In the last few years, many of us who treat people with diabetes have made a point of saying, “There is no such thing as borderline diabetes!” Either a person has diabetes or they don’t. This means that if a person has a blood test and their A1C is 6.5% or higher, or their fasting blood sugar is 7.0 mmol/L or higher, or their random sugar or 2-hour-post sugar challenge is 11.1 mmol/L or higher, then they have diabetes. These numbers were first determined as it was discovered that people with values above these cut-off points developed diabetic complications over time.
So, when it is said that it is not possible to have “borderline“ diabetes, it means that even though the values were just a bit above the cut-offs (for example, an A1C of 6.7% or a fasting blood sugar of 7.5 mmol/L), it is diabetes and not borderline or a touch of diabetes, and should be treated as such, with the aim of reaching normal targets and take medications that are recommended to protect the heart and kidneys.
What is prediabetes?
Prediabetes is a state where there is an increased risk of developing diabetes. People with prediabetes do not have blood test values that are high enough to be diagnosed with diabetes, but neither are their values in the normal range. The table below shows the Canadian Diabetes Association criteria for a diagnosis of prediabetes. People with prediabetes have about a 30% risk of developing diabetes within the next 3 years. As well, people with prediabetes have a higher risk of heart disease (but not the complication of diabetes, such as eye disease and kidney disease).
Fasting plasma glucose
2-hour plasma glucose following a 75-g oral glucose tolerance test
Diagnosis of prediabetes
It is important to know if a person has prediabetes, as studies have shown that certain lifestyle changes or medication can reduce the risk of developing diabetes. One large study showed that people who followed a low-calorie, low-fat, high-fibre diet, lost 5% of their initial body weight and performed 150 minutes of moderate physical activity per week, resulted in a 60% reduction of developing diabetes over 4 years. If people continued in the study, with support, these reductions in conversion to diabetes were sustained for 10 years.
A drug called metformin, which is used to treat diabetes, also reduces the incidence of converting to diabetes by 30%. Even when the drug is stopped, there is still a 25% reduction in converting.
What is metabolic syndrome?
Prediabetes and diabetes are often part of a multifaceted disorder called metabolic syndrome. This is a fairly common condition, which is characterized by a collection of abnormalities that include: abdominal obesity (large waist circumference), high blood pressure, high cholesterol and elevated blood sugars (similar to the levels associated with prediabetes). Click here for an explanation regarding how to take a proper waist measurement.
People with metabolic syndrome are at greater risk for heart disease; if an individual has prediabetes and also has metabolic syndrome, they have an even higher risk. It is important to reduce heart risk factors that are under a person’s control, such as smoking, being overweight and being sedentary.
If you are wondering if you or a family member is at risk of diabetes or prediabetes, try the CANRISK questionnaire, which looks at all your risk factors. If your risk is elevated, take the questionnaire results to your doctor and get tested!