HbA1c lowering models predict reductions in microvascular, macrovascular complications

In adults with type 2 diabetes and known cardiovascular disease, each 1% decrease in HbA1c is associated with a relative risk reduction in microvascular and macrovascular complications, according to lifetime simulation model results presented at the 52nd European Association for the Study of Diabetes Annual Meeting.

“These simulated outcomes provide patients and clinicians with an overview of the potential glucose-lowering benefits that might be obtained when targeting progressively lower HbA1c values,” Samiul A. Mostafa, PhD, MBChB, BSc, MRCP, a clinical lecturer and specialist registrar in the diabetes and endocrinology diabetes trials unit at the University of Oxford, and colleague wrote. “Running the [United Kingdom Prospective Diabetes Study] Outcomes Model for individual patients could give personalized risk reduction estimates to help inform their diabetes management.”

Samiul A. Mostafa

Mostafa and colleagues analyzed data from 5,717 patients with type 2 diabetes and known CVD participating in the TECOS trial (mean age, 66 years; 28% women; 85% white; type 2 diabetes duration, 11 years; 11% current smokers).

Using the United Kingdom Prospective Diabetes Study Outcomes Model version 2.0, researchers estimated 10-year risks for micro- and macrovascular complications for five different HbA1c measurements, running the model with values held constant at 10%, 9%, 8%, 7% and 6%; all other risk factors were also held constant at their initial values. Cumulative risk estimates were used to calculate RR decrements at progressively lower HbA1c values.

For a patient with an HbA1c of 10%, the 10-year estimated median risk for MI was 22.3% (95% CI, 21.9-22.6), with the risk progressively lowering at each 1% HbA1c decrement (P < .001 for trend). Cumulative RR reductions for each modeled 1% decrease in HbA1c were 4.6% for an HbA1c of 9%, 9.3% for an HbA1c of 8%, 15.1% for an HbA1c of 7% and 20.2% for an HbA1c of 6%.

The researchers observed similar trends for stroke, single-eye blindness, amputation and all-cause mortality. According to models, reducing HbA1c from 10% to 7% led to a 10-year RR reduction of 19.6% for stroke, 52.3% for amputation, 37.1% for single-eye blindness and 3.9% for all-cause mortality.

“Preventing complications in type 2 diabetes requires control of other modifiable risk factors,” Mostafa told Endocrine Today. “There is a need to repeat this research with a focus on systolic blood pressure and LDL cholesterol.” – by Regina Schaffer

Reference:

Mostafa S, et al. Poster #1137. Presented at: 52nd EASD Annual Meeting; Sept. 12-16, 2016; Munich.

Disclosure: Mostafa reports receiving research funding from the Academy of Medical Sciences Clinical Lecturer’s starter grant and the Oxford University Medical Research Fund.