Diabetes has assumed epidemic proportions, ranking as the sixth leading cause of death and the costliest chronic disease in the United States.1 Reduced physical activity among Americans, increased caloric intake, and the resultant elevated rates of overweight and obesity have fueled the dramatic increase in the prevalence of this disease. Worldwide, an estimated 194 million people have diabetes. That number is expected to climb to 221 million by the end of this decade and to 333 million by the year 2025,2 posing an enormous global public health and community burden. Clinicians are often ill-prepared to manage diabetes, which contributes to poor outcomes and increased morbidity and mortality.
Standards of care
Clinical trials Results of multicenter clinical trials have highlighted the relationship between metabolic control of diabetes and its vascular complications. The landmark 1993 Diabetes Control and Complications Trial demonstrated the importance of maintaining tight glycemic control in delaying or preventing microvascular sequelae in type 1 diabetes.3 A 1.3% difference in average glycosylated hemoglobin (A1C) levels between the conventional and intensive treatment groups led to 60% and 54% reductions in neuropathy and albuminuria, respectively, and reduced the adjusted mean risk for the development of retinopathy by 76%. The United Kingdom Prospective Diabetes Study (UKPDS) in 1998 produced similar conclusions for type 2 diabetes.4 Patients were treated with sulfonylureas, metformin, and insulin. In addition to a reduction in microvascular complications, improved glycemic control also produced a statistically nonsignificant trend towards decreased macrovascular risk.
The publication of these and other studies gave an unprecedented impetus toward establishing improved 
glycemic goals. Various organizations proposed guidelines and standards of care for screening, diagnosing, and treating patients with diabetes, among them the World Health Organization, the American Diabetes Association (ADA), and the American College of Endocrinology (ACE).
The ADA recommends that adults be evaluated with a fasting blood glucose level every 3 years starting at age 45 years and sooner if there are risk factors.5 ADA recommendations for glycemic, BP, and lipid goals for diabetic patients are listed in Table 1. An A1C value of less than 7% is the optimal value, although it is better to individualize targets. Diabetes was designated a cardiac risk equivalent by the National Cholesterol Education Program (NCEP) 2001 guidelines,6 based on evidence that patients with diabetes have the same risk of MI as those without diabetes who have already had an MI. NCEP mandated a target LDL cholesterol level of less than 100 mg/dL in all patients with diabetes.7 The 2004 Adult Treatment Panel III update additionally recommends lowering the level of LDL cholesterol to less than 70 mg/dL in patients with both diabetes and cardiovascular disease (CVD) and to consider statin therapy regardless of baseline LDL levels.8 Recommendations for screening and treating microvascular complications of diabetes are listed in Table 2. Preconception counseling and care can reduce pregnancy-related morbidity and risk of congenital malformations.
Diabetes outcomes In the United States, there are benchmarks for evaluating quality of care and attaining specific goals and outcomes for chronic conditions such as diabetes. The National Committee for Quality Assurance (NCQA) maintains a list of accredited and certified diabetes disease management programs.9 In partnership with the ADA, it has cosponsored the Diabetes Physician Recognition Program, which assesses physician performance on 11 key measures of patient care for adults and 8 measures for pediatric patients. The NCQA also sponsors and supports the Health Plan Employer Data and Information Set (HEDIS), measures of standardized performance designed to ensure that patients have the information they need to compare managed health care plans. The performance measures in HEDIS are related to many significant public health and chronic issues, including diabetes.
The Diabetes Quality Improvement Project (DQIP)9 began through a coalition of public and private entities (the 
ADA, Foundation for Accountability, Health Care Financing Administration, NCQA) and was joined by the American Academy of Family Physicians, the American College of Physicians, and the Veterans Administration. The DQIP's committee of experts recommended a set of diabetes-specific performance and outcome measures with which plans, clinics, physicians, and other health care providers could be compared for the purposes of accountability. Diabetes-related data for ongoing collection and monitoring include patient characteristics, measures of glycemic control, laboratory values, and screening for complications and comorbidities. Parameters are designed to be tracked over time and used for feedback, quality improvement, and research.
Barriers to optimal management
In the past decade, the concept of diabetes care has evolved into an aggressive and goal-oriented philosophy, as the result of solid evidence showing that tight glycemic control and intensive risk-factor modification reduce long-term risk and improve health outcomes.4,5 Unfortunately, translating these principles into clinical practice so patients with diabetes can benefit remains an obstacle, and recent studies show that in spite of the grim statistics, most diabetic patients are not achieving treatment goals.10 In type 2 diabetes, the management of comorbid conditions such as hypertension and hyperlipidemia is not being aggressively pursued.3,11 The Third National Health and Nutrition Examination Survey data confirmed that glycemic, BP, and lipid control in patients with diabetes was suboptimal.12 The current state of diabetes care clearly falls short of commonly accepted standards, and a large gap exists between optimal and actual care.
Obstacles to achieving goals The barriers that prevent evidence-based goals from being achieved can be summarized as follows:
- Clinical inertia—the acceptance of the status quo, so patients and providers are reluctant to escalate and intensify therapy.13 This inertia stems from an interplay of related factors: not realizing the seriousness of the disease process and clinician complacency.
- Infrequent follow-up of patients with diabetes. Patients whose medications are being titrated to achieve optimal glycemic control need detailed visits every 2 to 4 weeks and therapy modifications when necessary. Unfortunately, current managed care and time constraints are impediments in this regard.14
- Health care professionals' ignorance concerning the use of evidence-based guidelines15 and lack of awareness of available resources for diabetes education.
- Inability or unwillingness of patients to make lifestyle changes and adhere to complex medication regimens and appointment schedules.16
- Problems with accessibility, cost of medical care, and insurance coverage.17
Recent changes in the approach to diabetes, some in response to the above-mentioned barriers, are discussed below.