Table 1

Baseline characteristics

CharacteristicsTotalMetformin usersNo metformin use
n1,3532891,064
Age (years)67.8 ± 11.767.3 ± 10.668.0 ± 12.0
Female sex (%)57.661.256.5
Diabetes duration (years)6.0 (3–11)4.9 (3–11)7.1 (4–12)
Smoking (%)18.619.218.4
BMI (kg/m2)28.9 ± 4.829.6 ± 5.128.8 ± 4.6*
Systolic blood pressure (mmHg)153.0 ± 25.2154.3 ± 24.9153.6 ± 25.3
A1C (%)7.5 ± 1.27.7 ± 1.17.4 ± 1.3*
eGFR (ml/min per 1.73 m2)73.9 ± 28.176.9 ± 30.073.0 ± 27.6†
Total cholesterol–to–HDL ratio5.2 ± 1.65.3 ± 1.65.1 ± 1.5
Albumin-to-creatinine ratio2.2 (1.0–7.2)2.6 (1.1–9.4)2.1 (1.0–6.8)
Macrovascular complications (%)32.735.332.1
Insulin use (%)16.55.919.3‡
Sulfonylurea use (%)55.015.965.8‡
Diet only (%)13.0
  • Data are means ± SD, median (interquartile range) for nonnormally distributed data, or %.

  • *P < 0.01;

  • P < 0.05;

  • P < 0.001, two-sided parametric test (Student t) and nonparametric test (Mann-Whitney U) as appropriate. eGFR, estimated glomerular filtration rate.