Recalibration of the delirium prediction model for ICU patients (PRE-DELIRIC): a multinational observational study.
OBJECTIVE
Recalibration and determining discriminative power, internationally, of the existing delirium prediction model (PRE-DELIRIC) for intensive care patients.


METHODS
A prospective multicenter cohort study was performed in eight intensive care units (ICUs) in six countries. The ten predictors (age, APACHE-II, urgent and admission category, infection, coma, sedation, morphine use, urea level, metabolic acidosis) were collected within 24 h after ICU admission. The confusion assessment method for the intensive care unit (CAM-ICU) was used to identify ICU delirium. CAM-ICU screening compliance and inter-rater reliability measurements were used to secure the quality of the data.


RESULTS
A total of 2,852 adult ICU patients were screened of which 1,824 (64%) were eligible for the study. Main reasons for exclusion were length of stay <1 day (19.1%) and sustained coma (4.1%). CAM-ICU compliance was mean (SD) 82 ± 16% and inter-rater reliability 0.87 ± 0.17. The median delirium incidence was 22.5% (IQR 12.8-36.6%). Although the incidence of all ten predictors differed significantly between centers, the area under the receiver operating characteristic (AUROC) curve of the eight participating centers remained good: 0.77 (95% CI 0.74-0.79). The linear predictor and intercept of the prediction rule were adjusted and resulted in improved re-calibration of the PRE-DELIRIC model.


CONCLUSIONS
In this multinational study, we recalibrated the PRE-DELIRIC model. Despite differences in the incidence of predictors between the centers in the different countries, the performance of the PRE-DELIRIC-model remained good. Following validation of the PRE-DELIRIC model, it may facilitate implementation of strategies to prevent delirium and aid improvements in delirium management of ICU patients.
Department of Intensive Care Medicine, Radboud University Medical Center, P.O. 6101 Internal Post 710, 6500 HB, Nijmegen, The Netherlands, Mark.vandenBoogaard@radboudumc.nl.
M
M
van den Boogaard
L
L
Schoonhoven
E
E
Maseda
C
C
Plowright
C
C
Jones
A
A
Luetz
P V
PV
Sackey
P G
PG
Jorens
L M
LM
Aitken
F M P
FM
van Haren
R
R
Donders
J G
JG
van der Hoeven
P
P
Pickkers
D018806:APACHE; D000328:Adult; D000367:Age Factors; D000368:Aged; D019540:Area Under Curve; D002138:Calibration; D003221:Confusion / Q000175:diagnosis; D003661:Decision Support Techniques; D003693:Delirium / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D038622:Internationality; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010343:Patient Admission / Q000706:statistics & numerical data; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results