November is American Diabetes Month: Prediabetes affects heart disease, stroke risk

Also called impaired glucose tolerance or fasting glucose, prediabetes is defined by blood sugar levels higher than normal but not yet in the diabetic range.

According to the Centers for Disease Control and Prevention (CDC), normal fasting blood sugar is 99 mg/dL or lower. Fasting blood sugar of 100 to 125 mg/DL indicates prediabetes.

About 38 percent of Americans over the age of 18 are now classified as prediabetic. Most of these people are not aware of their condition.

Early diagnosis is important. Cardiovascular disease, which is the primary cause of death among people with diabetes, begins to develop in the prediabetic phase. The risk can begin to climb for 15 years before type 2 diabetes is diagnosed.

Unless people with prediabetes take steps to reduce their risk, 5 to 10 percent of them will develop type 2 diabetes each year. According to the National Institutes of Health, within ten years, up to half of them will progress to full-blown diabetes, a leading cause of blindness, kidney failure, amputations, and premature death from heart disease.

A study reported in The New England Journal of Medicine shows that lifestyle changes and the anti-diabetes drug metformin are effective at preventing or delaying type 2 diabetes risk.

In the study, 58 percent of those on a lifestyle program reduced their incidence of diabetes, compared with 31 percent taking metformin. The lifestyle program included a healthy, low-calorie, low-fat diet and exercising at least 150 minutes per week with a 7 percent weight loss goal.

Drugs are available for the treatment of prediabetes, but lifestyle changes are the first-line treatment of choice.