Could a routine blood test predict the development of diabetes?

Written by Ilana Landau, Editor

A multi-system Veterans Affairs (DC, USA) study has observed that blood sugar measurements made in routine, outpatient blood tests could predict patients’ likelihood of developing diabetes.

According to the Centers for Disease Control and Prevention (GA, USA), more than 7 million individuals with diabetes go undiagnosed every year in the USA. Delayed diagnosis increases the likelihood of diabetes-related health complications developing before treatment is provided. A new study has assessed whether random plasma glucose measurements made in routine outpatient blood tests could facilitate diabetes diagnosis.

Researchers employed a retrospective cohort study design and analyzed data on 942,446 non-diabetic, US veterans.

Study participants were required to have had more than three random plasma glucose measurements made during a baseline year — often measured by chance during routine blood tests — and at least one primary care visit per year, for five follow-up years.

Currently, the American Diabetes Association (VA, USA) only recommends using random plasma glucose test measurements for testing for diabetes, if the test is accompanied by diabetes-related symptoms presentation; random plasma glucose tests are not considered useful for diabetes screening.

Random plasma glucose measurements of 200 mg/dL, or higher, are the threshold for diabetes diagnosis.

Over the course of the 5-year follow-up period, 94,599 of the 942,446 study participants developed incident diabetes, as determined by diagnostic codes and prescription of a diabetes therapy.

Researchers observed that elevated random plasma glucose measurements — that were still below the 200mg/dL diabetes diagnosis threshold level — successfully predicted the individuals’ development of diabetes.

Study participants with a minimum of two random plasma glucose measurements of at least 115 mg/dL, over a 12-month period, had an increased likelihood of developing diabetes compared with individuals who did not present with such measurements. Individuals with random plasma glucose measurements of 130mg/dL, or higher, had an even greater likelihood of developing diabetes.

As expected, researchers noted that patients’ demographic characteristics — such as age, sex, smoking status and BMI — were correlated with increased likelihood of diabetes development. However, scientists observed that high — though still below diagnosis threshold — random plasma glucose measurements were most strongly correlated with the prediction of diabetes development.

Mary Rhee, lead study author and Physician–Researcher at Atlanta Veteran Affairs Health Care System and Emory University (both GA, USA), commented: “These findings have the potential to impact care in the VA and in the general U.S. population…as random plasma glucose levels — which are convenient, low-cost and ‘opportunistic’ — could appropriately prompt high-yield, focused diagnostic testing and improve recognition and treatment of prediabetes and early diabetes.”

Sources:

Rhee MK, Ho Y-L, Raghavan S et al. Random plasma glucose predicts the diagnosis of diabetes. PLoS ONE, 14(7): e0219964 (2019);

https://www.research.va.gov/currents/0719-Blood-tests-for-diabetes.cfm