Table 2

Incidence rates per 1000 person-years (95% CI) for the long-term primary outcomes by exposure and age group

Outcome*Age groupMetforminCombination treatmentInsulin
No. of events/
no. at risk
IR/1000 p-y
(95% CI)
No. of events/
no. at risk
IR/1000 p-y
(95% CI)
No. of events/
no. at risk
IR/1000 p-y
(95% CI)
Obesity1 week–2 years11/39501.21
(0.67 to 2.19)
0/884NA10/52640.73
(0.39 to 1.36)
3–5 years19/22243.96
(2.52 to 6.20)
10/38215.04
(8.09 to 27.96)
40/38174.34
(3.18 to 5.91)
6–8 years24/108811.26
(7.55 to 16.80)
7/11240.34
(19.23 to 84.61)
83/244816.34
(13.18 to 20.27)
9–11 years8/37318.69
(9.35 to 37.38)
0/24NA32/107020.93
(14.80 to 29.60)
Hypoglycemia1 week–2 years58/39506.44
(4.98 to 8.33)
36/88420.71
(14.94 to 28.72)
61/52644.49
(3.49 to 5.77)
3–5 years5/22241.04
(0.43 to 2.49)
2/3822.99
(0.75 to 11.94)
0/3817NA
6–8 years2/10880.93
(0.23 to 3.71)
0/112NA1/24480.19
(0.03 to 1.37)
9–11 years0/373NA0/24NA0/1070NA
Hyperglycemia1 week–2 years11/39501.21
(0.67 to 2.19)
1/8840.56
(0.08 to 3.96)
15/52641.10
(0.66 to 1.82)
3–5 years8/22241.66
(0.83 to 3.32)
1/3821.49
(0.21 to 10.59)
14/38171.51
(0.90 to 2.56)
6–8 years4/10881.86
(0.70 to 4.95)
0/112N/A11/24482.13
(1.18 to 3.85)
9–11 years2/3734.60
(1.51 to 18.39)
0/24NA9/10705.79
(3.01 to 11.12)
Diabetes†1 week–2 years5/39500.55
(0.23 to 1.32)
1/8840.56
(0.08 to 3.96)
6/52640.44
(0.20 to 0.97)
3–5 years7/22201.46
(0.69 to 3.05)
0/382NA9/38110.97
(0.51 to 1.87)
6–8 years1/10800.47
(0.07 to 3.30)
0/112NA3/24370.58
(0.19 to 1.81)
9–11 years0/370NA0/24NA1/10630.64
(0.09 to 4.57)
Hypertension1 week–2 years0/3950NA0/884NA5/52640.36
(0.15 to 0.88)
3–5 years0/2224NA0/382NA1/38170.11
(0.02 to 0.77)
6–8 years0/1088NA0/112NA1/24480.19
(0.03 to 1.37)
9–11 years0/373NA0/24NA0/1070NA
Challenges in motor–social development†1 week–2 years155/395017.41
(14.87 to 20.38)
35/88419.99
(14.35 to 27.84)
133/52649.82
(8.29 to 11.64)
3–5 years264/211460.71
(53.81 to 68.49)
45/36175.42
(56.31 to 101.01)
439/371651.56
(41.91 to 55.38)
6–8 years80/89946.67
(37.49 to 58.10)
5/8136.75
(15.30 to 88.29)
198/205748.18
(41.91 to 55.38)
9–11 years6/29017.13
(7.69 to 38.12)
1/2050.48
(7.11 to 358.33)
38/81531.62
(23.00 to 43.45)
  • *No events of PCOS were observed in any of the exposure groups; no events were observed for any outcome and exposure group in the age group ≥12 years.

  • †Children with the diagnosis were removed from population at risk in the following age groups after the first diagnosis. Therefore, the number at risk were different for the outcomes after the youngest age group.

  • IR, incidence rate; NA, not applicable; PCOS, polycystic ovary syndrome; p-y, person-years.