ADA guidelines are published every January. Please find below the 2017 recommendations on how to properly categorize various types of diabetes mellitus.
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Diabetes Care
ADA Guidelines
January 2017
ADA CLASSIFICATION:
Diabetes can be classified into the following general categories:
- Type 1 diabetes (due to autoimmune β-cell destruction, usually leading to absolute insulin deficiency)
- Type 2 diabetes (due to a progressive loss of β-cell insulin secretion frequently on the background of insulin resistance)
- Gestational diabetes mellitus (diabetes diagnosed in the 2nd or 3rd trimester of pregnancy that was not clearly overt diabetes prior to gestation)
- Specific types of diabetes due to other causes, e.g., monogenic diabetes syndromes (such as neonatal diabetes and maturity-onset diabetes of the young [MODY]), diseases of the exocrine pancreas (such as cystic fibrosis), and drug- or chemical-induced diabetes (such as with glucocorticoid use, in the treatment of HIV/AIDS, or after organ transplantation)
Recommendations
PREDIABETES (similar to DM2)
- Testing for prediabetes and risk for future diabetes in asymptomatic people should be considered in adults of any age who are overweight or obese (BMI ≥25 or ≥23 in Asian Americans) and who have one or more additional risk factors for diabetes.
- For all people, testing should begin at age 45 years.
- If tests are normal, repeat testing carried out at a minimum of 3-year intervals is reasonable.
- To test for prediabetes, fasting plasma glucose, 2-h plasma glucose after 75-g oral glucose tolerance test, and A1C are equally appropriate.
- Testing for prediabetes should be considered in children and adolescents who are overweight or obese and who have two or more additional risk factors for diabetes.
POST-TRANSPLANTATION DIABETES MELLITUS
- Patients should be screened after organ transplantation for hyperglycemia, with a formal diagnosis of posttransplantation diabetes mellitus being best made once a patient is stable on an immunosuppressive regimen and in the absence of an acute infection.
- The oral glucose tolerance test is the preferred test to make a diagnosis of posttransplantation diabetes mellitus.
CYSTIC FIBROSIS–RELATED DIABETES
- Annual screening for cystic fibrosis–related diabetes with oral glucose tolerance test should begin by age 10 years in all patients with cystic fibrosis not previously diagnosed with cystic fibrosis–related diabetes.
- A1C as a screening test for cystic fibrosis–related diabetes is not recommended.
- Patients with cystic fibrosis–related diabetes should be treated with insulin to attain individualized glycemic goals.
- Beginning 5 years after the diagnosis of cystic fibrosis–related diabetes, annual monitoring for complications of diabetes is recommended.
POST-TRANSPLANTATION DIABETES MELLITUS
- Patients should be screened after organ transplantation for hyperglycemia, with a formal diagnosis of posttransplantation diabetes mellitus being best made once a patient is stable on an immunosuppressive regimen and in the absence of an acute infection.
- The oral glucose tolerance test is the preferred test to make a diagnosis of posttransplantation diabetes mellitus.
MONOGENIC DIABETES SYNDROMES
- All children diagnosed with diabetes in the first 6 months of life should have immediate genetic testing for neonatal diabetes.
- Children and adults, diagnosed in early adulthood, who have diabetes not characteristic of type 1 or type 2 diabetes that occurs in successive generations (suggestive of an autosomal dominant pattern of inheritance) should have genetic testing for maturity-onset diabetes of the young.
- In both instances, consultation with a center specializing in diabetes genetics is recommended to understand the significance of these mutations and how best to approach further evaluation, treatment, and genetic counseling.
CYSTIC FIBROSIS–RELATED DIABETES
- Annual screening for cystic fibrosis–related diabetes with oral glucose tolerance test should begin by age 10 years in all patients with cystic fibrosis not previously diagnosed with cystic fibrosis–related diabetes.
- A1C as a screening test for cystic fibrosis–related diabetes is not recommended.
- Patients with cystic fibrosis–related diabetes should be treated with insulin to attain individualized glycemic goals.
- Beginning 5 years after the diagnosis of cystic fibrosis–related diabetes, annual monitoring for complications of diabetes is recommended.
POST-TRANSPLANTATION DIABETES MELLITUS
- Patients should be screened after organ transplantation for hyperglycemia, with a formal diagnosis of posttransplantation diabetes mellitus being best made once a patient is stable on an immunosuppressive regimen and in the absence of an acute infection.
- The oral glucose tolerance test is the preferred test to make a diagnosis of posttransplantation diabetes mellitus.
GESTATIONAL DM
- Test for undiagnosed diabetes at the first prenatal visit in those with risk factors, using standard diagnostic criteria.
- Test for gestational diabetes mellitus at 24–28 weeks [at the start of 3rd trimester] of gestation in pregnant women not previously known to have diabetes.
- Test women with gestational diabetes mellitus for persistent diabetes at 4–12 weeks’ postpartum, using the oral glucose tolerance test and clinically appropriate nonpregnancy diagnostic criteria.
- Women with a history of gestational diabetes mellitus should have lifelong screening for the development of diabetes or prediabetes at least every 3 years.
- Women with a history of gestational diabetes mellitus found to have prediabetes should receive intensive lifestyle interventions or metformin to prevent diabetes.
MONOGENIC DIABETES SYNDROMES
- All children diagnosed with diabetes in the first 6 months of life should have immediate genetic testing for neonatal diabetes.
- Children and adults, diagnosed in early adulthood, who have diabetes not characteristic of type 1 or type 2 diabetes that occurs in successive generations (suggestive of an autosomal dominant pattern of inheritance) should have genetic testing for maturity-onset diabetes of the young.
- In both instances, consultation with a center specializing in diabetes genetics is recommended to understand the significance of these mutations and how best to approach further evaluation, treatment, and genetic counseling.
CYSTIC FIBROSIS–RELATED DIABETES
- Annual screening for cystic fibrosis–related diabetes with oral glucose tolerance test should begin by age 10 years in all patients with cystic fibrosis not previously diagnosed with cystic fibrosis–related diabetes.
- A1C as a screening test for cystic fibrosis–related diabetes is not recommended.
- Patients with cystic fibrosis–related diabetes should be treated with insulin to attain individualized glycemic goals.
- Beginning 5 years after the diagnosis of cystic fibrosis–related diabetes, annual monitoring for complications of diabetes is recommended.
POST-TRANSPLANTATION DIABETES MELLITUS
- Patients should be screened after organ transplantation for hyperglycemia, with a formal diagnosis of posttransplantation diabetes mellitus being best made once a patient is stable on an immunosuppressive regimen and in the absence of an acute infection.
- The oral glucose tolerance test is the preferred test to make a diagnosis of posttransplantation diabetes mellitus.
TYPE 2 DIABETES (similar to Pre-DM)
- Testing for type 2 diabetes in asymptomatic people should be considered in adults of any age who are overweight or obese (BMI ≥25 or ≥23 in Asian Americans) and who have one or more additional risk factors for diabetes.
- For all people, testing should begin at age 45 years.
- If tests are normal, repeat testing carried out at a minimum of 3-year intervals is reasonable.
- To test for type 2 diabetes, fasting plasma glucose, 2-h plasma glucose after 75-g oral glucose tolerance test, and A1C are equally appropriate.
- Testing for type 2 diabetes should be considered in children and adolescents who are overweight or obese and who have two or more additional risk factors for diabetes.
GESTATIONAL DM
- Test for undiagnosed diabetes at the first prenatal visit in those with risk factors, using standard diagnostic criteria.
- Test for gestational diabetes mellitus at 24–28 weeks [at the start of 3rd trimester] of gestation in pregnant women not previously known to have diabetes.
- Test women with gestational diabetes mellitus for persistent diabetes at 4–12 weeks’ postpartum, using the oral glucose tolerance test and clinically appropriate nonpregnancy diagnostic criteria.
- Women with a history of gestational diabetes mellitus should have lifelong screening for the development of diabetes or prediabetes at least every 3 years.
- Women with a history of gestational diabetes mellitus found to have prediabetes should receive intensive lifestyle interventions or metformin to prevent diabetes.
MONOGENIC DIABETES SYNDROMES
- All children diagnosed with diabetes in the first 6 months of life should have immediate genetic testing for neonatal diabetes.
- Children and adults, diagnosed in early adulthood, who have diabetes not characteristic of type 1 or type 2 diabetes that occurs in successive generations (suggestive of an autosomal dominant pattern of inheritance) should have genetic testing for maturity-onset diabetes of the young.
- In both instances, consultation with a center specializing in diabetes genetics is recommended to understand the significance of these mutations and how best to approach further evaluation, treatment, and genetic counseling.
CYSTIC FIBROSIS–RELATED DIABETES
- Annual screening for cystic fibrosis–related diabetes with oral glucose tolerance test should begin by age 10 years in all patients with cystic fibrosis not previously diagnosed with cystic fibrosis–related diabetes.
- A1C as a screening test for cystic fibrosis–related diabetes is not recommended.
- Patients with cystic fibrosis–related diabetes should be treated with insulin to attain individualized glycemic goals.
- Beginning 5 years after the diagnosis of cystic fibrosis–related diabetes, annual monitoring for complications of diabetes is recommended.
POST-TRANSPLANTATION DIABETES MELLITUS
- Patients should be screened after organ transplantation for hyperglycemia, with a formal diagnosis of posttransplantation diabetes mellitus being best made once a patient is stable on an immunosuppressive regimen and in the absence of an acute infection.
- The oral glucose tolerance test is the preferred test to make a diagnosis of posttransplantation diabetes mellitus.
TYPE 1 DIABETES
- Blood glucose rather than A1C should be used to diagnose the acute onset of type 1 diabetes in individuals with symptoms of hyperglycemia.
- Screening for type 1 diabetes with a panel of autoantibodies is currently recommended only in the setting of a research trial or in first-degree family members of a proband with type 1 diabetes.
- Persistence of two or more autoantibodies predicts clinical diabetes and may serve as an indication for intervention in the setting of a clinical trial. Outcomes may include reversion of autoantibody status, prevention of glycemic progression within the normal or prediabetes range, prevention of clinical diabetes, or preservation of residual C-peptide secretion.
TYPE 2 DIABETES (similar to Pre-DM)
- Testing for type 2 diabetes in asymptomatic people should be considered in adults of any age who are overweight or obese (BMI ≥25 or ≥23 in Asian Americans) and who have one or more additional risk factors for diabetes.
- For all people, testing should begin at age 45 years.
- If tests are normal, repeat testing carried out at a minimum of 3-year intervals is reasonable.
- To test for type 2 diabetes, fasting plasma glucose, 2-h plasma glucose after 75-g oral glucose tolerance test, and A1C are equally appropriate.
- Testing for type 2 diabetes should be considered in children and adolescents who are overweight or obese and who have two or more additional risk factors for diabetes.
GESTATIONAL DM
- Test for undiagnosed diabetes at the first prenatal visit in those with risk factors, using standard diagnostic criteria.
- Test for gestational diabetes mellitus at 24–28 weeks [at the start of 3rd trimester] of gestation in pregnant women not previously known to have diabetes.
- Test women with gestational diabetes mellitus for persistent diabetes at 4–12 weeks’ postpartum, using the oral glucose tolerance test and clinically appropriate nonpregnancy diagnostic criteria.
- Women with a history of gestational diabetes mellitus should have lifelong screening for the development of diabetes or prediabetes at least every 3 years.
- Women with a history of gestational diabetes mellitus found to have prediabetes should receive intensive lifestyle interventions or metformin to prevent diabetes.
MONOGENIC DIABETES SYNDROMES
- All children diagnosed with diabetes in the first 6 months of life should have immediate genetic testing for neonatal diabetes.
- Children and adults, diagnosed in early adulthood, who have diabetes not characteristic of type 1 or type 2 diabetes that occurs in successive generations (suggestive of an autosomal dominant pattern of inheritance) should have genetic testing for maturity-onset diabetes of the young.
- In both instances, consultation with a center specializing in diabetes genetics is recommended to understand the significance of these mutations and how best to approach further evaluation, treatment, and genetic counseling.
CYSTIC FIBROSIS–RELATED DIABETES
- Annual screening for cystic fibrosis–related diabetes with oral glucose tolerance test should begin by age 10 years in all patients with cystic fibrosis not previously diagnosed with cystic fibrosis–related diabetes.
- A1C as a screening test for cystic fibrosis–related diabetes is not recommended.
- Patients with cystic fibrosis–related diabetes should be treated with insulin to attain individualized glycemic goals.
- Beginning 5 years after the diagnosis of cystic fibrosis–related diabetes, annual monitoring for complications of diabetes is recommended.
POST-TRANSPLANTATION DIABETES MELLITUS
- Patients should be screened after organ transplantation for hyperglycemia, with a formal diagnosis of posttransplantation diabetes mellitus being best made once a patient is stable on an immunosuppressive regimen and in the absence of an acute infection.
- The oral glucose tolerance test is the preferred test to make a diagnosis of posttransplantation diabetes mellitus.