Glycated Albumin (GA) and HbA1c Comparison Supports Utility of GA Test
February 6, 2017
Clinical Chemistry and Laboratory Medicine (CCLM) recently published an analysis of hemoglobin A1c (HbA1c) and glycated albumin (GA) as effective glycemic markers. This study, led by Dr. Roberto Testa, MD of INRCA-IRCCS National Institute concluded that GA% (GA on total albumin ratio) is a useful indicator for diabetes management and monitoring where HbA1c is limited.
As summarized in the article, several past studies support the potential for GA to be an overall marker for diabetes. For example, GA% is found to be useful when “HbA1c loses reliability…in anemic, hemoglobinopathic, and kidney disease” patients and “as a diabetes screening index in blood donors.” Moreover, a Chinese study revealed that combining GA with fasting plasma glucose (FPG) “increases diabetes detection and reduce[s] resorting to the oral glucose tolerance test (OGTT).”
Another study that assayed GA% on three analytical platforms conducted at San Raffaele Hospital laboratory found a good correlation of GA% vs. HbA1c. This report concludes that the high correlation found between GA% and HbA1c clearly confirms that glycated albumin is as good an indicator of protein glycation as HbA1c and that GA% is directly dependent on protein exposure to glucose.”
The article also recommends further investigation of GA's “usefulness in diabetes diagnosis or diabetic patient follow-up” because of its unique capability “to assess glycation exposure in a shorter time frame.” This supports the FDA’s recent efforts to highlight diabetes outcome measures beyond HbA1c including a public workshop this past August to fuel a discussion about novel therapies for patients with diabetes. According to the article, further research in “different scenarios can confirm the value of GA% as a stand-alone test or in combination with FPG and HBA1c as an added information in patient screening or staging.”