Skip to main content
. 2022 Jan 5;10(1):e002363. doi: 10.1136/bmjdrc-2021-002363

Table 2.

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

Outcome* Age group Metformin Combination treatment Insulin
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)
Obesity 1 week–2 years 11/3950 1.21
(0.67 to 2.19)
0/884 NA 10/5264 0.73
(0.39 to 1.36)
3–5 years 19/2224 3.96
(2.52 to 6.20)
10/382 15.04
(8.09 to 27.96)
40/3817 4.34
(3.18 to 5.91)
6–8 years 24/1088 11.26
(7.55 to 16.80)
7/112 40.34
(19.23 to 84.61)
83/2448 16.34
(13.18 to 20.27)
9–11 years 8/373 18.69
(9.35 to 37.38)
0/24 NA 32/1070 20.93
(14.80 to 29.60)
Hypoglycemia 1 week–2 years 58/3950 6.44
(4.98 to 8.33)
36/884 20.71
(14.94 to 28.72)
61/5264 4.49
(3.49 to 5.77)
3–5 years 5/2224 1.04
(0.43 to 2.49)
2/382 2.99
(0.75 to 11.94)
0/3817 NA
6–8 years 2/1088 0.93
(0.23 to 3.71)
0/112 NA 1/2448 0.19
(0.03 to 1.37)
9–11 years 0/373 NA 0/24 NA 0/1070 NA
Hyperglycemia 1 week–2 years 11/3950 1.21
(0.67 to 2.19)
1/884 0.56
(0.08 to 3.96)
15/5264 1.10
(0.66 to 1.82)
3–5 years 8/2224 1.66
(0.83 to 3.32)
1/382 1.49
(0.21 to 10.59)
14/3817 1.51
(0.90 to 2.56)
6–8 years 4/1088 1.86
(0.70 to 4.95)
0/112 N/A 11/2448 2.13
(1.18 to 3.85)
9–11 years 2/373 4.60
(1.51 to 18.39)
0/24 NA 9/1070 5.79
(3.01 to 11.12)
Diabetes† 1 week–2 years 5/3950 0.55
(0.23 to 1.32)
1/884 0.56
(0.08 to 3.96)
6/5264 0.44
(0.20 to 0.97)
3–5 years 7/2220 1.46
(0.69 to 3.05)
0/382 NA 9/3811 0.97
(0.51 to 1.87)
6–8 years 1/1080 0.47
(0.07 to 3.30)
0/112 NA 3/2437 0.58
(0.19 to 1.81)
9–11 years 0/370 NA 0/24 NA 1/1063 0.64
(0.09 to 4.57)
Hypertension 1 week–2 years 0/3950 NA 0/884 NA 5/5264 0.36
(0.15 to 0.88)
3–5 years 0/2224 NA 0/382 NA 1/3817 0.11
(0.02 to 0.77)
6–8 years 0/1088 NA 0/112 NA 1/2448 0.19
(0.03 to 1.37)
9–11 years 0/373 NA 0/24 NA 0/1070 NA
Challenges in motor–social development† 1 week–2 years 155/3950 17.41
(14.87 to 20.38)
35/884 19.99
(14.35 to 27.84)
133/5264 9.82
(8.29 to 11.64)
3–5 years 264/2114 60.71
(53.81 to 68.49)
45/361 75.42
(56.31 to 101.01)
439/3716 51.56
(41.91 to 55.38)
6–8 years 80/899 46.67
(37.49 to 58.10)
5/81 36.75
(15.30 to 88.29)
198/2057 48.18
(41.91 to 55.38)
9–11 years 6/290 17.13
(7.69 to 38.12)
1/20 50.48
(7.11 to 358.33)
38/815 31.62
(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.