Risk of Rapid Kidney Function Decline, All-Cause Mortality, and Major Cardiovascular Events in Nonalbuminuric Chronic Kidney Disease in Type 2 Diabetes

OBJECTIVE We aimed to investigate the rate of progression of nonalbuminuric chronic kidney disease (CKD) to end-stage kidney disease (ESKD) or death or major cardiovascular events (MACE) compared with albuminuric and nonalbuminuric phenotypes. RESEARCH DESIGN AND METHODS We included 10,185 participants with type 2 diabetes enrolled in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study. Based on baseline albuminuria and estimated glomerular filtration rate (eGFR), participants were classified as having no kidney disease (no CKD), albuminuria only (albuminuric non-CKD), reduced eGFR only (nonalbuminuric CKD), or both albuminuria and reduced eGFR (albuminuric CKD). The rate of eGFR decline and hazard ratios (HRs) for ESKD or death or MACE were calculated. RESULTS For individuals with no CKD and those with nonalbuminuric CKD, the rates of eGFR decline were -1.31 and -0.60 mL/min/year, respectively (P < 0.001). In competing-risks analysis (no CKD as the reference), HRs for ESKD indicated no increased risk for nonalbuminuric CKD (0.76 [95% CI 0.34, 1.70]) and greatest risk for albuminuric CKD (4.52 [2.91, 7.01]). In adjusted Cox models, HRs for death and MACE were highest for albumuniuric CKD (2.38 [1.92, 2.90] and 2.37 [1.89, 2.97], respectively) and were higher for albuminuric non-CKD (1.82 [1.59, 2.08] and 1.88 [1.63, 2.16], respectively) than for those with nonalbuminuric CKD (1.42 [1.14, 1.78] and 1.44 [1.13, 1.84], respectively). CONCLUSIONS Those with nonalbuminuric CKD showed a slower rate of decline in eGFR than did any other group; however, these individuals still carry a greater risk for death and MACE than do those with no CKD.