AGR with long-term cardiovascular mortality differed by age after multivariate adjustment. Conclusion AGR is a potential biomarker in risk predictions for long-term mortality in CKD patients, especially in males under age 65.