Table 1

Baseline characteristics of participants in GRADE

Overall (n = 5,047)*Normal range for laboratory tests
Age at baseline visit (years)57.2 ± 10.0
Age group (years)
 <45619 (12.3)
 45–592,327 (46.1)
 ≥602,101 (41.6)
Male sex3,210 (63.6)
Race
 White3,314 (65.7)
 African American or black1,000 (19.8)
 Asian182 (3.6)
 AI/AN137 (2.7)
 Native Hawaiian or other Pacific Islander28 (0.6)
 Other or more than one race319 (6.3)
 Unknown or not reported67 (1.3)
Ethnicity
 Hispanic/Latino929 (18.4)
 Not Hispanic/Latino4,077 (80.8)
 Unknown/not reported41 (0.8)
Education completed
 <High school364 (7.2)
 High school graduate1,039 (20.6)
 Some college1,463 (29.0)
 ≥College degree2,180 (43.2)
Duration of diabetes (years)4.2 ± 2.8
Duration of diabetes (years), median (IQR)3.8 (1.9, 6.4)
Screening metformin dose (mg/day)1,575.5 ± 525.2
Baseline metformin dose (mg/day)1,944.2 ± 204.5
Family history of any first-degree relatives with diabetes3,522 (69.8)
Medical history
 Heart attack/stroke330 (6.5)
 Retinopathy49 (1.0)
 Neuropathy1,083 (21.5)
 Hypertension3,360 (66.6)
 Elevated blood lipids3,646 (72.2)
Current medications
 Blood pressure medications3,495 (69.2)
 Lipid-lowering medications3,317 (65.7)
  Statin3,209 (63.6)
  Aspirin2,288 (45.3)
 Depression/anxiety medication(s)472/2,502 (18.9)
Smoking status
 Current smoker695 (13.8)
 Former smoker1,617 (32.0)
 Never smoked2,735 (54.2)
Physical measurements
 Weight (kg)100.0 ± 22.3
 BMI (kg/m2)34.3 ± 6.8
 Blood pressure
  Systolic (mmHg)128.3 ± 14.7
  Diastolic (mmHg)77.3 ± 9.9
  Blood pressure <140/90 mmHg3,802 (75.3)
  Blood pressure <130/80 mmHg2,172 (43.0)
Laboratory tests*
 HbA1c (%)7.5 ± 0.5≥6.5% or 48 mmol/mol may indicate diabetes
 HbA1c (mmol/L)58 ± 5.3
 HbA1c <7%725 (14.4)
 Cholesterol (mg/dL)163.8 ± 37.8<200 mg/dL
 Cholesterol (mmol/L)4.2 ± 0.985.172 mmol/L
 Triglycerides (mg/dL)154.0 ± 121.60–100 mg/dL
 Triglycerides (mmol/L)1.7 ± 1.40–1.7 mmol/L
 HDL (mg/dL)43.4 ± 10.6Female >50 mg/dL; male >40 mg/dL
 HDL (mmol/L)1.1 ± 0.3Female >1.3 mmol/L; male >1.0 mmol/L
 LDL (mg/dL)90.5 ± 31.7<129 mg/dL
 LDL (mmol/L)2.3 ± 0.8<3.4 mmol/L
 LDL <100 mg/dL3,348 (66.3)
 UACR (mg/g)6.4 (3.1, 16.9)<30 mg albumin/g creatinine
 UACR <30 mg/g creatinine4,241 (84.1)
 Fasting glucose (mg/dL)151.5 ± 30.960–99 mg/dL
 Fasting glucose (mmol/L)8.4 ± 1.73.3–5.5 mmol/L
 eGFR (mL/min/1.73 m2)95.3 ± 16.9≥60 mL/min/1.73 m2
 eGFR <60 mL/min/1.73 m2121 (2.4)
 Serum creatinine (mg/dL)0.83 ± 0.2Female 0.4–1.1 mg/dL; male 0.5–1.2 mg/dL
 Fasting C-peptide (nmol/L)1.34 ± 0.60.37–1.47 nmol/L
 Fasting insulin (pmol/L)129.4 ± 95.412–150 pmol/L
 Fasting insulin (mU/L)21.6 ± 15.92–25 mU/L
  • Continuous data are presented as the mean ± SD or as the median (interquartile range), and categorical data are presented as n (%). UACR, urinary albumin-to-creatinine ratio.

  • *N was 5,047 except for depression/anxiety medication question (see next note).

  • †This question was added after the study started and was answered by 2,498 participants at baseline. Of these, 472 participants answered “yes” and 2,032 participants answered “no”: 472/2,502 = 0.19.