Cardiovascular disease continues to be a major cause of morbidity and mortality in patients with diabetes and prediabetes, and the prevalence of diabetes and prediabetes is expected to exponentially increase over the next 30 years. The global burden of cardiovascular disease has emerged, not only in the developed world but also in low- and middle-income countries. As a result, the major focus in type 1 diabetes patients and type 2 diabetes patients is the prevention of the development of cardiovascular disease. Recently, the American Diabetes Association (ADA) published their recommendations for practice regarding cardiovascular disease risk management in Diabetes Care in January 2016.1
The universally recognized criteria for the diagnosis of prediabetes and diabetes are as follows: (1) a normal glycated hemoglobin should be less than 5.7%, (2) a glycated hemoglobin of 5.7% to 6.4% is considered prediabetes, and (3) a level of 6.5% or higher on two separate occasions indicates diabetes.1 Prediabetes can be diagnosed by a fasting plasma glucose of 100 mg/dL or more (impaired fasting glucose), a postglucose load of 140 to 199 mg/dL (impaired glucose tolerance), or both. Other recognized criteria include a fasting plasma glucose greater than 126 mg/dL or a 2-hour postprandial glucose of greater than 200 mg/dL during an oral glucose tolerance test involving a glucose solution containing the equivalent of 75 grams of glucose dissolved in water. Diabetes can also be diagnosed in the patient who has a random plasma glucose of greater than 200 mg/dL with classic symptoms of hyperglycemia.
With regard to classification and diagnosis of diabetes, a number of important classification issues need to be clarified. Apart from the classification of type 1 and type 2 diabetes, gestational diabetes is the diagnosis of diabetes in the absence of overt diabetes made in the second or third trimester of pregnancy.
The new recommendations also identified patients who are at increased risk for diabetes and who require testing. These include patients who were overweight or obese, with a body mass index (BMI) of greater than 25 kg/m2 or, in the case of Asian Americans, of 23 kg/m2 or higher. Recommendations for screening for diabetes have now expanded to screening of children and adolescents who are overweight or obese. With regard to gestational diabetes, patients are tested in the first prenatal visit with risk factors. At 28 weeks of gestation, there is a test for gestational diabetes in pregnant women who are not previously known to have diabetes. It is recommended that women with a history of gestational diabetes are considered to have prediabetes and should receive lifestyle interventions for the prevention of diabetes.
Patients with similar mean glucose or glycosylated glycated hemoglobin values can have markedly different daily glucose profiles depending on the numbers and duration of glucose excursions. In 1970, Service and colleagues ...