CKD prevalence high among people with undiagnosed diabetes, prediabetes

People with undiagnosed diabetes and prediabetes may have chronic kidney disease and not know it, new data suggested.

Researchers analyzed a nationally representative sample of 8,188 adults from the National Health and Nutrition Examination Survey 1999 to 2006. Standard laboratory tests were used to assess the rate of CKD, focusing on people with undiagnosed diabetes or prediabetes. Diabetes status was defined as: no diabetes, fasting plasma glucose <100 mg/dL (n=4,791); diagnosed diabetes, self-reported provider diagnosis (n=826); undiagnosed diabetes, FPG >126 mg/dL without self-reported diagnosis (n=299); or prediabetes, FPG >100 mg/dL and <126 mg/dL (n=2,272).

Based on laboratory tests, 41.7% of people with undiagnosed diabetes had CKD (estimated glomerular filtration rate 15 ml/min per 1.73 m² to 59 ml/min per 1.73 m² or albumin-creatinine ratio >30 mg/g). This was similar to the 39.6% rate of CKD in those with diagnosed diabetes, according to the researchers.

In addition, CKD was present in 17.7% of people with prediabetes.

Among those without diabetes or prediabetes, the rate of CKD was 10.6%.

Further, the age-, sex- and race/ethnicity-adjusted prevalence of CKD was 32.9% for diagnosed diabetes, 24.2% for undiagnosed diabetes, 17.1% for prediabetes and 11.8% for no diabetes.

“Our research indicates that much of the CKD burden in the United States is in persons with prediabetes and undiagnosed diabetes who are not being screened for CKD,” Laura C. Plantinga, ScM, of the University of California, San Francisco, said in a press release. “Only a small percentage of participants were aware of the diagnosis of CKD.”

In an accompanying editorial, Gary C. Curhan, MD, ScD, of Brigham and Women’s Hospital, called for extended CKD screening for patients with prediabetes. Curhan also suggested that it may be time to consider the concept of “pre-CKD” — identifying patients at a very early stage of CKD when the disease may still be preventable or reversible.

Plantinga LC. Clin J Am Soc Nephrol. 2010;5:673-682.