Table 3.
Incidence of early-onset type 2 diabetes and hazard ratios (CI95) according to exposure variables in the sibling cohort
| Cases | Person-years | Incidence rate* | Model 1 | Model 2 | |
|---|---|---|---|---|---|
| Sex | |||||
| Women | 1 174 | 29 757 | 39.45 | 1.00 | |
| Men | 1 298 | 34 283 | 37.86 | 0.90 (0.80—1.02) | |
| BMI of the mother in early pregnancy | |||||
| < 18.5 kg/m2 | 85 | 2 224 | 38.22 | 1.08 (0.72–1.63) | 1.04 (0.69–1.57) |
| ≥ 18.5 and < 25 kg/m2 | 986 | 25 355 | 38.89 | 1.00 | 1.00 |
| ≥ 25 and < 30 kg/m2 | 413 | 10 599 | 38.97 | 0.94 (0.76–1.16) | 0.94 (0.76–1.17) |
| ≥ 30 kg/m2 | 180 | 4 553 | 39.53 | 0.87 (0.63–1.18) | 0.92 (0.67–1.27) |
| Exposure to maternal diabetes during pregnancy | |||||
| No | 2 353 | 61 465 | 38.28 | 1.00 | 1.00 |
| Yes | 119 | 2 575 | 46.21 | 1.18 (0.76–1.85) | 1.25 (0.79–1.96) |
| Smoking during pregnancy | |||||
| No smoking | 1 328 | 34 513 | 38.48 | 1.00 | 1.00 |
| Smoking | 965 | 25 198 | 38.30 | 1.08 (0.84–1.39) | 1.02 (0.79–1.32) |
| 1 to 9 cigarettes per day | 500 | 13 202 | 37.87 | 1.04 (0.80–1.36) | 0.99 (0.75–1.29) |
| 10 or more cigarettes per day | 465 | 11 996 | 38.76 | 1.15 (0.86–1.53) | 1.08 (0.80–1.45) |
| Infection during pregnancy | |||||
| No | 2 370 | 61 417 | 38.59 | 1.00 | 1.00 |
| Yes | 102 | 2 623 | 38.89 | 0.98 (0.72–1.34) | 0.94 (0.68–1.29) |
| Pre-eclampsia | |||||
| No | 2 370 | 61 800 | 38.35 | 1.00 | 1.00 |
| Yes | 102 | 2 240 | 45.53 | 1.18 (0.80–1.73) | 1.08 (0.73–1.61) |
| Gestational age | |||||
| Non-full-term birth (< 39 weeks) | 706 | 17 581 | 40.16 | 1.14 (0.97–1.33) | 0.97 (0.82–1.15) |
| Extremely to very preterm (≥ 22 to < 32 weeks) | 33 | 503 | 65.60 | 4.30 (1.68–10.96) | 2.25 (0.83–6.07) |
| Moderate to late preterm (≥ 32 to < 37 weeks) | 162 | 3 690 | 43.90 | 1.21 (0.90–1.63) | 0.87 (0.63–1.22) |
| Early birth term (≥ 37 to < 39 weeks) | 511 | 13 388 | 38.17 | 1.09 (0.92–1.29) | 0.98 (0.82–1.16) |
| Full term (≥ 39 weeks) | 1 759 | 46 298 | 37.99 | 1.00 | 1.00 |
| Birth weight | |||||
| < 2500 g | 173 | 3 127 | 55.33 | 2.60 (1.83–3.69) | 2.48 (1.65–3.72) |
| ≥ 2500 g and < 3500 g | 1 232 | 30 139 | 40.88 | 1.34 (1.15–1.56) | 1.35 (1.15–1.58) |
| ≥ 3500 g and < 4500 g | 966 | 27 643 | 34.94 | 1.00 | 1.00 |
| ≥ 4500 g | 91 | 2 945 | 30.90 | 0.73 (0.51–1.03) | 0.72 (0.51–1.03) |
| Size for gestational age** | |||||
| Small for gestational age | 171 | 3 048 | 56.10 | 2.11 (1.51–2.93) | 2.05 (1.47–2.86) |
| Normal for gestational age | 2 162 | 57 393 | 37.67 | 1.00 | 1.00 |
| Large for gestational age | 123 | 3 260 | 37.73 | 1.01 (0.74–1.40) | 1.02 (0.73–1.40) |
| Mode of delivery | |||||
| Vaginal delivery | 2 169 | 57 054 | 38.02 | 1.00 | 1.00 |
| C section | 303 | 6 986 | 43.37 | 1.19 (0.89–1.60) | 1.05 (0.77–1.44) |
*For 1 000 person years
Model 1: each association with early-onset T2D is separately adjusted for sex
Model 2: mutual adjustment for sex, maternal BMI, diabetes, smoking and infection during pregnancy, pre-eclampsia, gestational age, birth weight, and mode of delivery
**In Model 2, size for gestational age was adjusted for the same variables except gestational age and birth weight