Department of Cancer Research and Molecular Medicine, Faculty of Medicine, NTNU St Olav University Hospital, Olav Kyrres gt 17, Trondheim, Norway. stein.hallan@ntnu.no
BACKGROUND: The cardiovascular risk implications of a combined assessment of reduced kidney function and microalbuminuria are unknown. In elderly persons, traditional cardiovascular risk factors are less predictive, and measures of end organ damage, such as kidney disease, may be needed for improved cardiovascular mortality risk stratification. METHODS: The glomerular filtration rate was estimated from calibrated serum creatinine, and the urine albumin-creatinine ratio (ACR) was measured in 3 urine samples in 9,709 participants of the second Nord-Tr?ndelag Health Study (HUNT II), a Norwegian community-based health study, followed for 8.3 years with a 71% participation rate. RESULTS: An estimated glomerular filtration rate (EGFR) at levels of less than 75 mL/min/1.73 m(2) was associated with higher cardiovascular mortality risk, whereas a higher ACR was associated with higher risk with no lower limit. Low EGFR and albuminuria were synergistic cardiovascular mortality risk factors. Compared with subjects with an EGFR greater than 75 mL/min/1.73 m(2) and ACR below the sex-specific median who were at the lowest risk, subjects with an EGFR of less than 45 mL/min/1.73 m(2) and microalbuminuria had an adjusted incidence rate ratio of 6.7 (95% confidence interval, 3.0-15.1; P