Biomarker Goal Attainment Improves Life Expectancy in Patients with Type 2 Diabetes

Hui Shao, MD, PhD

New research suggested that achieving recommended goals in biomarkers is associated with an extension in the life expectancy of individuals with type 2 diabetes (T2D).

Data show patients from the lowest body mass index (BMI), hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and low-density lipoprotein cholesterol (LDL-C) population quartile had increased gains in life expectancy.

“Better control of biomarkers can potentially increase the [life expectancy] by 3 years in an average person with T2D in the US,” wrote study author Hui Shao, MD, PhD, Department of Pharmaceutical Outcomes and Policy, College of Pharmacy, University of Florida. “For individuals with very high levels of HbA1c, SBP, LDL-C, and BMI, controlling biomarkers can potentially increase [life expectancy] by more than 10 years.”

Determining life-years obtained from diabetes care is crucial for clinical practice and public health interventions, to aid in both shared-decision making and improved public policy.

The current study used outcomes from the Building, Relating, Assessing, and Validating Outcomes (BRAVO) diabetes model to quantify potential gains in life expectancy in achieving different levels of the above variables in a representative population of US adults with T2D.

In order to calibrate the model for the general population, investigators built a calibration sample from the 2009 - 2010 National Health and Nutrition Examination Survey (NHANES) and linked mortality records from the National Death Index.

A total of 421 individuals with T2D were included in the study, with a mean age of 65.6 years and 46% women (n = 194). Investigators grouped each measured biomarker (HbA1c, SBP, LDL-C, and BMI) into quartiles. The life expectancy gains associated with better control were estimated by moving those with T2D from the current quartile of each biomarker to the lower quartile.

In terms of glucose control, a reduction in HbA1c from 9.9% (mean, Q4) to 7.7% (mean, Q3) was associated with a 3.4 year gain in life expectancy. However, a reduction from 7.7% to 6.8% (mean, Q2) was associated with only a mean of 0.5 years gain and 6.8% to 5.9% (mean, Q1) had no benefit in life expectancy.

Overall, investigators found a reduction in HbA1c from Q4 to Q1 had a life expectancy gain of 3.8 years.

In comparison to a BMI of 41.4 (mean, Q4), a lower BMI level of 24.3 (mean, Q1), 28.6 (mean, Q2), and 33.0 (mean, Q3) were associated with a mean of 3.9, 2.9, and 2.0 additional life-years, respectively.

For individuals with a SBP level of 160.4 mm Hg (mean, Q4), a lower SBP level of 114.1 mm Hg (mean, Q1), 128.2 mm Hg (mean, Q2), and 139.1 mm Hg (mean, Q3) were associated with 1.9, 1.5, and 1.1 year gain in life expectancy, respectively.

Moreover, a lower LDL-C level of 59 mg/dL (mean, Q1), 84.0 mg/dL (mean, Q2) and 107.0 mg/dL (mean, Q3) was associated with a mean of 0.9, 0.7, and 0.5 additionally life-years, compared with an LDL-C level of 146.2 mg/dL (mean, Q4).

Investigators found the benefit associated with treatment goal achievement had a sharp decline as a patient aged. For a male patient aged 50 - 60 years, a reduction in BMI from 35 to 30 was associated with an increase of 1.4 years. For a male patient aged 70 to 80, a reduction in BMI to 30 was only associated with an additional 0.6 years.

“This finding emphasizes the importance of biomarker control at an earlier age,” Shao said. “It also highlights the potential need for a trade-off between life quality and treatment for elderly patients when the benefit of biomarker control is limited.”

The study, “Potential Gains in Life Expectancy Associated With Achieving Treatment Goals in US Adults With Type 2 Diabetes,” was published in JAMA Network Open.