A1C Screening Guidelines for Adolescents and Adults

Age-Based Screening Recommendations

The American Diabetes Association recommends that screening for type 2 diabetes should begin at age 45 years in adults without any risk factors 1, 2
For adults aged 40-70 years with BMI ≥25 kg/m², A1C testing is recommended 2

Risk-based screening should be considered after the onset of puberty or ≥10 years of age (whichever occurs earlier) only in youth with overweight (BMI ≥85th percentile) or obesity (BMI ≥95th percentile) AND one or more additional risk factors for diabetes 3, 4, 5
The American Diabetes Association identifies additional risk factors that would warrant screening, including having a first-degree relative with diabetes 1
High-risk race/ethnicity (African American, Latino, Native American, Asian American, Pacific Islander) is also a risk factor that would warrant screening 1
Maternal history of gestational diabetes is a risk factor that would warrant screening 4
Signs of insulin resistance (such as high blood pressure, high cholesterol, or polycystic ovary syndrome) are risk factors that would warrant screening 1
Physical inactivity is a risk factor that would warrant screening 1

If initial screening is normal, repeat testing should occur at minimum 2-3 year intervals, not annually 4, 5
The U.S. diabetes guidelines suggest that the dramatic increase in type 2 diabetes prevalence in youth primarily affects those with obesity and other risk factors, not healthy-weight adolescents without risk factors 4, 5
The American Diabetes Association recommends against universal screening of all adolescents, as this leads to unnecessary testing and potential false positives 2
A1C may underestimate blood sugar levels in certain populations and has limited validation data in pediatric populations, though it remains the recommended screening test when indicated 6, 7