HbA1c method performance: The great success story of global standardization

Abstract

Diagnosing and monitoring the treatment of people with diabetes is a global issue and uses considerable resources in laboratories and clinics worldwide. Hemoglobin A1c (HbA1c) has been the mainstay of monitoring glycemic control in people with diabetes for many years and more recently it has been advocated as a diagnostic tool for type 2 diabetes mellitus (T2DM). Good analytical performance is key to the successful use of any laboratory test, but is critical when using the test to diagnose disease, especially when the potential number of diagnoses could exceed 500 million people. Very small variations in bias or increased imprecision could lead to either a missed diagnosis or overdiagnosis of the disease and given the scale of the global disease burden, this could mean erroneous categorization of potentially millions of people. Fundamental to good performance of diagnostic testing is standardization, with defined reference materials and measurement procedures. In this review, we discuss the historical steps to first harmonize HbA1c testing, followed by the global standardization efforts and provide an update on the current situation and future goals for HbA1c testing.

Performance of the Abbott SARS-CoV-2 IgG II Quantitative Antibody Assay Including the New Variants of Concern, VOC 202012/V1 (United Kingdom) and VOC 202012/V2 (South Africa), and First Steps towards Global Harmonization of COVID-19 Antibody Methods

“…Metrological traceability is the property of a measurement result, whereby the result can be related to a reference through a documented unbroken chain of calibrations, each contributing to the measurement uncertainty ( 19 ). While this has been achieved for analytes such as HbA1c, there has been less success with serology testing for viruses such as Rubella virus and, to date, very limited attempts for anti-SARS-CoV-2 antibody methods ( 17 , 21 , 22 ).…”

Addressing shortfalls of laboratory HbA1c using a model that incorporates red cell lifespan

“…The current work aims to extend this model by providing a way to normalise against RBC lifespan variation when individual RBC lifespan becomes available. We propose a new clinical marker, which we term adjusted HbA 1c (aHbA 1c ), by adjusting laboratory HbA 1c for a standard RBC lifespan of 106 days ( English and Lenters-Westra, 2018 ) (equivalent to RBC turnover rate of 0.94% per day). The new glyacemic marker, aHbA 1c , is likely to be the most accurate marker of organ exposure to hyperglycaemia and risk of future diabetes-related complications.…”

The impact of preoperative glycated hemoglobin levels on outcomes in oral squamous cell carcinoma

“…Cancer and DM represent two of the leading causes of mortality globally (Coughlin, Calle, Teras, Petrelli, & Thun, 2004). Diabetic patients have been shown to exhibit higher risks of developing specific cancers, such as liver, pancreatic, colorectal, kidney, bladder, breast, and endometrium (English & Lenters‐Westra, 2018), as well as having poorer cancer outcomes than their non‐diabetic counterparts (American Diabetes, 2018), and various mechanisms have been postulated to explain the association of cancer in diabetic patients and their poorer prognoses (Airley & Mobasheri, 2007; Gallagher & LeRoith, 2010, 2013). Despite the wealth of evidence demonstrating the association of DM and cancer risk, the literature is limited for head and neck cancer.…”

“…Its incidence has increased significantly over the years, predominantly due to changing trends of lifestyle and dietary habits. Furthermore, there is also mounting evidence to suggest that DM is associated with the development of certain cancer types and is associated with poorer cancer prognosis (American Diabetes, 2018; English & Lenters‐Westra, 2018). Specifically for head and neck cancer, the existing literature is however controversial for its association of DM.…”