We commend the Veterans Administration for implementing a clinical trial of the impact of glucose control on cardiovascular complications in patients with type 2 diabetes (1). Among people with diabetes, cardiovascular disease (CVD) is the leading cause of death (2); 27% have CVD, and an additional 71% have CVD risk factors (3). However, the burden of CVD can be substantially reduced by improving metabolic control, including that of glucose, lipids, blood pressure, and coagulation parameters (4). Published data from national surveys enable us to evaluate the current level and control of CVD risk factors among people with diabetes in the U.S.
In regard to glucose control, 37% of people with diabetes had HbA1c >8.0% according to the Third National Health and Nutrition Examination Survey (NHANES III) (5). Although the majority (73%) were taking either insulin or oral agents, 51% of those on insulin, 42% of those on oral agents only, and 15% of those on diet only had HbA1c >8%.
Among individuals with diabetes, 97% had at least one lipid abnormality (NHANES III) (6). Overall, 33% had LDL between 100 and 130 mg/dl, and 56% had LDL ≥130 mg/dl. Of diabetic individuals, 32% followed some type of treatment for high cholesterol, but only 9% were taking a lipid-lowering medication. Among those treated, only 1% had LDL <100 mg/dl, and 61% had LDL ≥130 mg/dl.
The prevalence of elevated blood pressure (≥130/85 mmHg or on antihypertensive medication) was 71% among U.S. people with diabetes (NHANES III) (7). Among those with elevated blood pressure, only 57% were on prescription medication.
Although nearly every U.S. adult with diabetes is eligible for aspirin treatment (3,4), aspirin was used by only 20% of diabetic individuals overall, 37% of whom had CVD, and 13% of whom had CVD risk factors (NHANES III) (3). Other risk factors in people with diabetes were also inadequate. Of people with diabetes, 26–34% had microalbuminuria (≥30 μg/ml) (NHANES III) (3,8), 34–54% were obese (BMI ≥30 kg/m2) (NHANES III) (8), 31% were sedentary, 35% were somewhat active, only 34% were regularly active according to the National Health Interview Survey (NHIS) (9), and 18–27% were smokers (NHIS and NHANES III) (8,10).
In conclusion, national data in the U.S. point to suboptimal control of CVD risk factors and substantial missed opportunities for awareness, treatment, and control of these risk factors in the diabetic population. Although the prevalence of CVD risk factors is higher among people with diabetes, the use of treatments for many CVD risk factors is not more prevalent among the diabetic population. In fact, CVD mortality for the U.S. diabetic population has not declined as much as it has for the nondiabetic population (2). Reduction in CVD mortality in the general population is a major achievement in recent decades, but people with diabetes deserve similar improvement. We look forward to seeing the results of the Veterans Affairs Diabetes Trial. We hope this trial will encourage future trials that will examine how control of other CVD risk factors (such as lipid levels, blood pressure, and coagulation parameters) may reduce morbidity and mortality associated with CVD among people with diabetes.
References
Address correspondence to Stephanie Benjamin, Division of Diabetes Translation, Centers for Disease Control and Prevention, 4770 Buford Highway, NE (MS-K68), Atlanta, GA 30341. E-mail: [email protected].
