Before propensity score adjustment | After propensity score adjustment | |||
---|---|---|---|---|
BI with metformin (N = 6621) | BI without metformin (N = 5737) | BI with metformin (N = 6621) | BI without metformin (N = 5737) | |
Demographics | ||||
Male (%) | 52.8 | 53.4 | 53.1 | 53.1 |
Age (years, Mean ± SD) | 54.2 ± 9.9** | 56.8 ± 10.4 | 55.5 ± 10.9 | 55.4 ± 11.0 |
Education (%) | ||||
Primary school or illiterate | 24.9 | 26.0 | 25.2 | 25.7 |
Junior high school | 30.8 | 29.2 | 30.3 | 29.8 |
Senior high school | 25.6 | 26.2 | 25.9 | 25.9 |
Junior college | 10.8 | 11.5 | 11.2 | 11.1 |
Bachelor’s degree or higher | 7.9 | 7.1 | 7.4 | 7.5 |
Hospital level (%) | ||||
Secondary hospitals | 49.8 | 50.4 | 50.1 | 50.1 |
Tertiary hospitals | 50.2 | 49.6 | 49.9 | 49.9 |
Recruitment settings (%) | ||||
Outpatient clinic | 54.5* | 51.2 | 53.0 | 53.0 |
Inpatient ward | 45.5 | 48.8 | 47.0 | 47.0 |
Current residence (%) | ||||
Urban | 69.1** | 73.2 | 71.1 | 71.1 |
Rural | 30.9 | 26.8 | 28.9 | 28.9 |
Out of pocket (%, Mean ± SD) | 42.5 ± 28.1* | 40.8 ± 27.2 | 41.7 ± 30.3 | 41.7 ± 30.7 |
Clinical | ||||
BMI (kg/m2, Mean ± SD) | 25.4 ± 3.3** | 24.2 ± 3.2 | 24.9 ± 3.5 | 24.8 ± 3.5 |
Duration of diabetes (years, Mean ± SD) | 6.2 ± 5.0* | 6.5 ± 5.3 | 6.4 ± 5.6 | 6.4 ± 5.7 |
Duration of OAD treatment (years, Mean ± SD) | 5.5 ± 4.9* | 5.7 ± 5.0 | 5.6 ± 5.4 | 5.6 ± 5.5 |
SBP (mmHg, Mean ± SD) | 130.1 ± 15.4* | 129.3 ± 15.6 | 129.9 ± 17.0 | 129.4 ± 17.2 |
DBP (mmHg, Mean ± SD) | 79.9 ± 9.2** | 79.1 ± 9.2 | 79.4 ± 10.0 | 79.6 ± 10.2 |
HbA1c at baseline (%, Mean ± SD) | 9.4 ± 1.8** | 9.2 ± 1.8 | 9.3 ± 2.0 | 9.3 ± 2.0 |
FPG at baseline (mmol/L, Mean ± SD) (missing=616) | 11.4 ± 3.5 | 11.0 ± 3.6 | 11.2 ± 3.8 | 11.2 ± 3.9 |
Hypoglycemia at baseline | ||||
Percentage (%) | 5.7 | 5.8 | 5.7 | 5.8 |
Episodes (times/100 person-year, Mean ± SD) | 1.7 ± 9.6* | 1.6 ± 9.9 | 1.7 ± 1.4* | 1.6 ± 1.4 |
Complication at baseline (%) | ||||
Macrovascular | 13.5* | 15.6 | 14.4 | 14.4 |
Microvascular | 24.6* | 27.5 | 25.9 | 25.9 |
Pre-insulin OAD type a (%) | ||||
Metformin | 87.8** | 39.1 | 96.0* | 97.3 |
Sulfonylureas | 46.5 | 48.5 | 47.4 | 47.4 |
α-glycosidase inhibitors | 18.1** | 33.6 | 23.0 | 22.8 |
Glinides | 13.4** | 18.9 | 15.4 | 15.3 |
Thiazolidinediones | 5.7 | 6.4 | 6.0 | 6.0 |
Others b | 8.7* | 9.8 | 9.2 | 9.2 |
Pre-insulin OAD number at baseline (%) | ||||
1 | 35.2** | 51.9 | 43.0 | 43.0 |
2 | 50.9 | 40.9 | 48.1 | 48.2 |
≥3 | 13.9 | 7.1 | 8.9 | 8.8 |
BI type initiated at v1 | ||||
Glargine | 69.6** | 78.1 | 74.9 | 74.9 |
Detemir | 14.4 | 12.5 | 13.7 | 13.7 |
NPH | 16.0** | 9.4 | 11.4 | 11.4 |
BI dose at v1 (U/day/kg) | 0.17 ± 0.071 | 0.18 ± 0.069 | 0.18 ± 0.46 | 0.18 ± 0.47 |