GA Assay Better for Monitoring Diabetic Kidney Patients

The glycated albumin (GA) assay appears to be far more effective than the hemoglobin A1c (HbA1c) for managing patients with diabetes and advanced kidney failure.

A study evaluated 444 patients with diabetes undergoing dialysis. Patients continued their normal treatment and HbA1c monitoring, but also agreed to have a GA test every three months for an average of more than 2.3 years.

Barry I. Freedman, MD, John H. Felts III Professor at the Wake Forest Baptist Medical Center (Winston-Salem, NC, USA) and colleagues compared the patients' HbA1c and GA test results, assessing their ability to predict hospitalizations and survival. They found that the HbA1c failed to predict medical outcomes. In contrast, the GA was a strong predictor of patient survival and hospitalizations.

The GA test, developed by Asahi Kasei Pharma Corp. (Tokyo, Japan), measures blood sugars over the past 17 days, as opposed to the longer time frame for HbA1c. In situations where rapid changes occur in blood sugar, the GA gives a more accurate picture of diabetes control. The GA test used in this study is available in Japan, China, and South Korea, but is not yet approved by the US Food and Drug Administration (FDA; Silver Spring, MD, USA).

The gold standard long-term glucose-monitoring test for patients with diabetes is the HbA1c test. It measures an individual's average blood sugar level over the prior three months. It is the most commonly used long-term blood sugar test, and is widely trusted in the medical community.

However, HbA1c results are only accurate when red cells have a normal lifespan. Dialysis patients have shorter red cell survival-- reducing the time that sugar in the bloodstream has to interact with hemoglobin, and causing lower HbA1c values.

The study appeared online in the May 19, 2011 edition of Clinical Journal of the American Society of Nephrology.

Related Links:
Wake Forest Baptist Medical Center
Asahi Kasei Pharma Corp.
US Food and Drug Administration