HbA1c testing reveals subgroup of patients at increased CV death risk
MedWire News: The latest American Diabetes Association (ADA) definition of diabetes, including elevated glycated hemoglobin (HbA1c) levels, may lead to improved cardiovascular (CV) risk stratification, report researchers.
The previous ADA guidelines from 2009 recommended that a diagnosis of diabetes should be made in individuals with increased fasting glucose (≥126 mg/dl) and/or postchallenge glucose of 200 mg/dl or more.
However, the broader ADA 2010 criteria advise that a diagnosis of diabetes is also made for patients who have normal fasting and postchallenge glucose levels but elevated HbA1c levels, at 6.5% or higher.
As reported in the journal Diabetes Care, Winfried März (University of Heidelberg, Mannheim, Germany) and team analyzed data from 2002 individuals, with no previous history of diabetes, who participated in the Ludwigshafen Risk and Cardiovascular Health (LURIC) study, between 1997 and 2000, and who underwent coronary angiography.
They compared participants' clinical and biochemical baseline characteristics with data on mortality that was gathered over a follow-up period of 7.7 years.
The authors found that, in total, 1384 of the patients met the criteria for diabetes as per the ADA 2010 definition.
They also found that people with Type 2 diabetes as per the ADA 2010 definition but without diabetes according to the ADA 2009 definition (n=150) were at increased risk for CV mortality relative to those without diabetes, at a hazard ratio of 1.98.
Importantly, this meant they were at a similarly increased CV mortality risk as those diagnosed with diabetes as per the ADA 2009 criteria (n=468; HR=1.99), the authors say.
The researchers conclude that the use of HbA1c at a cut point of 6.5% or more as an additional criterion for the diagnosis of diabetes may improve CV risk stratification in patients referred for coronary angiography.
"Future studies should attempt to answer the question of whether measurement of glycated hemoglobin will obviate the need for oral glucose tolerance testing," write März and team.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Sally Robertson