Glycosylated Hemoglobin Test Helps Detect Subclinical Atherosclerosis

A routine lab test for glycosylated hemoglobin to track blood sugar levels was also able to identify individuals at elevated risk for more advanced atherosclerotic disease, new study results suggest.

“The metabolic injury caused by protein glycation, monitored as the level of glycated hemoglobin (HbA1c), is not represented in most risk scores (i.e., Systematic Coronary Risk Estimation or atherosclerotic cardiovascular disease risk scale),” the authors wrote in their study, published in the Journal of the American College of Cardiology. “The purpose of this study was to assess the association between HbA1c and the extent of subclinical atherosclerosis and to better identify individuals at higher risk of extensive SA using HbA1c on top of key cardiovascular risk factors (CVRFs).”

The authors enrolled 3,973 participants in the Progression of Early Subclinical Atherosclerosis (PESA) with no history of cardiovascular disease and HbA1c within a nondiabetic range. The team assessed the individuals for the presence and extent of subclinical atherosclerosis via 2-dimensional vascular ultrasound and noncontrast cardiac CT. Participants were also put into different categories of HbA1c to explore associations. The authors used a SCORE risk algorithm that predicts 10-year risk of cardiovascular death. They then used univariate and multivariate regression models to assess associations, and calculated predicted probabilities using the SCORE algorithm.

According to the results, HbA1c showed an association with all territories of subclinical atherosclerosis (P<0.001 for all associations). The association was significant in all pre-diabetes subgroups and below the pre-diabetes cutoff. In low-risk individuals, high HbA1c levels were associated with an increased risk for subclinical atherosclerosis (P<0.001), but not in moderate-risk individuals. The inclusion of HbAic in relative risk estimations, whether they be Systematic Coronary Risk Estimation or atherosclerotic cardiovascular disease predictors, modified the risk of multiterritorial subclinical atherosclerosis across most risk categories.

Subclinical Atherosclerosis in 1 in 5 at Low-risk

“The key finding of the present study is that subclinical atherosclerosis is prevalent in the 21.2% of the study population with HbA1c in the band below the pre-diabetes cut-off, and therefore considered not to be at risk,” the authors wrote in the study.

The limitations included a lack of a causal relationship between HbA1c and subclinical atherosclerosis. Others included residual confounding variables, and a lack of application to a general population dur to the homogenous study cohort.

“The glycosylated hemoglobin test was especially useful in identifying subclinical disease in participants classified at low risk according to traditional scores; it made less of a contribution to risk calculation for individuals who already had a moderate level risk according to other risk factors,” Dr. Xavier Rosselló, study researcher, CNIC scientist, and cardiologist at Hospital Universitario Son Espases in Palma de Mallorca, said in a news release. “This study establishes glycosylated hemoglobin as a mass-use biomarker because its greatest benefit is in individuals at low cardiovascular risk, who form the immense majority of the general population and account for most cardiovascular deaths in absolute terms.”