Glycated Albumin and Adverse Clinical Outcomes in Patients With CKD: A Prospective Cohort Study

Abstract

Rationale & ObjectiveHbA1c is widely used to estimate glycemia, yet it is less reliable in patients with chronic kidney disease (CKD). There is growing interest in the complementary use of glycated albumin (GA) to improve glycemic monitoring and risk stratification. However, whether GA associates with clinical outcomes in a non-dialysis dependent CKD population remains unknown. Study DesignProspective cohort study. Setting& Participants: 3110 participants with CKD from the Chronic Renal Insufficiency Cohort study. ExposureBaseline GA levels. OutcomesIncident end-stage kidney disease (ESKD), cardiovascular disease (CVD) events, and all-cause mortality. Analytical ApproachCox proportional hazards regression. ResultsParticipant characteristics included mean age 59.0 (SD 10.8) years; 1357 (43.6%) female; 1550 (49.8%) with diabetes. The median GA was 18.7 (interquartile range, 15.8-23.3)%. During an average 7.9-year follow-up, there were 980 ESKD events, 968 CVD events, and 1084 deaths. Higher GA levels were associated with greater risks of all outcomes, regardless of diabetes status: hazard ratios for ESKD, CVD, and death among participants with the highest quartile compared with quartile 2 (reference) were 1.42 (95%CI, 1.19-1.69), 1.67 (CI, 1.39-2.01), and 1.63 (CI, 1.37-1.94), respectively. The associations with CVD and death appeared J-shaped, with increased risk also seen at the lowest GA levels. Among patients with coexisting CKD and diabetes, the associations of GA with outcomes remained significant even after adjusting for HbA1c. For each outcome, we observed a significant increase in the fraction of new prognostic information when both GA and HbA1c were added to models. LimitationsLack of longitudinal GA measurements; HbA1c measurements were largely unavailable in participants without diabetes. ConclusionsAmong patients with CKD, GA levels were independently associated with risks of ESKD, CVD, and mortality, regardless of diabetes status. GA added prognostic value to HbA1c among patients with coexisting CKD and diabetes.