Table 1.

Nonglycemic factors that may influence HbA_1c

Factors that may influence interpretation of HbA1c
1. Physiological (e.g., age, race)
2. Chronic renal failure
3. Iron-deficiency anemia
4. Erythrocyte life span
5. Glycation “phenotypes”
6. Drugs (e.g., dapsone, antiretroviral)
7. Other (e.g., vitamin C, vitamin E)
Factors that may interfere with HbA1c measurement
1. Uremia
2. Hemoglobin variants
3. Drugs (e.g., opiates)
4. Other (e.g., bilirubin, triglyceride, alcohol)