Table 3.
Hazard ratios for chronic renal disorders overall and by subtype, by history of pre-eclampsia and timing of delivery, Denmark, 1978-2015
| Timing of delivery | History of PE | Person years (× 103) |
Any chronic renal disorder | Chronic kidney disease | Hypertensive kidney disease | Chronic tubulointerstitial nephritis | Glomerular and proteinuric diseases | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No | HR* (95% CI) | No | HR* (95% CI) | No | HR* (95% CI) | No | HR* (95% CI) | No | HR* (95% CI) | |||||||
| Early preterm | Yes | 54.0 | 62 | 3.93 (2.90 to 5.33) | 18 | 2.90 (1.70 to 4.96) | 9 | 4.19 (1.86 to 9.42) | 5 | 2.91 (1.04 to 8.11) | 30 | 5.34 (3.36 to 8.46) | ||||
| No | 449.1 | 130 | 1 (reference) | 53 | 1 (reference) | 17 | 1 (reference) | 14 | 1 (reference) | 46 | 1 (reference) | |||||
| Late preterm | Yes | 90.7 | 63 | 2.81 (2.13 to 3.71) | 17 | 2.24 (1.33 to 3.78) | † | 3.69 (1.91 to 7.13) | * | 0.93 (0.22 to 3.95) | 32 | 3.40 (2.28 to 5.06) | ||||
| No | 1027.7 | 247 | 1 (reference) | 85 | 1 (reference) | 35 | 1 (reference) | 23 | 1 (reference) | 104 | 1 (reference) | |||||
| Term | Yes | 760.4 | 317 | 2.27 (2.02 to 2.55) | 104 | 2.27 (1.85 to 2.78) | 64 | 3.06 (2.34 to 3.99) | 15 | 1.48 (0.88 to 2.51) | 134 | 2.14 (1.79 to 2.56) | ||||
| No | 17 612.6 | 3082 | 1 (reference) | 1008 | 1 (reference) | 432 | 1 (reference) | 234 | 1 (reference) | 1408 | 1 (reference) | |||||
| P value for homogeneity |
<0.001 |
0.69 |
0.70 |
0.38 |
<0.001 |
|||||||||||
HR=hazard ratio; PE=pre-eclampsia.
Early preterm delivery: delivery <34 weeks. Late preterm delivery: delivery 34-36 weeks. Term delivery: delivery ≥37 weeks.
*
All hazard ratios are adjusted for maternal age (underlying time in Cox model), maternal birth year, parity, history of gestational hypertension, and history of shortest gestation.
†
Under current Danish and European data protection laws, exact numbers cannot be given because one cell contains <5 women.