CKD in the United States: Kidney Early Evaluation Program (KEEP) and National Health and Nutrition Examination Survey (NHANES) 1999-2004
Received 7 November 2007; accepted 31 December 2007.
Background
The prevalence of chronic kidney disease (CKD) is increasing in the United States, caused in part by older age and increasing prevalences of hypertension and type 2 diabetes. CKD is silent and undetected until advanced stages. The study of populations with earlier stages of kidney disease may improve outcomes of CKD.
Methods
The Kidney Early Evaluation Program (KEEP), a National Kidney Foundation program, is a targeted community-based health-screening program enrolling individuals 18 years and older with diabetes, hypertension, or family history of kidney disease, diabetes, or hypertension. Participants who had received transplants or were on regular dialysis treatment were excluded from this analysis. The National Health and Nutrition Examination Survey (NHANES) 1999-2004 was a nationally representative cross-sectional survey; participants were interviewed in their homes and/or received standardized medical examinations in mobile examination centers.
Results
Of the 61,675 KEEP participants, 16,689 (27.1%) were found to have CKD. In the NHANES sample of 14,632 participants, 2,734 (15.3%) had CKD. Older age, smoking, obesity, diabetes, hypertension, and cardiovascular disease were associated significantly with CKD in both KEEP and NHANES (P < 0.05 for all). Of note, the likelihood for CKD in African Americans differed between KEEP (odds ratio, 0.81; P < 0.001) and NHANES (odds ratio, 1.10; P = 0.2).
Conclusion
A greater prevalence of CKD was detected in the KEEP screening than in the NHANES data. KEEP has the limitations common to population-screening studies and conclusions for population-attributable risk may be limited. The targeted nature of the KEEP screening program and the large sample size with clinical characteristics comparable to NHANES validates KEEP as a valuable cohort to explore health associations for the CKD and at-risk-for-CKD populations in the United States.
4Veterans Association Medical Center, San Francisco, CA
5Charles R. Drew University of Medicine and Science, Los Angeles, CA
6David Geffen School of Medicine, University of California, Los Angeles, CA
7Chronic Disease Research Group, Minneapolis Medical Research Foundation, Minneapolis, MN
8National Kidney Foundation and Department of Medicine, Division of Nephrology, Mount Sinai School of Medicine, New York, NY.
Address correspondence to Adam T. Whaley-Connell, DO, MSPH, Assistant Professor of Medicine, University of Missouri-Columbia School of Medicine, Department of Internal Medicine, Division of Nephrology, MA436, DC043.0, One Hospital Dr, Columbia, MO 65212.
A list of the members of the Kidney Early Evaluation Program Investigators appears at the end of this article.
ABSTRACT