USPSTF Lowers Age for Diabetes, Prediabetes Screening to 35

The U.S. Preventive Services Task Force (USPSTF) has dropped the recommended age for screening for prediabetes and type 2 diabetes from 40 to 35

The screening recommendations, published today in JAMA, apply to people who have overweight or obesity.

The USPSTF screening guidelines are narrower than those from the American Diabetes Association guidelines, which recommend universal screening, regardless of risk factors, for all adults, ages 45 and older, and screening of all adults who have overweight and obesity and one or more risk factors for diabetes.

USPSTF says it lowered the age to 35 because of evidence that the incidence of diabetes starts to increase at that age. The recommendations also rest on evidence that interventions benefit people with newly diagnosed diabetes.

Still, these are not USPSTF’s strongest recommendation. The task force ranks the strength of its recommendation based on the underlying evidence and this recommendation got a “B” ranking. The USPSTF says that it concluded with “moderate certainty” that screening for prediabetes and type 2 diabetes and offering preventive interventions has a “moderate net benefit.”

The task force article in JAMA points to results from a British study as evidence that intensive glucose control of people with newly or recently diagnosed type 2 diabetes lowers the risk of heart attacks and mortality from diabetes and mortality in general. The article also cites a meta-analysis that included 23 trials as showing that lifestyle interventions (healthier diets, more physical activity) reduce the risk of prediabetes worsening and become full-fledged diabetes. There is also trial evidence of metformin lessening the risk of prediabetes developing into diabetes.

Results of several different types of tests of blood sugar levels are the main way patients are grouped into prediabetes and the full-fledged disease. A fasting plasma glucose level of 126 mg/dL or greater; A1C level of 6.5% or higher; or a two-hour postload glucose of 200 mg/dL are consistent with the diagnosis of type 2 diabetes. The prediabetes values for the same tests are, respectively 100 to 125 mg/dL, 5.7% to 6.4%, and 140 to 199 mg/dL.

Results from the influential Diabetes Prevention Program (DPP) showed that lifestyle interventions were more effective than metformin in preventing or delaying the onset of diabetes, according to the USPSTF JAMA article. Metformin helps with being overweight but doesn’t affect blood pressure or consistently improve lipid articles, says the article in JAMA.

An editorial in JAMA Internal Medicine expressed some reservations about the new recommendations. Richard W. Grant, M.D., M.P.H., of the Kaiser Permanente Northern California division of research; Anjali Gopalan, M.D., M.S., an associate editor of the JAMA Internal Medicine; and Marc G. Jaffe, M.D., of the Permanente Medical Group at the San Francisco Medical Center, observed that there are doubts that people benefit from an early diagnosis of diabetes in clinical practice and outside the very controlled situation of a clinical trial. Evidence-based strategies have been challenging to implement, they say, because of the resources required, limitations on reimbursement and patient out-of-pocket costs.

Grant, Gopalan and Jaffe also argue that increased screening for prediabetes and type 2 diabetes must be linked to “robust public health measures to address the underlying contributors. To date, such public health efforts have had limited success in blunting these social factors.”

They also caution that influx of newly diagnosed Black and Latino young adults could worsen disparities in diabetes treatment and outcomes because of the high cost of treatments and other factors.