Table 3

Percentage of individuals with prediabetes reporting metformin use by criteria for metformin use

Risk factors for prediabetesn*N% (SE) on metformin
Prediabetes by IFG, IGT, HbA1c, or self-report917,6520.8 (0.8)
Prediabetes based on IGT alone12850.8 (0.8)
Prediabetes based on IFG alone01,5770
Prediabetes based on HbA1c 5.7–6.4% alone183,0650.6 (0.2)
Prediabetes based on HbA1c 6.0–6.4% alone131,4110.9 (0.3)
Self-reported prediabetes alone000
BMI ≥35 kg/m2331,3161.9 (0.5)
IFG and IGT + risk factor§000
IGT + risk factor11901.1 (1.0)
IFG + risk factor01,1780
HbA1c 5.7–6.4% + risk factor132,1010.7 (0.2)
Self-reported prediabetes + risk factor000
IFG and IGT + risk factor + HbA1c 6.0–6.4%01790
  • IFG, impaired fasting glucose; IGT, impaired glucose tolerance.

  • *Represents unweighted n for those treated with metformin.

  • †Represents unweighted n for those treated or not treated with metformin.

  • ‡Represents weighted percentage.

  • §2007 guidelines risk factors: age <60 years, BMI ≥35 kg/m2, family history of diabetes, elevated triglycerides, low HDL cholesterol, hypertension, or HbA1c ≥6%. We defined elevated triglycerides as ≥150 mg/dL and low HDL cholesterol as <40 mg/dL based on Adult Treatment Panel III guidelines (30).

  • ‖2017 guidelines risk factors: age <60 years, BMI ≥35 kg/m2, or history of gestational diabetes mellitus (not available in this data set) and rising HbA1c despite lifestyle intervention (not available in this data set).