CKD and cardiovascular disease in screened high-risk volunteer and general populations: the Kidney Early Evaluation Program (KEEP) and National Health and Nutrition Examination Survey (NHANES) 1999-2004.

BACKGROUND: Chronic kidney disease (CKD) is recognized as an independent cardiovascular disease risk state. The relationship between CKD and cardiovascular disease in volunteer and general populations has not been explored.
METHODS: The National Kidney Foundation Kidney Early Evaluation Program (KEEP) is a community-based health-screening program to raise kidney disease awareness and detect CKD for early disease intervention in individuals 18 years or older with diabetes, hypertension, or family history of kidney disease, diabetes, or hypertension. KEEP volunteers completed surveys and underwent blood pressure and laboratory testing. Estimated glomerular filtration rate (eGFR) was computed, and urine albumin-creatinine ratio (ACR) was measured. In KEEP, CKD was defined as eGFR less than 60 mL/min/1.73 m(2) or ACR of 30 mg/g or greater. Cardiovascular disease was defined as self-reported myocardial infarction or stroke. Data were compared with National Health and Nutrition Examination Survey (NHANES) 1999-2004 data for prevalence of cardiovascular disease risk factors and cardiovascular outcomes.
RESULTS: Of 69,244 KEEP participants, mean age was 53.4 +/- 15.7 years, 68.3% were women, 33.0% were African American, and 27.6% had diabetes. Of 17,061 NHANES participants, mean age was 45.1 +/- 0.27 years, 52% were women, 11.2% were African American, and 6.7% had diabetes. In KEEP, 26.8% had CKD, and in NHANES, 15.3%. ACR was the dominant positive screening test for younger age groups, and eGFR, for older age groups, for both populations. Prevalences of myocardial infarction or stroke were 16.5% in KEEP and 15.1% in NHANES (P < 0.001) and 7.8% in KEEP and 3.7% in NHANES (P < 0.001) for individuals with and without CKD, respectively. In adjusted analysis of both KEEP and NHANES data, CKD was associated with a significantly increased risk of prevalent myocardial infarction or stroke (odds ratio, 1.34; 95% confidence interval, 1.25 to 1.43; odds ratio, 1.37; 95% confidence interval, 1.10 to 1.70, respectively). In KEEP, short-term mortality was greater in individuals with CKD (1.52 versus 0.33 events/1,000 patient-years).
CONCLUSIONS: CKD is independently associated with myocardial infarction or stroke in participants in a voluntary screening program and a randomly selected survey population. Heightened concerns regarding risks in volunteers yielded greater cardiovascular disease prevalence in KEEP, which was associated with increased short-term mortality.