Increasing Mortality in Adults With Diabetes and Low Estimated Glomerular Filtration Rate in the Absence of Albuminuria

OBJECTIVE Improved blood pressure control and use of renin-angiotensin-aldosterone system blockers have altered the clinical presentation or phenotype of chronic kidney disease (CKD) in U.S. adults with diabetes. These changes may influence mortality. RESEARCH DESIGN AND METHODS Data from the National Health and Nutrition Examination Surveys (NHANES) 1988–2006 were used to examine mortality trends in adults with diabetes, defined as physician diagnosis, fasting glucose ≥126 mg/dL, HbA1c >6.5% (48 mmol/mol), or use of glucose-lowering medications. Mortality trends by CKD phenotype (estimated glomerular filtration rate [eGFR] and urine albumin-to-creatinine ratio [ACR] level) were obtained via linkage with the National Death Index through 31 December 2011 while accounting for the complex survey design. RESULTS From 1988 to 2006, adults with an eGFR <60 mL/min/1.73 m2 and an ACR <30 mg/g increased from ∼0.9 million (95% CI 0.7, 1.1) or 6.6% of the total population with diabetes during years 1988–1994 to 2.4 million (95% CI 1.9, 2.9) or 10.1% of the total population with diabetes during years 2007–2010. Mortality rates generally trended downward for adults with diabetes and an ACR ≥30 mg/g but increased in those with eGFR <60 mL/min/1.73 m2 and an ACR <30 mg/g from 35 deaths per 1,000 person-years (95% CI 22, 55) during years 1988–1994 to 51 deaths per 1,000 person-years (95% CI 33, 83) during years 2003–2006. CONCLUSIONS ACR values are decreasing in U.S. adults with diabetes, but optimal management strategies are needed to reduce mortality in those with a low eGFR and an ACR <30 mg/g.