Background: Albuminuria is associated with an increased risk of death independent of level of renal function. Whether this association is similar for adults of all ages is not known.
Methods: We examined the association between the albumin to creatinine ratio (ACR) and all-cause mortality after stratification by estimated glomerular filtration rate (eGFR) and age group in 94 934 veterans with diabetes mellitus. Cohort members had at least 1 ACR recorded in the Veterans Affairs Health Care System between October 1, 2002, and September 30, 2003, and were followed up for death through October 15, 2009.
Results: From the youngest to the oldest age group, the prevalence of an eGFR less than 60 mL/min/1.73 m(2) ranged from 11% to 41%; microalbuminuria (ACR 30-299 mg/g) ranged from 19% to 28%; and macroalbuminuria (ACR > or =300 mg/g) ranged from 3.2% to 3.7%. Of patients with an eGFR less than 60 mL/min/1.73 m(2), 72% of those younger than 65 years, 74% of those 65 to 74 years old, and 59% of those 75 years and older had an eGFR of 45 to 59 mL/min/1.73 m(2). In all age groups, less than 35% of these patients had albuminuria (ie, ACR > or =30 mg/g). In patients 75 years and older, the ACR was independently associated with an increased risk of death at all levels of eGFR after adjusting for potential confounders. In younger age groups, this association was present at higher levels of eGFR but seemed to be attenuated at lower levels [corrected].
Conclusion: The ACR is independently associated with mortality at all levels of eGFR in older adults with diabetes and may be particularly helpful for risk stratification in the large group with moderate reductions in eGFR.