In order to be diagnosed with pre-diabetes or diabetes, you must meet at least one of the three criteria below.
| Non-Diabetes | Pre-Diabetes | Diabetes | |
| Fasting | < 100 mg/dL | 100 - 125 mg/dL | ≥ 126 mg/dL* |
| A1C | ≤ 5.6% | 5.7-6.4% | ≥ 6.5% |
| Random | ≤ 140 mg/dL | 141 - 199 mg/dL | ≥ 200 mg/dL with symptoms of hyperglycemia |
* requires 2 abnormal results
Specific Diagnostic Criteria for Type 1 Diabetes
Type 1 diabetes is an autoimmune disorder where pancreatic β-cell destruction occurs, as compared to Type 2 diabetes which is a metabolic disorder. Type 1 diabetes accounts for less than 10% of all diabetes.
In order to be diagnosed Type 1 diabetes:
- One must have at least one positive autoantibodies of the below list, but having none does not exclude diagnosis:
- Islet Cell Antibodies (ICA)
- Antibodies to Glutamic Acid Decarboxylase (GAD-65)
- Insulin Autoantibodies (IAA)
- Insulinoma-associated-protein-2 Autoantibodies (IA-2A)
- Zinc-transporter 8 Autoantibodies (ZnT8A)
- Clinical symptoms of hyperglycemia
- Meet any of the three criteria for Diabetes as shown above
Oddly enough, people can have one autoantibody positive and never develop type 1 diabetes
Progression to type 1 diabetes is very low (risk) in those who only develop a single autoantibody (15%); whereas, 70% of those who develop multiple autoantibodies progress to type 1 diabetes.
For further information
Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes—2020
Type 1 Diabetes and Autoantibodies: Here’s What You Need to Know
Reference
Reversion of b-Cell Autoimmunity Changes Risk of Type 1 Diabetes: TEDDY Study