Table 3.
Subgroup analysis of clinical features and pregnancy outcomes between Pr-AKI women living at low and high altitudes
| Variables | Without HDP (N = 50) | With HDP (N = 48) | ||||
|---|---|---|---|---|---|---|
| LA N = 28 |
HA N = 22 |
P value | LA N = 21 |
HA N = 27 |
P value | |
| Residential altitude (m) | 2207.5 ± 345.4 | 3415.2 ± 244.4 | - | 2344.8 ± 199.7 | 3336.3 ± 146.9 | - |
| Age (years) | 27.6 ± 6.7 | 26.0 ± 4.6 | 0.333 | 27.9 ± 5.4 | 28.5 ± 5.0 | 0.686 |
| BMI (kg/m2) | 24.6 ± 2.4 | 24.2 ± 2.6 | 0.683 | 27.3 ± 5.2 | 27.3 ± 3.8 | 0.983 |
| SBP (mmHg) | 111.0 ± 14.9 | 110.6 ± 11.4 | 0.915 | 155.5 ± 18.2 | 153.8 ± 19.3 | 0.751 |
| DBP (mmHg) | 68.7 ± 10.2 | 69.6 ± 10.3 | 0.736 | 103.3 ± 13.6 | 101.5 ± 17.7 | 0.687 |
| Hemoglobin (g/L) | 105.4 ± 24.1 | 108.7 ± 38.6 | 0.718 | 125.5 ± 22.8 | 115.0 ± 29.9 | 0.187 |
| Serum ALB (g/L) | 27.4 ± 5.7 | 27.8 ± 4.7 | 0.826 | 25.7 ± 5.4 | 23.6 ± 6.0 | 0.212 |
| SCr (umol/L) | 91(76–109) | 90(80–113) | 0.872a | 88(76–97) | 86(77–100) | 0.592a |
| Serum UA (umol/L) | 429.1 ± 276.5 | 428.2 ± 112.5 | 0.989 | 481.4 ± 67.9 | 475.7 ± 91.5 | 0.809 |
| Maternal death (n%) | 1(3.4 %) | 1(4.5 %) | 1.000b | 1(4.7 %) | 1(3.7 %) | 0.511b |
|
Gestational age at delivery (in weeks) |
36.9 ± 3.4 | 37.0 ± 4.6 | 0.890 | 38.0 ± 1.8 | 36.3 ± 3.1 | 0.030 |
| Delivery by cesarean section (n%) | 8(30.8 %) | 7(31.8 %) | 0.938 | 10(47.6 %) | 17(63.0 %) | 0.288 |
| Pre-term birth (n%) | 7(26.9 %) | 5(25.0 %) | 0.883 | 5(23.8 %) | 12(44.4 %) | 0.138 |
| Stillbirth/neonatal death (n%) | 6(23.1 %) | 4(19.0 %) | 1.000b | 0 | 6(24.0 %) | 0.029b |
| Neonatal weight (g) | 3018.2 ± 580.1 | 3030.6 ± 461.8 | 0.942 | 2963.9 ± 537.6 | 2625.0 ± 694.4 | 0.093 |
| Apgar score at 1 min | 7.6 ± 3.8 | 7.8 ± 3.7 | 0.904 | 8.8 ± 2.1 | 7.0 ± 3.8 | 0.091 |
| IUGR (n%) | 0 | 1(5.3 %) | 0.442b | 3(20.0 %) | 8(27.6 %) | 0.480b |
| Admission to NICU (n%) | 2(7.7 %) | 1(5.0 %) | 1.000b | 5(27.8 %) | 6(24.0 %) | 1.000b |
| LBWI (n%) | 5(20.8 %) | 2(10.0 %) | 0.428b | 5(25.0 %) | 12(48.0 %) | 0.114 |
| Renal recovery on discharge (n%) | 22(91.7 %) | 13(76.5 %) | 0.212b | 9(64.3 %) | 20(83.3 %) | 0.245b |
AKI acute kidney injury; HDP hypertensive disorders of pregnancy; LA low altitude (<2500 m); HA high altitude (≥ 2500 m); BMI body mass index; SBP systolic blood pressure; DBP diastolic blood pressure; ALB albumin; SCr serum creatinine; UA uric acid; IUGR intrauterine growth restriction; LBWI low birth weight infant; NICU neonatal intensive care unit
Values for categorical variables were given as number (percentage); values for continuous variables were given as mean ± standard deviation or median (interquartile range)
P < 0.05 was considered to be statistically significant
a: Wilcoxon 2-sample tests
b: Fisher exact test