How to screen for type 2 diabetes in children?

Screening for Type 2 Diabetes in Children

Risk-based screening for prediabetes and/or type 2 diabetes should be performed in children who are overweight or obese and have additional risk factors, starting at age 10 years or at the onset of puberty, whichever occurs earlier. 1

Who to Screen

Screening should be targeted to high-risk children who meet the following criteria:

1. Primary criterion: Overweight or obesity

   • BMI ≥85th percentile for age and sex (overweight)
   • BMI ≥95th percentile for age and sex (obesity)
   • Weight for height ≥85th percentile
   • Weight ≥120% of ideal for height

2. Plus at least two of these additional risk factors:

   • Family history of type 2 diabetes in first- or second-degree relatives
   • High-risk race/ethnicity (American Indian, African-American, Hispanic, Asian/Pacific Islander)
   • Signs of insulin resistance or conditions associated with insulin resistance:
     • Acanthosis nigricans
     • Hypertension
     • Dyslipidemia
     • Polycystic ovarian syndrome (PCOS) 1

When to Screen

• Initial screening: Age 10 years or at onset of puberty, whichever occurs earlier
• Repeat screening:
  • If initial screen is normal: Every 3 years minimum 1
  • More frequently if BMI is increasing 1

How to Screen

The following tests can be used to screen for prediabetes or diabetes in children:

1. Fasting plasma glucose (FPG) - preferred initial test 1

   • Normal: <100 mg/dL
   • Prediabetes (impaired fasting glucose): 100-125 mg/dL
   • Diabetes: ≥126 mg/dL

2. 2-hour plasma glucose during 75-g oral glucose tolerance test (OGTT)

   • Normal: <140 mg/dL
   • Prediabetes (impaired glucose tolerance): 140-199 mg/dL
   • Diabetes: ≥200 mg/dL

3. A1C

   • Normal: <5.7%
   • Prediabetes: 5.7-6.4%
   • Diabetes: ≥6.5% 1

Important Diagnostic Considerations

• Confirmation testing: In the absence of unequivocal hyperglycemia, results should be confirmed by repeat testing on a different day 1

• Distinguishing between diabetes types: Children with overweight/obesity in whom type 2 diabetes is suspected should have pancreatic autoantibodies tested to exclude autoimmune type 1 diabetes 1

• Test limitations:

  • A1C may have limitations in certain populations and should not be used for diagnosis in children with hemoglobinopathies or suspected type 1 diabetes with acute onset 1
  • OGTT can detect impaired glucose tolerance that may be missed by FPG or A1C but is less convenient and has lower reproducibility 2
  • FPG alone may overdiagnose diabetes in children 1

Diagnostic Challenges

The distinction between type 1 and type 2 diabetes can be difficult in pediatric patients:

• Overweight and obesity are common in children with type 1 diabetes
• Diabetes-associated autoantibodies and ketosis may be present in children with clinical features of type 2 diabetes
• Accurate diagnosis is critical as treatment approaches differ markedly between the two types 1

Pitfalls to Avoid

1. Missing cases by using only one test: Up to 68% of children with dysglycemia may have normal fasting glucose but abnormal 2-hour glucose values 3

2. Relying solely on A1C: While convenient, A1C can be affected by non-glycemic factors and has not been fully validated in the pediatric population 2

3. Failing to consider type 2 diabetes in younger children: Although uncommon, type 2 diabetes has been observed in prepubertal children under 10 years of age 1

4. Not considering screening in high-risk children who don't meet all criteria: Clinical judgment should be used to test for diabetes in high-risk patients who don't meet all formal screening criteria 1

By implementing these evidence-based screening protocols, clinicians can identify children with type 2 diabetes earlier, potentially reducing the risk of long-term complications and improving outcomes related to morbidity, mortality, and quality of life.