Promoting Early Diagnosis and Treatment of Type 2 Diabetes: Title and subTitle BreakThe National Diabetes Education Program

Diabetes mellitus exacts an enormous toll in the United States by decreasing quality of life and causing death and disability, all at a huge economic cost. Yet simple diagnostic criteria and effective treatment choices that prevent or delay the onset of costly diabetes complications are readily available to health care professionals. It is time for health care professionals and patients with diabetes to take action together to reduce premature morbidity and mortality from diabetes-caused disease. The National Diabetes Education Program is the first joint diabetes initiative of the National Institutes of Health and the Centers for Disease Control and Prevention and involves public and private partnerships to promote early diagnosis and improve the treatment and outcomes for patients with type 1 and type 2 diabetes mellitus.

It is estimated that in the United States, type 2 diabetes can be present for up to 9 to 12 years before initial clinical diagnosis.¹ Microvascular disease progresses during this time, causing 15% to 20% of patients to have retinopathy^{1 - 2} and 5% to 10% to have proteinuria at the time of diagnosis.³ Patients with type 2 diabetes have high rates of hypertension, dyslipidemia, and obesity, major reasons for their 2- to 4-fold higher rates of cardiovascular disease.⁴ Type 2 diabetes is occurring increasingly in younger people.⁵ Although every patient can be expected to benefit from any increment in improved glycemic control, blood glucose control is more effective in preventing the initial development of microvascular complications than in preventing the progression of complications once they have become established.^{4 ,6 - 7} This finding underscores the need for aggressive treatment as soon as type 2 diabetes is diagnosed.

Diabetes accounts for almost $100 billion in direct medical costs and indirect expenditures attributable to diabetes each year.⁸ Further, while patients with diabetes represented 4.5% of the US population in 1992, they accounted for 15% of total US health care expenditures and 27% of Medicare expenditures.⁹

There is a marked correlation between glycemic control of diabetes as measured by glycosylated hemoglobin (HbA_1c) testing and the cost of medical care. Medical care charges increase significantly for every 1% increase in HbA_1c level above 7%.¹⁰ In 1994, excess expenditures for patients with diabetes in a managed care setting totaled $282.7 million or $3494 per person—2.4 times the cost for control subjects. Nearly 38% of the total excess was spent treating the long-term complications of diabetes, predominantly coronary heart disease and end-stage renal disease.¹¹ Because of its high and increasing prevalence, type 2 diabetes contributes a significant portion of these costs.

There is substantial evidence that the human and economic burden of diabetes can be reduced significantly by early, aggressive therapeutic intervention. The Diabetes Control and Complications Trial⁶ and the United Kingdom Prospective Diabetes Study (UKPDS)⁷ demonstrated that intensive blood glucose control for patients with type 1 and type 2 diabetes significantly reduced the risk for retinopathy, nephropathy, and neuropathy. Lowering blood pressure in a subset of UKPDS patients to a mean of 144/82 mm Hg reduced the risk of strokes, diabetes-related deaths, heart failure, microvascular complications, and vision loss up to 56%.¹² Aggressive lipid reduction therapy also can reduce the risk of coronary heart disease in patients with diabetes. Primary therapy should be directed first at lowering low-density lipoprotein levels with the statin class of drugs if necessary, then giving attention to treatment of residual hypertriglyceridemia and low high-density lipoprotein levels.¹³

Modeling analyses indicate that these early therapeutic interventions are cost-effective.¹⁴ Glycemic control also can result in short-term benefits, including improved quality of life, work productivity, and health care use.¹⁵ Aggressive treatment of type 2 diabetes is probably warranted in any patient with a significant life expectancy (>5-10 years).¹⁶

Despite the high cost of diabetes and the significant improvement in health outcomes associated with aggressive management, current treatment of type 2 diabetes frequently fails to meet desirable treatment goals. Recently reported data from the Third National Health and Nutrition Examination Survey show that more than half (54%) of patients with type 2 diabetes in the United States have HbA_1c levels greater than 7%, the level above which the risk for the microvascular complications of diabetes significantly increases. Further, 37% of patients are markedly hyperglycemic, with HbA_1c values greater than 8%.¹⁷

Data from community studies of patients with diagnosed diabetes show that the average fasting and postprandial plasma glucose values were greater than accepted target levels, and that approximately 74% of patients were hypertensive and 71% had elevated cholesterol levels.¹⁸ Glycosylated hemoglobin testing to assess glycemic control is underused, with estimates of its use ranging from 50% in adults with diabetes to 16% in patients covered by Medicare Part B.^{19 - 20} In 1994, 75% of an adult sample of patients with diabetes reported that they had not heard of the HbA_1c test.²¹

Successful treatment of type 2 diabetes must become a high priority. The routine diagnostic test for diabetes is now a fasting plasma glucose test performed twice rather than the previously preferred oral glucose tolerance test.²² Once diagnosed, there are several effective diabetes treatment choices. A proactive management plan for the control of glycemia, lipid levels, and hypertension should have defined goals and targets and meet accepted clinical guidelines.²³ Nutrition and exercise therapy, along with oral hypoglycemic agents used singly, in combination, or with insulin, allow treatment to be tailored to patient needs.¹⁶ Glycosylated hemoglobin testing should be used regularly to monitor therapy success. A progressive or stepped approach is helpful to intensify therapy until management goals are met. Effective diabetes care also requires long-term patient and clinician attention to the principles of self-care, a healthy lifestyle, preventive services, and cardiovascular risk factor management.²⁴

A chronic disease such as type 2 diabetes requires a health system that promotes long-term management.^{25 - 27} Many large clinics and managed care organizations have recognized the savings that can be realized from disease management programs focused on the prevention of diabetes complications. These programs attribute much of their success to organizational structure and reimbursement practices, multidisciplinary team care that incorporates patient self-management, and the use of management protocols and computerized information systems.^{26 ,28 - 32}

Among the public and private initiatives that are addressing the challenges of diabetes, the National Diabetes Education Program is serving as a catalyst to coordinate, extend, and contribute to these ongoing efforts. The program currently is implementing public awareness, patient education, and clinician information strategies nationwide to increase understanding of the seriousness of diabetes, its risk factors, and its effective management.