A Threshold for Prediabetes Treatment

HbA1c cutoff marker makes prediabetes treatment beneficial and cost effective

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Stopping diabetes before it starts is the key to lowering rates of this common disease. The question is: when is the best time to step in with medical treatment without wasting precious resources?

A team of researchers at the Centers for Disease Control and Prevention (CDC) recommends that medical treatment for people with prediabetes (blood sugar levels that are higher than normal but not high enough to be called diabetes) should begin when their HbA1c levels (a measure of blood sugar over time) reach 5.7 percent or higher.

This threshold may provide the most health benefits while still being cost-effective.

"Eat healthy and get exercise to prevent diabetes."

Having an HbA1c cutoff marker for prediabetes would help doctors decide when it is best to start medical treatment in order to stop the progression to the more serious type 2 diabetes. However, there has been much debate about where to set that cutoff marker.

Currently, there are at least three different cutoff markers recommended by three different groups.

With this disagreement in mind, Xiaohui Zhuo, Ph.D., of the Division of Diabetes Translation at the CDC, and colleagues tested the impact and cost effectiveness of different HbA1c cutoff markers for prediabetes.

According to Dr. Zhuo, large-scale diabetes prevention strategies depend on an effective method for spotting people who have a high risk of type 2 diabetes. Knowing who is at high risk helps doctors determine who needs to be treated.

"This is the first study to examine the population-level impact and cost effectiveness of using alternative HbA1 cutoffs to determine eligibility for type 2 diabetes preventive interventions," explains Dr. Zhuo.

For their study, the researchers used a simulation model to look at the cost effectiveness of different HbA1c cutoffs, from 5.5 percent to 6.4 percent. The simulation data came from non-diabetic adults who participated in the National Health and Nutritional Examination Survey between 1999 and 2006.

If a person was determined to have prediabetes, it was assumed that he or she received one of two interventions: a low-cost intervention of $300 per year or a high-cost intervention of $1,000 per year.

The researchers calculated the cost per each quality-adjusted life year (a measure of the quality and length of life resulting from a medical intervention) at each HbA1c cutoff marker for both interventions.

They found that a cutoff of 5.7 percent was the most cost-effective. Their findings also suggest that the cutoff point could be even less if the cost of the interventions could be lowered without reducing their effectiveness.

Dr. Zhuo believes that we need to gain a full understanding of the economic effects of using HbA1c levels to spot people at high risk of type 2 diabetes, especially as the use of HbA1c tests is likely to increase.

"This study will hopefully stimulate more research on the best strategy for optimizing benefits from type 2 diabetes prevention programs at minimum cost," says Dr. Zhuo.

The results are published in the American Journal of Preventive Medicine.

Reviewed by: 
Review Date: 
March 14, 2012
Last Updated:
March 15, 2012