Predicting intensive care need in women with preeclampsia using machine learning – a pilot study

Figures & data

Table 1. Clinical and biochemical characteristics for the patient cohorts

	ICU-cohort n=41	PE controls n=40	p-value
Age	33 (31-35)	29 (28-31)	0.03*
BMI (kg/m^2)	27 (25-29)	27 (25-29)	1.0
ALAT (µkat/L)	0.58 (0.26-1.85)	0.2 (0.17-0.33)	0.0001**
ASAT (µkat/L)	0.81 (0.37-2.1)	0.38 (0.33-0.47)	0.0089**
Creatinine (µmol/L)	76 (62-93)	60 (52-77)	0.0042**
Uric acid (µmol/L)	453 (385-531)	377 (316-454)	0.0017**
Hemoglobin (g/L)	120 (111-132)	122 (114-128)	0.51
Platelets (x 10^9/L)	150 (122-194)	189 (135-213)	0.11
Systolic BP^1 (mmHg)	171 (164-178)	160 (155-165)	0.007**
Diastolic BP^2 (mmHg)	107 (103-112)	101 (98-103)	0.002**
Gestation days at delivery	250 (225-267)	273 (256-278)	0.002**
Antihypertensive treatment (number of drugs)	0 = n 7 1 = n 9 2 = n 15 3= n 10	0 = n 26 1 = n 13 3 = n 1	<0.001**

Values are shown as mean (95% confidence interval) for normal distributed data and median (quartiles) for not normal distributed data. A p-value <0.05 was considered significant.

*p-value <0.05, **p-value <0.01

1 Highest systolic blood pressure recorded during hospitalization or in maternity care (1-30 days prior to delivery).

2 Highest diastolic blood pressure recorded during hospitalization or in maternity care (1-30 days prior to delivery).

Creatinine is not significant in t-test (p=0.09), but in non-parametric test (Kolmogorov-Smirnov).

Table 2a. Uric acid corrected for gestational age in the patient cohorts.

Min	1st Qu.	Median	Mean	3rd Qu.	Max	Sd
-0.03571	2.87500	3.94340	4.09974	5.37500	11.52830	2.3608

Descriptive statistics of z-score for uric acid in the ICU-cohort

Table 2b. Uric acid corrected for gestational age in the patient cohorts.

Min	1st Qu.	Median	Mean	3rd Qu.	Max	Sd
-0.5536	0.9018	2.0089	2.2197	3.8125	5.2143	1.6881

Descriptive statistics of z-score for uric acid in the PE-controls

Table 3. Reasons for admission to the intensive care unit beyond PE

	Number of patients
Dysregulated hypertension	n = 5
HELLP syndrome	n = 13
Postpartum hemorrhage	n = 8
Eclampsia	n = 9
Infection	n = 1
Kidney failure	n = 3
Pulmonary oedema/heart failure	n = 2

Reasons for admission to intensive care for the forty-one patients in the intensive care cohort beyond PE-diagnosis.

Figure 1. Predictive performance of the cross-validated ensemble prediction. Left figure shows the receiver operating characteristic curve and the area under the curve. The right figure is the prediction confusion matrix.

Figure 2. Internal validation results. Left figure shows the receiver operating characteristic curve and the area under the curve. The right figure is the prediction confusion matrix.

Data availability statement

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.