Screening Initiatives Are Needed to Identify Undiagnosed Diabetes

Prediabetes and unknown diabetes decreased during a 12-year screening campaign among individuals aged 40 to 70 years, but prevalence continues to remain high, according to study results published in Cardiovascular Diabetology.

Approximately 25% of individuals with diabetes do not receive an official diagnosis, suggesting initiatives to improve diabetes screening are needed. Study authors sought to determine the prevalence of prediabetes and undiagnosed diabetes among individuals residing in an urban setting aged 40 to 70 years.

The researchers included 32,675 participants (median age, 56 years; 45.4% men) in the investigation, which took place between January 2007 and December 2018, after inviting individuals who were covered by social health insurance to receive a free screening at 1 of 17 medical centers. Participants underwent screening for fast plasma glucose (FPG), total cholesterol, low-density lipoprotein-cholesterol (LDL-c), high-density lipoprotein-cholesterol (HDL-c), and triglycerides after observing a 12-hour fast.

Using World Health Organization (WHO) criteria, the team defined undiagnosed diabetes as FPG of 7.0 mmol/l or higher and prediabetes as FPG levels between 6.1 mmol/l and 7.0 mmol/l. The team also considered prediabetes prevalence according to American Diabetes Association (ADA) criteria (5.6 mmol/l ≤ FPG < 7 mmol/l). Individuals with known diabetes comprised 5.9% (95% CI, 5.6%-6.1%) of the study sample, 36.4% were overweight (95% CI, 35.9%-36.9%), and 18.7% had obesity (95% CI, 18.2%-19.1%).

Among individuals with no previous diabetes diagnosis (n=30,759), 8.1% (95% CI, 7.8%-8.4%) had prediabetes based on WHO criteria. According to ADA standards, 27.2% (95% CI, 26.7%-27.7%) had prediabetes, and 2.3% (95% CI, 2.1%-2.5%) had diabetes. Compared with individuals with no diabetes, participants with prediabetes and unknown status were more likely to be older, men, and overweight or obese.

Throughout the 12-year campaign, prediabetes, unknown diabetes, and known diabetes decreased among individuals aged 45 to 64 years (P <.001). The prevalence of prediabetes among participants aged 55 to 64 years, however, did not change significantly (P =.27).

Study limitations include an inability to obtain information pertaining to participants’ ethnicities and a possible overrepresentation of individuals with higher incomes.

“Our results show that the prevalence of prediabetes and unknown diabetes is high, but is decreasing in France over a 12-year period, and about one-quarter of diabetes cases remain undiagnosed,” according to the researchers. “These results highlight the need to support primary prevention, and to enhance secondary prevention of prediabetes and diabetes, especially through promotion of screening in populations at risk.”