African Americans experience faster progression of CKD during later stages

Among individuals with chronic kidney disease (CKD), African Americans experience faster progression of the disease during later stages compared with other races, according to a study appearing in an upcoming issue of the Journal of the American Society of Nephrology (JASN). Also, screening of African Americans with CKD can help improve care and is cost-effective.

It is well known that African Americans have a similar prevalence of CKD as other Americans, but they are more likely to progress to kidney failure. The lifetime incidence of kidney failure is about 8.6% for African Americans compared with 3.5% for other Americans. The reasons for this disparity are not known.

To investigate, Thomas Hoerger, PhD (RTI International) and his colleagues used a simulation model of CKD progression to see if the prevalence of common CKD risk factors (such as high blood pressure and diabetes) could explain the higher lifetime incidence of kidney failure among African Americans.

The researchers found that the higher lifetime incidence of kidney failure among African Americans was not fully explained by the prevalence of common CKD risk factors. Instead, it could be explained by faster progression of CKD among African Americans during the later stages of the disease.

The investigators then considered whether screening for a particular marker of CKD called microalbuminuria—when the kidneys leak small amounts of protein into the urine—would be cost-effective. (Screening could lead to earlier treatment that might prevent kidney failure.) "We found that screening for microalbuminuria is cost-effective for African Americans at either five- or 10-year intervals, particularly for those with diabetes or hypertension," said Dr. Hoerger.

Kidney failure affected more than 571,000 US adults and cost more than $42 billion in 2009.