Association of the serum albumin level with prognosis in chronic kidney disease patients

Purpose Chronic kidney disease (CKD) is an important contributor to the overall morbidity and mortality due to noncommunicable diseases. We investigated the relationship between serum albumin and the clinical prognosis in patients with stage G2-G5 CKD who were not undergoing dialysis. Methods This was a post hoc analysis of 1138 patients enrolled from 2010 to 2011 in the Chronic Kidney Disease Research of Outcomes in Treatment and Epidemiology (CKD-ROUTE) study. The primary endpoints were CKD progression, cardiovascular disease (CVD) development, and all-cause mortality. Cox proportional hazards models were used. Results During a median follow-up time of 35 months, the number of patients who experienced CKD progression, CVD development, and all-cause mortality was 278 (24.7%), 116 (10.3%), and 78 (6.9%), respectively. In multivariable-adjusted Cox proportional hazards models, the adjusted hazard ratios (HRs) for CKD progression, CVD development, and all-cause mortality in patients with the highest quartile of serum albumin concentrations compared to those with the lowest quartile of serum albumin concentrations were 0.13 (P < 0.0001), 0.29 (P = 0.0002), and 0.27 (P = 0.0009), respectively, in the model adjusted for demographic factors, hypertension, diabetes, and a history of CVD. After further adjustment for the estimated glomerular filtration rate (eGFR), urinary protein/creatinine ratio (UPCR), and systolic blood pressure (SBP), the results remained significant (HR for CKD progression 0.37, P < 0.0001; HR for CVD development 0.41, P = 0.0120; HR for all-cause mortality 0.37, P = 0.0158). Conclusion Serum albumin levels were inversely associated with the risks of CKD progression, CVD development, and all-cause mortality among patients with stage G2-G5 CKD who were not undergoing dialysis.