From the Guidelines
Type 2 diabetes mellitus is diagnosed when a patient has a hemoglobin A1C ≥6.5%, fasting plasma glucose ≥126 mg/dL, 2-hour plasma glucose ≥200 mg/dL during an oral glucose tolerance test, or random plasma glucose ≥200 mg/dL with classic symptoms of hyperglycemia, as recommended by the most recent guidelines 1.
Diagnostic Criteria
The diagnostic criteria for type 2 diabetes mellitus include:
- Hemoglobin A1C ≥6.5%
- Fasting plasma glucose ≥126 mg/dL
- 2-hour plasma glucose ≥200 mg/dL during an oral glucose tolerance test
- Random plasma glucose ≥200 mg/dL with classic symptoms of hyperglycemia These criteria are based on the guidelines from the American College of Physicians and the American Diabetes Association, as well as other reputable sources 1.
Treatment Guidelines
Treatment for type 2 diabetes mellitus begins with lifestyle modifications, including:
- Weight loss
- Regular physical activity
- A healthy diet If lifestyle modifications are not sufficient to achieve glycemic targets, medication may be necessary. Metformin is the preferred initial medication, with a starting dose of 500 mg once or twice daily, gradually increased to 1000 mg twice daily as tolerated 1. Additional medications that may be considered include:
- SGLT-2 inhibitors (empagliflozin, dapagliflozin)
- GLP-1 receptor agonists (semaglutide, dulaglutide)
- DPP-4 inhibitors (sitagliptin)
- Sulfonylureas (glipizide)
- Thiazolidinediones (pioglitazone)
- Insulin therapy Patients with established cardiovascular disease or high risk should preferentially receive SGLT-2 inhibitors or GLP-1 receptor agonists due to their proven cardiovascular benefits 1.
Monitoring and Follow-up
Regular monitoring includes:
- Quarterly A1C testing until target is reached
- Annual screening for complications (retinopathy, nephropathy, neuropathy)
- Ongoing assessment of cardiovascular risk factors These guidelines target the underlying pathophysiology of type 2 diabetes, which involves insulin resistance and progressive beta-cell dysfunction, to prevent both microvascular and macrovascular complications 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Diagnostic Criteria for Type 2 Diabetes Mellitus
The diagnostic criteria for type 2 diabetes mellitus (DM) include:
- Fasting plasma glucose (FPG) level of 126 mg/dL or greater 2, 3, 4, 5, 6
- A1C level of 6.5% or greater 3, 4, 5, 6
- Random plasma glucose level of 200 mg/dL or greater 3, 5, 6
- A 75-g two-hour oral glucose tolerance test with a plasma glucose level of 200 mg/dL or greater 3, 5, 6
Screening and Diagnosis Guidelines
The guidelines for screening and diagnosis of type 2 DM are as follows:
- The U.S. Preventive Services Task Force recommends screening for abnormal blood glucose and type 2 diabetes in adults 40 to 70 years of age who are overweight or obese, and repeating testing every three years if results are normal 6
- The American Diabetes Association recommends screening for type 2 diabetes annually in patients 45 years and older, or in patients younger than 45 years with major risk factors 6
- Results should be confirmed with repeat testing on a subsequent day; however, a single random plasma glucose level of 200 mg/dL or greater with typical signs and symptoms of hyperglycemia likely indicates diabetes 6
Impaired Fasting Glucose and Impaired Glucose Tolerance
The guidelines also include the following categories:
- Impaired fasting glucose (IFG): FPG level of 110-125 mg/dL 2, 4, 5
- Impaired glucose tolerance (IGT): 2-hour plasma glucose level of 140-199 mg/dL during an oral glucose tolerance test 4, 5
- Borderline type: includes those who are neither diabetic nor normal types, and corresponds to the sum of IFG and IGT when an oral glucose tolerance test is performed 5
Gestational Diabetes Mellitus
The diagnosis of gestational diabetes mellitus (GDM) is made when two or more values during a 75-g oral glucose tolerance test are higher than the following cutoff levels: FPG > or = 100 mg/dL, 1-hour plasma glucose > or = 180 mg/dL, and 2-hour plasma glucose > or = 150 mg/dL 5