Upon successful completion of this course, you will be able to:

• List and discuss the current Standards of Medical Care in Diabetes
• Explain the existing systems for the Classification and Diagnosis of diabetes
• Discuss the processes of DETECTION AND DIAGNOSIS OF GDM
• Explain the differences of DIABETES CARE IN SPECIFIC POPULATIONS
• Identify and discuss the systems for Diagnosis and Classification of Diabetes Mellitus
• Explain the Diabetes Care in the School and Day Care Setting

The American Diabetes Association (ADA) has been actively involved in the development and dissemination of diabetes care standards, guidelines, and related documents for many years. These statements are published in one or more of the Association’s professional journals. This supplement contains ADA’s "Standards of Medical Care in Diabetes," our major position statement, which contains all or key recommendations. In addition, contained herein are selected position statements on certain topics not adequately covered in the "Standards." We hope that this is a convenient and important resource for all health care professionals who care for people with diabetes.

ADA Clinical Practice Recommendations consist of position statements that represent official ADA opinion as denoted by formal review and approval by the Professional Practice Committee and the Executive Committee of the Board of Directors. ADA Statements, consensus statements, and technical reviews are not official ADA recommendations; however, they are produced under the auspices of the Association by invited experts. These publications are reviewed by the Professional Practice Committee for general content and used as source documents for the updating of the "Standards."

ADA has adopted the following definitions for its clinically related reports.

An official point of view or belief of the ADA: Position statements are issued on scientific or medical issues related to diabetes. They are published in ADA journals and other scientific/medical publications as appropriate. Position statements must be reviewed and approved by the Professional Practice Committee and, subsequently, by the Executive Committee of the Board of Directors. ADA position statements are typically based on a technical review or other published review and are peer reviewed on an annual basis.

ADA Statement

A focused review on a clinical topic with recommendations. It is authored, and the recommendations are those of the authors based on the evidence presented. ADA Statements are reviewed externally and also by the Professional Practice Committee for overall content. As noted above, the recommendations made are considered by the Professional Practice Committee as part of the review and updating of the "Standards of Medical Care in Diabetes."

Technical Review

A balanced review and analysis of the literature on a scientific or medical topic related to diabetes. The technical review provides a scientific rationale for a position statement and undergoes peer review before submission to the Professional Practice Committee for approval. In some cases, in place of a technical review, original research publications, conference proceedings, or other comprehensive review articles are used as a basis for a position statement.

Consensus Statement

A comprehensive examination by a panel of experts (i.e., consensus panel) of a scientific or medical issue related to diabetes. A consensus statement is developed immediately following a consensus conference at which presentations are made on the issue under review. The statement represents the panel’s collective analysis, evaluation, and opinion based in part on the conference proceedings. The need for a consensus conference arises when clinicians or scientists desire guidance on a subject for which there is a relative deficiency of "evidence" that might otherwise allow a more definite statement to be made. Once written by the panel, a consensus statement is not subject to subsequent review or approval and does not represent official Association opinion.

The Association’s Professional Practice Committee is responsible for reviewing official position statements. Appointment to the Professional Practice Committee is based on excellence in clinical practice and research. The committee comprises physicians, diabetes educators, and registered dietitians who have expertise in a range of areas, including adult and pediatric endocrinology, epidemiology and public health, lipid research, hypertension, and preconception and pregnancy care. The committee regularly reviews each previously approved statement and makes necessary revisions. Both new and revised position statements are also reviewed by outside experts, after which they are approved by the Executive Committee.

Grading of Scientific Evidence

Since the ADA first began publishing practice guidelines, considerable evolution has occurred in the evaluation of scientific evidence and in the development of evidence-based guidelines. Accordingly, we have developed a classification system to grade the quality of scientific evidence supporting ADA recommendations. The system outlined in Table 1 will be used for all new and revised ADA position statements.
Recommendations have been assigned ratings of A, B, or C, depending on the quality of evidence (Table 1). Expert opinion (E) is a separate category for recommendations in which there is as yet no evidence from clinical trials, in which clinical trials may be impractical, or in which there is conflicting evidence. Recommendations with an "A" rating are based on large well-designed clinical trials or well-done meta-analyses. Generally, these recommendations have the best chance of improving outcomes when applied to the population to which they are appropriate. Recommendations with lower levels of evidence may be equally important but are not as well supported. This supplement contains seven statements that have used this system. The level of evidence supporting a given recommendation is noted either as a heading for a group of recommendations or after a given recommendation in parentheses.

Table 1— ADA evidence grading system for clinical practice recommendations

* Either all patients died before therapy and at least some survived with therapy or some patients died without therapy and none died with therapy. Example: use of insulin in the treatment of diabetic ketoacidosis.

Of course, evidence is only one component of clinical decision-making. Clinicians care for patients, not populations; guidelines must always be interpreted with the needs of the individual patient in mind. Individual circumstances, such as comorbid and coexisting diseases, age, education, disability, and, above all, patients’ values and preferences, must also be considered and may lead to different treatment targets and strategies. Also, conventional evidence hierarchies, such as the one adapted by the ADA, may miss some nuances that are important in diabetes care. For example, while there is excellent evidence from clinical trials supporting the importance of achieving glycemic control, the optimal way to achieve this result is less clear. It is difficult to assess each component of such a complex intervention.

The ADA will continue to improve and update the Clinical Practice Recommendations to ensure that clinicians, health plans, and policy makers can continue to rely on them as the most authoritative and current guidelines for diabetes care.

American Diabetes Association

Abbreviations: ABI, ankle-brachial index • AMI, acute myocatdial infarction • ARB, angiotensin receptor blocker • CAD, coronary artery disease • CBG, capillary blood glucose • CHD, coronary heart disease • CHF, congestive heart failure • CKD, chronic kidney disease • CVD, cardiovascular disease • DCCB, dihydropyridine calcium channel blocker • DCCT, Diabetes Control and Complications Trial • DKA, diabetic ketoacidosis • DMMP, diabetes medical management plan • DPN, distal symmetric polyneuropathy • DPP, Diabetes Prevention Program • DRI, dietary reference intake • DRS, Diabetic Retinopathy Study • DSME, diabetes self-management education • DSMT, diabetes self-management training • ECG, electrocardiogram • ESRD, end-stage renal disease • ETDRS, Early Treatment Diabetic Retinopathy Study • FDA, Food and Drug Administration • FPG, fasting plasma glucose • GDM, gestational diabetes mellitus • GFR, glomerular filtration rate • HRC, high-risk characteristic • ICU, intensive care unit • IFG, impaired fasting glucose • IGT, impaired glucose tolerance • MNT, medical nutrition therapy • NPDR, nonproliferative diabetic retinopathy • OGTT, oral glucose tolerance test • PAD, peripheral arterial disease • PDR, proliferative diabetic retinopathy • PPG, postprandial plasma glucose • RDA, recommended dietary allowance • SMBG, self-monitoring of blood glucose • TZD, thiazolidinedione

Diabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetes care is complex and requires that many issues, beyond glycemic control, be addressed. A large body of evidence exists that supports a range of interventions to improve diabetes outcomes.

These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care. While individual preferences, comorbidities, and other patient factors may require modification of goals, targets that are desirable for most patients with diabetes are provided. These standards are not intended to preclude more extensive evaluation and management of the patient by other specialists as needed.

The recommendations included are diagnostic and therapeutic actions that are known or believed to favorably affect health outcomes of patients with diabetes. A grading system (Table 1), developed by the American Diabetes Association (ADA) and modeled after existing methods, was utilized to clarify and codify the evidence that forms the basis for the recommendations. The level of evidence that supports each recommendation is listed after each recommendation using the letters A, B, C, or E.

A. Classification

In 1997, the ADA issued new diagnostic and classification criteria; in 2003, modifications were made regarding the diagnosis of impaired fasting glucose (IFG). The classification of diabetes includes four clinical classes:

• Type 1 diabetes (results from ß-cell destruction, usually leading to absolute insulin deficiency).
• Type 2 diabetes (results from a progressive insulin secretory defect on the background of insulin resistance).
• Other specific types of diabetes due to other causes, e.g., genetic defects in ß-cell function, genetic defects in insulin action, diseases of the exocrine pancreas (such as cystic fibrosis), and drug or chemical induced (such as in the treatment of AIDS or after organ transplantation).
• Gestational diabetes mellitus (GDM) (diagnosed during pregnancy).

B. Diagnosis

Recommendations

• The FPG is the preferred test to diagnose diabetes in children and nonpregnant adults. (E)
• The use of the A1C for the diagnosis of diabetes is not recommended at this time. (E)

Criteria for the diagnosis of diabetes in nonpregnant adults are shown in Table 2. Three ways to diagnose diabetes are available, and each must be confirmed on a subsequent day unless unequivocal symptoms of hyperglycemia are present. Although the 75-g oral glucose tolerance test (OGTT) is more sensitive and modestly more specific than fasting plasma glucose (FPG) to diagnose diabetes, it is poorly reproducible and rarely performed in practice. Because of ease of use, acceptability to patients, and lower cost, the FPG is the preferred diagnostic test. It should be noted that the vast majority of people who meet diagnostic criteria for diabetes by OGTT, but not by FPG, will have an A1C value <7.0%. The use of the A1C for the diagnosis of diabetes is not recommended at this time.

Table 2— Criteria for the diagnosis of diabetes

Hyperglycemia not sufficient to meet the diagnostic criteria for diabetes is categorized as either IFG or impaired glucose tolerance (IGT), depending on whether it is identified through a FPG or an OGTT:

• IFG = FPG 100 mg/dl (5.6 mmol/l) to 125 mg/dl (6.9 mmol/l)
• IGT = 2-h plasma glucose 140 mg/dl (7.8 mmol/l) to 199 mg/dl (11.0 mmol/l)

Recently, IFG and IGT have been officially termed "pre-diabetes." Both categories, IFG and IGT, are risk factors for future diabetes and cardiovascular disease (CVD).

In the absence of unequivocal hyperglycemia, these criteria should be confirmed by repeat testing on a different day. The OGTT is not recommended for routine clinical use but may be required in the evaluation of patients with IFG (see text) or when diabetes is still suspected despite a normal FPG, as with the postpartum evaluation of women with GDM.

Recommendations

• Screening to detect pre-diabetes (IFG or IGT) and diabetes should be considered in individuals 45 years of age, particularly in those with a BMI 25 kg/m2. Screening should also be considered for people who are <45 years of age and are overweight if they have another risk factor for diabetes (Table 3). Repeat testing should be carried out at 3-year intervals. (E)
• Screen for pre-diabetes and diabetes in high-risk, asymptomatic, undiagnosed adults and children within the health care setting. (E)
• To screen for diabetes/pre-diabetes, either an FPG test or 2-h OGTT (75-g glucose load) or both are appropriate. (B)
• An OGTT may be considered in patients with IFG to better define the risk of diabetes. (E)

Table 3— Criteria for testing for diabetes in asymptomatic adult individuals

* May not be correct for all ethnic groups. PCOS, polycystic ovary syndrome.

There is a major distinction between diagnostic testing and screening. Both utilize the same clinical tests, which should be done within the context of the health care setting. When an individual exhibits symptoms or signs of the disease, diagnostic tests are performed, and such tests do not represent screening. The purpose of screening is to identify asymptomatic individuals who are likely to have diabetes or pre-diabetes. Separate diagnostic tests using standard criteria are required after positive screening tests to establish a definitive diagnosis as described above.

Type 1 diabetes

Generally, people with type 1 diabetes present with acute symptoms of diabetes and markedly elevated blood glucose levels. Because of the acute onset of symptoms, most cases of type 1 diabetes are detected soon after symptoms develop. Widespread clinical testing of asymptomatic individuals for the presence of autoantibodies related to type 1 diabetes cannot be recommended at this time as a means to identify individuals at risk. Reasons for this include the following:

1. cutoff values for some of the immune marker assays have not been completely established in clinical settings;
2. there is no consensus as to what action should be taken when a positive autoantibody test result is obtained; and
3. because the incidence of type 1 diabetes is low, testing of healthy children will identify only a very small number (<0.5%) who at that moment may be "pre-diabetic." Clinical studies are being conducted to test various methods of preventing type 1 diabetes in high-risk individuals (e.g., siblings of type 1 diabetic patients). These studies may uncover an effective means of preventing type 1 diabetes, in which case targeted screening may be appropriate in the future.

Type 2 diabetes

Type 2 diabetes is frequently not diagnosed until complications appear, and approximately one-third of all people with diabetes may be undiagnosed. Individuals at high risk should be screened for diabetes and pre-diabetes. Criteria for testing for diabetes in asymptomatic, undiagnosed adults are listed in Table 3. The effectiveness of early diagnosis through screening of asymptomatic individuals has not been determined.

Screening should be carried out within the health care setting. Either an FPG test or 2-h OGTT (75-g glucose load) is appropriate. The 2-h OGTT identifies people with IGT, and thus, more people who are at increased risk for the development of diabetes and CVD. It should be noted that the two tests do not necessarily detect the same individuals. It is important to recognize that although the efficacy of interventions for primary prevention of type 2 diabetes have been demonstrated among individuals with IGT, such data among individuals with IFG (who do not also have IGT) are not available. The FPG test is more convenient to patients, more reproducible, less costly, and easier to administer than the 2-h OGTT. Therefore, the recommended initial screening test for nonpregnant adults is the FPG. An OGTT may be considered in patients with IFG to better define the risk of diabetes. The incidence of type 2 diabetes in children and adolescents has increased dramatically in the last decade. Consistent with screening recommendations for adults, only children and youth at increased risk for the presence or the development of type 2 diabetes should be tested (Table 4).

Table 4— Testing for type 2 diabetes in children

Criteria:

• Overweight (BMI >85th percentile for age and sex, weight for height >85th percentile, or weight >120% of ideal for height)

    Plus any two of the following risk factors:

• Family history of type 2 diabetes in first- or second-degree relative
• Race/ethnicity (Native American, African American, Latino, Asian American, Pacific Islander)
• Signs of insulin resistance or conditions associated with insulin resistance (acanthosis nigricans, hypertension, dyslipidemia, or PCOS)
• Maternal history of diabetes or GDM

    Age of initiation: age 10 years or at onset of puberty, if puberty occurs at a younger age
    Frequency: every 2 years
    Test: FPG preferred

Clinical judgment should be used to test for diabetes in high-risk patients who do not meet these criteria. PCOS, polycystic ovary syndrome.

The effectiveness of screening may also depend on the setting in which it is performed. In general, community screening outside a health care setting may be less effective because of the failure of people with a positive screening test to seek and obtain appropriate follow-up testing and care or, conversely, to ensure appropriate repeat testing for individuals who screen negative. That is, screening outside of clinical settings may yield abnormal tests that are never discussed with a primary care provider, low compliance with treatment recommendations, and a very uncertain impact on long-term health. Community screening may also be poorly targeted, i.e., it may fail to reach the groups most at risk and inappropriately test those at low risk (the worried well) or even those already diagnosed.

On the basis of expert opinion, screening should be considered by health care providers at 3-year intervals beginning at age 45, particularly in those with BMI 25 kg/m2. The rationale for this interval is that false negatives will be repeated before substantial time elapses, and there is little likelihood of an individual developing any of the complications of diabetes to a significant degree within 3 years of a negative screening test result. Testing should be considered at a younger age or be carried out more frequently in individuals who are overweight and have one or more of the other risk factors for type 2 diabetes.

Recommendations

• Screen for diabetes in pregnancy using risk factor analysis and, if appropriate, use of an OGTT. (C)
• Women with GDM should be screened for diabetes 6–12 weeks postpartum and should be followed up with subsequent screening for the development of diabetes or pre-diabetes. (E)

Risk assessment for GDM should be undertaken at the first prenatal visit. Women with clinical characteristics consistent with a high risk for GDM (those with marked obesity, personal history of GDM, glycosuria, or a strong family history of diabetes) should undergo glucose testing as soon as possible. An FPG 126 mg/dl or a casual plasma glucose 200 mg/dl meets the threshold for the diagnosis of diabetes and needs to be confirmed on a subsequent day unless unequivocal symptoms of hyperglycemia are present. High-risk women not found to have GDM at the initial screening and average-risk women should be tested between 24 and 28 weeks of gestation. Testing should follow one of two approaches:

• One-step approach: perform a diagnostic 100-g OGTT
• Two-step approach: perform an initial screening by measuring the plasma or serum glucose concentration 1 h after a 50-g oral glucose load (glucose challenge test) and perform a diagnostic 100-g OGTT on that subset of women exceeding the glucose threshold value on the glucose challenge test. When the two-step approach is used, a glucose threshold value 140 mg/dl identifies 80% of women with GDM, and the yield is further increased to 90% by using a cutoff of 130 mg/dl.

Diagnostic criteria for the 100-g OGTT are as follows: 95 mg/dl fasting, 180 mg/dl at 1 h, 155 mg/dl at 2 h, and 140 mg/dl at 3 h. Two or more of the plasma glucose values must be met or exceeded for a positive diagnosis. The test should be done in the morning after an overnight fast of 8–14 h. The diagnosis can be made using a 75-g glucose load, but that test is not as well validated for detection of at-risk infants or mothers as the 100-g OGTT.

Low-risk status requires no glucose testing, but this category is limited to those women meeting all of the following characteristics:

• Age <25 years.
• Weight normal before pregnancy.
• Member of an ethnic group with a low prevalence of GDM.
• No known diabetes in first-degree relatives.
• No history of abnormal glucose tolerance.
• No history of poor obstetric outcome.

Recommendations

• Individuals at high risk for developing diabetes need to become aware of the benefits of modest weight loss and participating in regular physical activity. (A)
• Patients with IGT should be given counseling on weight loss as well as instruction for increasing physical activity. (A)
• Patients with IFG should be given counseling on weight loss as well as instruction for increasing physical activity. (E)
• Follow-up counseling appears important for success. (B)
• Monitoring for the development of diabetes in those with pre-diabetes should be performed every 1–2 years. (E)
• Close attention should be given to, and appropriate treatment given for, other CVD risk factors (e.g., tobacco use, hypertension, dyslipidemia). (A)
• Drug therapy should not be routinely used to prevent diabetes until more information is known about its cost-effectiveness. (E)

Studies have been initiated in the last decade to determine the feasibility and benefit of various strategies to prevent or delay the onset of type 2 diabetes. Five well-designed randomized controlled trials have been reported. The strategies shown to be effective in preventing diabetes relied on lifestyle modification or glucose-lowering drugs that have been approved for treating diabetes.

In the Finnish study, middle-aged obese subjects with IGT were randomized to receive either brief diet and exercise counseling (control group) or intensive individualized instruction on weight reduction, food intake, and guidance on increasing physical activity (intervention group). After an average follow-up of 3.2 years, there was a 58% relative reduction in the incidence of diabetes in the intervention group compared with the control subjects.

In the Diabetes Prevention Program (DPP), enrolled subjects were slightly younger and more obese but had nearly identical glucose intolerance compared with subjects in the Finnish study. About 45% of the participants were from minority groups (e.g., African American, Hispanic), and 20% were 60 years of age. Subjects were randomized to one of three intervention groups, which included the intensive nutrition and exercise counseling ("lifestyle") group or either of two masked medication treatment groups: the biguanide metformin group or the placebo group. The latter interventions were combined with standard diet and exercise recommendations. After an average follow-up of 2.8 years, a 58% relative reduction in the progression to diabetes was observed in the lifestyle group and a 31% relative reduction in the progression of diabetes was observed in the metformin group compared with control subjects. On average, 50% of the lifestyle group achieved the goal of 7% weight reduction and 74% maintained at least 150 min/week of moderately intense activity. In the troglitazone arm of the DPP (discontinued after a mean of 0.9 years when the drug was withdrawn from the market), troglitazone markedly reduced the incidence of diabetes during the period the drug was given.

In the Da Qing Study, men and women from health care clinics in the city of Da Qing, China, were screened with OGTT, and those with IGT were randomized by clinic to a control group or to one of three active treatment groups: diet only, exercise only, or diet plus exercise. Subjects were reexamined biannually, and after an average of 6 years’ follow-up, the diet, exercise, and diet plus exercise interventions were associated with 31, 46, and 42% reductions in risk of developing type 2 diabetes, respectively.

Three other studies, each using a different class of glucose-lowering agent, have shown a reduction in progression to diabetes with pharmacological intervention. In the Troglitazone in Prevention of Diabetes (TRIPOD) study, Hispanic women with previous GDM were randomized to receive either placebo or troglitazone (a drug now withdrawn from commercial sale in the U.S. but belonging to the thiazolidinedione [TZD] class). After a median follow-up of 30 months, troglitazone treatment was associated with a 56% relative reduction in progression to diabetes. In the STOP-IDDM trial, participants with IGT were randomized in a double-blind fashion to receive either the -glucosidase inhibitor acarbose or a placebo. After a mean follow-up of 3.3 years, a 25% relative risk reduction in progression to diabetes, based on one OGTT, was observed in the acarbose-treated group compared with the placebo group. If this diagnosis was confirmed by a second OGTT, a 36% relative risk reduction was observed in the acarbose group compared with the placebo group.

Finally, in the XENical in the prevention of Diabetes in Obese Subjects (XENDOS) study, orlistat was examined for its ability to delay type 2 diabetes when added to lifestyle change in a group with BMI 30 kg/m2 with or without IGT. After 4 years of treatment, the effect of orlistat addition corresponded to a 45% risk reduction in the IGT group, with no effect observed in those without IGT.

Our knowledge of the early stages of hyperglycemia that portend the diagnosis of diabetes, and the recent success of major intervention trials, clearly show that individuals at high risk can be identified and diabetes delayed, if not prevented. The cost-effectiveness of intervention strategies is unclear, but the huge burden resulting from the complications of diabetes and the potential ancillary benefits of some of the interventions suggest that an effort to prevent diabetes is worthwhile.

Lifestyle modification

In well-controlled studies that included a lifestyle intervention arm, substantial efforts were necessary to achieve only modest changes in weight and exercise, but those changes were sufficient to achieve an important reduction in the incidence of diabetes. In the Finnish Diabetes Prevention Study, weight loss averaged 9.2 lb at 1 year, 7.7 lb after 2 years, and 4.6 lb after 5 years; "moderate exercise," such as brisk walking, for 30 min/day was suggested. In the Finnish study, there was a direct relationship between adherence with the lifestyle intervention and the reduced incidence of diabetes.

In the DPP, the lifestyle group lost 12 lb at 2 years and 9 lb at 3 years (mean weight loss for the study duration was 12 lb or 6% of initial body weight). In both of these studies, most of the participants were obese (BMI >30 kg/m2).

A low-fat (<25% fat) intake was recommended; if reducing fat did not produce weight loss to goal, calorie restriction was also recommended. Participants weighing 120–174 lb (54–78 kg) at baseline were instructed to follow a 1,200-kcal/day diet (33 g fat), those 175–219 lb (79–99 kg) were instructed to follow a 1,500-kcal/day diet (42 g fat), those 220–249 lb (100–113 kg) were instructed to follow an 1,800-kcal/day diet (50 g fat), and those >250 lb (114 kg) were instructed to follow a 2,000-kcal/day diet (55 g fat).

Pharmacological interventions

Three diabetes prevention trials used pharmacological therapy, and all have reported a significant lowering of the incidence of diabetes. The biguanide metformin reduced the risk of diabetes by 31% in the DPP, the -glucosidase inhibitor acarbose reduced the risk by 32% in the STOP-IDDM trial, and the TZD troglitazone reduced the risk by 56% in the TRIPOD study.

In the DPP, metformin was about half as effective as diet and exercise in delaying the onset of diabetes overall, but it was nearly ineffective in older individuals ( 60 years of age) or in those who were less overweight (BMI <30 kg/m2). Conversely, metformin was as effective as lifestyle modification in individuals aged 24–44 years or in those with a BMI 35 kg/m2. Thus, the population of people in whom treatment with metformin has equal benefit to that of a lifestyle intervention is only a small subset of those who are likely to have pre-diabetes (IFG or IGT).

There are also data to suggest that blockade of the renin-angiotensin system may lower the risk of developing diabetes, but more studies are necessary before these drugs can be recommended for preventing diabetes.

Lifestyle or medication?

The DPP is the only study in which a comparison of the two was made, and lifestyle modification was nearly twice as effective in preventing diabetes (58 vs. 31% relative reductions, respectively). The greater benefit of weight loss and physical activity strongly suggests that lifestyle modification should be the first choice to prevent or delay diabetes. Modest weight loss (5–10% of body weight) and modest physical activity (30 min daily) are the recommended goals. Because this intervention not only has been shown to prevent or delay diabetes, but also has a variety of other benefits, health care providers should urge all overweight or sedentary individuals to adopt these changes, and such recommendations should be made at every opportunity.

When all factors are considered, there is insufficient evidence to support the use of drug therapy as a substitute for, or routinely used in addition to, lifestyle modification to prevent diabetes. Public health messages, health care professionals, and health care systems should all encourage behavior changes to achieve a healthy lifestyle. Further research is necessary to understand better how to facilitate effective and efficient programs for the primary prevention of type 2 diabetes.

A. Initial evaluation

A complete medical evaluation should be performed to classify the patient, detect the presence or absence of diabetes complications, assist in formulating a management plan, and provide a basis for continuing care. If the diagnosis of diabetes has already been made, the evaluation should review the previous treatment and the past and present degrees of glycemic control. Laboratory tests appropriate to the evaluation of each patient’s general medical condition should be performed. A focus on the components of comprehensive care (Table 5) will assist the health care team to ensure optimal management of the patient with diabetes.

Table 5— Components of the comprehensive diabetes evaluation

Medical history

• Symptoms, results of laboratory tests, and special examination results related to the diagnosis of diabetes
• Prior A1C records
• Eating patterns, nutritional status, and weight history; growth and development in children and adolescents
• Details of previous treatment programs, including nutrition and diabetes self-management education, attitudes, and health beliefs
• Current treatment of diabetes, including medications, meal plan, and results of glucose monitoring and patients’ use of data
• Exercise history
• Frequency, severity, and cause of acute complications such as ketoacidosis and hypoglycemia
• Prior or current infections, particularly skin, foot, dental, and genitourinary infections
• Symptoms and treatment of chronic eye; kidney; nerve; genitourinary (including sexual), bladder, and gastrointestinal function (including symptoms of celiac disease in type 1 diabetic patients); heart; peripheral vascular; foot; and cerebrovascular complications associated with diabetes
• Other medications that may affect blood glucose levels
• Risk factors for atherosclerosis: smoking, hypertension, obesity, dyslipidemia, and family history
• History and treatment of other conditions, including endocrine and eating disorders
• Assessment for mood disorder
• Family history of diabetes and other endocrine disorders
• Lifestyle, cultural, psychosocial, educational, and economic factors that might influence the management of diabetes
• Tobacco, alcohol, and/or controlled substance use
• Contraception and reproductive and sexual history

Physical examination

• Height and weight measurement (and comparison to norms in children and adolescents)
• Sexual maturation staging (during pubertal period)
• Blood pressure determination, including orthostatic measurements when indicated, and comparison to age-related norms
• Fundoscopic examination
• Oral examination
• Thyroid palpation
• Cardiac examination
• Abdominal examination (e.g., for hepatomegaly)
• Evaluation of pulses by palpation and with auscultation
• Hand/finger examination
• Foot examination
• Skin examination (for acanthosis nigricans and insulin-injection sites)
• Neurological examination
• Signs of diseases that can cause secondary diabetes (e.g., hemochromatosis, pancreatic disease)

Laboratory evaluation

• A1C
• Fasting lipid profile, including total cholesterol, HDL cholesterol, triglycerides, and LDL cholesterol, liver function tests with further evaluation for fatty liver or hepatitis if abnormal
• Test for microalbuminuria in type 1 diabetic patients who have had diabetes for at least 5 years and in all patients with type 2 diabetes; some advocate beginning screening of pubertal children before 5 years of diabetes
• Serum creatinine and calculated GFR in adults (check creatinine in children if proteinuria is present)
• Thyroid-stimulating hormone (TSH) in all type 1 diabetic patients; in type 2 if clinically indicated
• Electrocardiogram in adults, if clinically indicated
• Urinalysis for ketones, protein, sediment

Referrals

• Eye exam, if indicated
• Family planning for women of reproductive age
• MNT, as indicated
• Diabetes educator, if not provided by physician or practice staff
• Behavioral specialist, as indicated
• Foot specialist, as indicated
• Other specialties and services as appropriate

B. Management

People with diabetes should receive medical care from a physician-coordinated team. Such teams may include, but are not limited to, physicians, nurse practitioners, physician’s assistants, nurses, dietitians, pharmacists, and mental health professionals with expertise and a special interest in diabetes. It is essential in this collaborative and integrated team approach that individuals with diabetes assume an active role in their care.

The management plan should be formulated as an individualized therapeutic alliance among the patient and family, the physician, and other members of the health care team. Any plan should recognize diabetes self-management education (DSME) as an integral component of care. In developing the plan, consideration should be given to the patient’s age, school or work schedule and conditions, physical activity, eating patterns, social situation and personality, cultural factors, and presence of complications of diabetes or other medical conditions. A variety of strategies and techniques should be used to provide adequate education and development of problem-solving skills in the various aspects of diabetes management. Implementation of the management plan requires that each aspect is understood and agreed on by the patient and the care providers and that the goals and treatment plan are reasonable.

C. Glycemic control

1. Assessment of glycemic control

Techniques are available for health providers and patients to assess the effectiveness of the management plan on glycemic control.

a. Self-monitoring of blood glucose

Recommendations

• Clinical trials using insulin that have demonstrated the value of tight glycemic control have used self-monitoring of blood glucose (SMBG) as an integral part of the management strategy. (A)
• SMBG should be carried out three or more times daily for patients using multiple insulin injections. (A)
• For patients using less frequent insulin injections or oral agents or medical nutrition therapy (MNT) alone, SMBG is useful in achieving glycemic goals. (E)
• To achieve postprandial glucose targets, postprandial SMBG may be appropriate. (E)
• Instruct the patient in SMBG and routinely evaluate the patient’s technique and ability to use data to adjust therapy. (E)

The ADA’s consensus statements on SMBG provide a comprehensive review of the subject. Major clinical trials assessing the impact of glycemic control on diabetes complications have included SMBG as part of multifactorial interventions, suggesting that SMBG is a component of effective therapy. SMBG allows patients to evaluate their individual response to therapy and assess whether glycemic targets are being achieved. Results of SMBG can be useful in preventing hypoglycemia and adjusting medications, MNT, and physical activity.

The frequency and timing of SMBG should be dictated by the particular needs and goals of the patients. Daily SMBG is especially important for patients treated with insulin to monitor for and prevent asymptomatic hypoglycemia and hyperglycemia. For most patients with type 1 diabetes and pregnant women taking insulin, SMBG is recommended three or more times daily. The optimal frequency and timing of SMBG for patients with type 2 diabetes on oral agent therapy is not known but should be sufficient to facilitate reaching glucose goals. Patients with type 2 diabetes on insulin typically need to perform SMBG more frequently than those not using insulin. When adding to or modifying therapy, type 1 and type 2 diabetic patients should test more often than usual. The role of SMBG in stable diet-treated patients with type 2 diabetes is not known.

Because the accuracy of SMBG is instrument and user dependent, it is important for health care providers to evaluate each patient’s monitoring technique, both initially and at regular intervals thereafter. In addition, optimal use of SMBG requires proper interpretation of the data. Patients should be taught how to use the data to adjust food intake, exercise, or pharmacological therapy to achieve specific glycemic goals. Health professionals should evaluate at regular intervals the patient’s ability to use SMBG data to guide treatment.

b. A1C

Recommendations

• Perform the A1C test at least two times a year in patients who are meeting treatment goals (and who have stable glycemic control). (E)
• Perform the A1C test quarterly in patients whose therapy has changed or who are not meeting glycemic goals. (E)
• Use of point-of-care testing for A1C allows for timely decisions on therapy changes, when needed. (E)

By performing an A1C test, health providers can measure a patient’s average glycemia over the preceding 2–3 months and, thus, assess treatment efficacy. A1C testing should be performed routinely in all patients with diabetes, first to document the degree of glycemic control at initial assessment and then as part of continuing care. Since the A1C test reflects mean glycemia over the preceding 2–3 months, measurement approximately every 3 months is required to determine whether a patient’s metabolic control has been reached and maintained within the target range. Thus, regular performance of the A1C test permits detection of departures from the target (Table 6) in a timely fashion. For any individual patient, the frequency of A1C testing should be dependent on the clinical situation, the treatment regimen used, and the judgment of the clinician.

Table 6— Summary of recommendations for adults with diabetes

Key concepts in setting glycemic goals:

• A1C is the primary target for glycemic control
• Goals should be individualized
• Certain populations (children, pregnant women, and elderly) require special considerations
• More stringent glycemic goals (i.e., a normal A1C, <6%) may further reduce complications at the cost of increased risk of hypoglycemia
• Less intensive glycemic goals may be indicated in patients with severe or frequent hypoglycemia
• Postprandial glucose may be targeted if A1C goals are not met despite reaching preprandial glucose goals

* Referenced to a nondiabetic range of 4.0–6.0% using a DCCT-based assay.
** Postprandial glucose measurements should be made 1–2 h after the beginning of the meal, generally peak levels in patients with diabetes.
^ Current NCEP/ATP III guidelines suggest that in patients with triglycerides 200 mg/dl, the "non-HDL cholesterol" (total cholesterol minus HDL) be utilized. The goal is 130 mg/dl (34).
$ For women, it has been suggested that the HDL goal be increased by 10 mg/dl.

The A1C test is subject to certain limitations. Conditions that affect erythrocyte turnover (hemolysis, blood loss) and hemoglobin variants must be considered, particularly when the A1C result does not correlate with the patient’s clinical situation. The availability of the A1C result at the time that the patient is seen (point of care testing) has been reported to result in the frequency of intensification of therapy and improvement in glycemic control.

Glycemic control is best judged by the combination of the results of the patient’s SMBG testing (as performed) and the current A1C result. The A1C should be used not only to assess the patient’s control over the preceding 2–3 months but also as a check on the accuracy of the meter (or the patient’s self-reported results) and the adequacy of the SMBG testing schedule.