Which of these is not a risk factor for prediabetes?

A) Overweight

B) Age 45 or older
C) Being white
D) Exercise less than three times per week

The correct response is C — the actual risk factor being African American, Latino, Native American or Asian American. If you didn’t get it right, don’t feel badly. Chances are your doctor wouldn’t either, according to the results of a new national survey of primary care physicians (PCPs) conducted by Johns Hopkins Medicine researchers.

In a report on their findings in the Journal of General Internal Medicine (JGIM), the researchers say their survey of 1,000 randomly selected PCPs revealed significant gaps in the group’s overall knowledge of risk factors, diagnostic criteria and recommended management/prevention practices for prediabetes.

The researchers also say the gaps may result from a health care education and reimbursement system that encourages doctors to prioritize treating diabetes once the disease occurs rather than working with patients to prevent it.

“Our survey findings suggest that these gaps contribute to doctors underscreening for and missing diagnoses of prediabetes, and in turn, not referring patients to type 2 diabetes prevention programs,” says Eva Tseng, M.D., M.P.H., an assistant professor of general internal medicine at the Johns Hopkins University School of Medicine and lead author of the JGIM paper.

“Along with closing the PCP knowledge gaps our survey identified, we believe the problem needs to be addressed at the health care system level,” says Nisa Maruthur, M.D., M.H.S., a Johns Hopkins associate professor of medicine and a co-author of the JGIM paper. “This includes concerted efforts to make both health care providers and patients more aware of available type 2 diabetes prevention programs, encouraging patient enrollment in these programs, and getting insurance companies to understand their value and cover the costs.”

According to the U.S. Centers for Disease Control and Prevention, prediabetes is a serious health condition in which blood sugar levels are higher than normal, but not high enough to meet the threshold for type 2 diabetes. The federal agency says that some 84 million Americans ages 18 or older — more than one out of three — have prediabetes but 90% don’t know it. If diagnosed early, experts say, lifestyle changes such as weight loss and regular exercise can prevent or delay the development of type 2 diabetes and the increased risks it poses for heart disease, stroke, kidney failure and nerve damage.

For their new study, the Johns Hopkins researchers sent surveys to 1,000 PCPs randomly selected from the American Medical Association’s Physician Masterfile which includes data on more than 1.4 million physicians, residents and medical students in the United States. Candidates for the survey included general practitioners who had completed residency training, general internists and family physicians.

Survey questions evaluated a physician’s knowledge of (1) risk factors that should prompt prediabetes screening, laboratory criteria for diagnosing prediabetes, and recommendations for prediabetes management, (2) practice behaviors regarding prediabetes management and (3) perceived barriers and potential interventions to improve prediabetes management.

For example, from a list of risk factor, PCPs were asked to select the ones that would lead them to order prediabetes screening for a patient. In another example, they were queried about their knowledge, understanding and use of prediabetes screening such as fasting blood glucose, two-hour oral glucose tolerance and hemoglobin A1c (HbA1c) tests — all standard measures of blood sugar.

The researchers received 298 completed surveys, or 34% of the 888 ultimately found eligible for inclusion in the study. “Our results revealed that there are substantial gaps in the knowledge that PCPs have in all three categories we tested,” Tseng says.

For instance:

• On average, respondents selected just 10 out of 15 correct risk factors for prediabetes, most often missing that African Americans and Native Americans are two groups at high risk.
• Only 42% of respondents chose the correct values of the fasting glucose and Hb1Ac tests that would identify prediabetes.
• Only 8% knew that a 7% weight loss is the minimum recommended by the American Diabetes Association as part of a diabetes prevention lifestyle change program.

“Our results also suggests that 25% of PCPs may be identifying people as having prediabetes when they actually have diabetes, which could lead to delays in getting those patients proper diabetes care and management,” Maruthur says.

Based on their findings, the researchers suggest strategies to address the PCP knowledge gaps about prediabetes, as well as the system-level obstacles to preventing type 2 diabetes. These include better educating physicians about diabetes prevention, providing easier access for both PCPs and their patients to national diabetes prevention lifestyle change programs, increasing insurance coverage of such programs, and offering new tools to help PCPs improve the procedures and practices by which they diagnose and treat patients with prediabetes.

“We believe that what was learned from our survey can have implications for changing national guidelines and policies regarding type 2 diabetes prevention, including establishing measures of quality for diagnosing and managing prediabetes,” Tseng says. “The public can help by advocating for more insurers to cover prevention programs, along with insisting that public health stakeholders expand access to and availability of these interventions.”

Besides Tseng and Maruthur, members of the Johns Hopkins Medicine research team are Raquel Greer, M.D., M.H.S.; Paul O’Rourke, M.D., M.P.H.; Hsin-Chieh Yeh, Ph.D.; Maura McGuire, M.D.; Ann Albright, Ph.D.; Jill Marsteller, Ph.D., M.P.P.; and Jeanne Clark, M.D., M.P.H.

The study was funded by a Johns Hopkins Primary Care Consortium grant. None of the authors had a conflict of interest.