Table 4 Subgroup analysis according to the characteristics of diabetes in quartile 4 versus fasting glucose variability of quartiles 1–3

Duration of diabetes^a

  < 5 years (n = 412310)

4.02

1.01 (0.97–1.06)

2.63

1.03 (0.98–1.08)

7.41

1.16 (1.12–1.19)

  ≥ 5 years (n = 211927)

7.74

1.17 (1.12–1.22)

4.66

1.17 (1.11–1.24)

12.87

1.22 (1.18–1.26)

  P for interaction

< 0.001

0.001

0.011

Baseline fasting glucose^a

  < 126 mg/dL (n = 188779)

6.30

1.21 (1.15–1.27)

3.94

1.16 (1.09–1.23)

11.64

1.17 (1.13–1.21)

  ≥ 126 mg/dL (n = 435458)

4.81

0.95 (0.92–0.99)

3.03

1.01 (0.96–1.06)

8.20

1.11 (1.08–1.14)

  P for interaction

< 0.001

< 0.001

< 0.001

Subtype of diabetes^a

 T2DM (n = 608626)

5.02

1.14 (1.11–1.17)

3.26

1.14 (1.10–1.19)

9.70

1.22(1.19–1.25)

 T1DM (n = 15611)

13.49

1.11 (0.99–1.24)

8.01

0.96 (0.84–1.11)

26.23

1.25(1.15–1.35)

  P for interaction

0.267

0.065

0.186

Metformin^b

 No (n = 327239)

4.05

1.17 (1.12–1.22)

2.48

1.18 (1.12–1.25)

8.59

1.30 (1.26–1.34)

 Yes (n = 296998)

7.22

1.18 (1.13–1.22)

4.72

1.16 (1.11–1.22)

12.80

1.25 (1.22–1.29)

 P for interaction

0.622

0.976

0.150

Sulfonylurea^b

 No (n = 323998)

3.56

1.19 (1.13–1.24)

2.48

1.18 (1.12–1.25)

7.42

1.30 (1.26–1.34)

 Yes (n = 300239)

7.72

1.17 (1.13–1.21)

4.72

1.16 (1.11–1.22)

14.16

1.26 (1.23–1.30)

  P for interaction

0.858

0.976

0.380

Meglitinide^b

 No (n = 608306)

5.19

1.17 (1.13–1.20)

3.34

1.16 (1.12–1.20)

10.02

1.27 (1.25–1.30)

 Yes (n = 15931)

10.02

1.28 (1.11–1.48)

6.51

1.37(1.15–1.64)

20.14

1.37 (1.24–1.52)

  P for interaction

0.139

0.056

0.080

Thiazolidinedione^b

 No (n = 573541)

5.21

1.17 (1.14–1.21)

3.37

1.17 (1.13–1.22)

10.17

1.28 (1.25–1.31)

 Yes (n = 50696)

6.44

1.17 (1.06–1.29)

3.97

1.13 (0.99–1.28)

11.37

1.25 (1.16–1.34)

 P for interaction

0.969

0.561

0.526

DPP-4 inhibitor^b

 No (n = 576404)

5.25

1.17 (1.13–1.20)

3.37

1.17 (1.13–1.21)

10.23

1.27 (1.25–1.30)

 Yes (n = 47833)

6.06

1.21 (1.09–1.35)

4.06

1.18 (1.03–1.35)

10.63

1.35 (1.24–1.46)

  P for interaction

0.287

0.835

0.079

a-Glucosidase inhibitor^b

 No (n = 543357)

4.70

1.15 (1.12–1.19)

3.09

1.15 (1.10–1.20)

9.29

1.28 (1.25–1.31)

 Yes (n = 80880)

9.92

1.23 (1.16–1.32)

5.94

1.24 (1.14–1.34)

17.62

1.25 (1.19–1.31)

  P for interaction

0.053

0.157

0.519

Insulin^b

 No (n = 580262)

4.75

1.15 (1.11–1.18)

3.05

1.14 (1.10–1.19)

9.02

1.24 (1.22–1.27)

 Yes (n = 43975)

11.68

1.11 (1.03–1.19)

7.68

1.08 (0.99–1.18)

24.31

1.19 (1.13–1.25)

  P for interaction

0.874

0.568

0.492