TY - JOUR
T1 - Derivation and validation of a preoperative prediction rule for delirium after cardiac surgery
AU - Rudolph, James L.
AU - Jones, Richard N.
AU - Levkoff, Sue E.
AU - Rockett, Christopher
AU - Inouye, Sharon K.
AU - Sellke, Frank W.
AU - Khuri, Shukri F.
AU - Lipsitz, Lewis A.
AU - Ramlawi, Basel
AU - Levitsky, Sidney
AU - Marcantonio, Edward R.
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2009/1/20
Y1 - 2009/1/20
N2 - Background - Delirium is a common outcome after cardiac surgery. Delirium prediction rules identify patients at risk for delirium who may benefit from targeted prevention strategies, early identification, and treatment of underlying causes. The purpose of the present prospective study was to develop a prediction rule for delirium in a cardiac surgery cohort and to validate it in an independent cohort. Methods and Results - Prospectively, cardiac surgery patients ≥60 years of age were enrolled in a derivation sample (n=122) and then a validation sample (n=109). Beginning on the second postoperative day, patients underwent a standardized daily delirium assessment, and delirium was diagnosed according to the confusion assessment method. Delirium occurred in 63 (52%) of the derivation cohort patients. Multivariable analysis identified 4 variables independently associated with delirium: prior stroke or transient ischemic attack, Mini Mental State Examination score, abnormal serum albumin, and the Geriatric Depression Scale. Points were assigned to each variable: Mini Mental State Examination ≤23 received 2 points, and Mini Mental State Examination score of 24 to 27 received 1 point; Geriatric Depression Scale >4, prior stroke/transient ischemic attack, and abnormal albumin received 1 point each. In the derivation sample, the cumulative incidence of delirium for point levels of 0, 1, 2, and ≥3 was 19%, 47%, 63%, and 86%, respectively (C statistic, 0.74). The corresponding incidence of delirium in the validation sample was 18%, 43%, 60%, and 87%, respectively (C statistic, 0.75). Conclusions - Delirium occurs frequently after cardiac surgery. Using 4 preoperative characteristics, clinicians can determine cardiac surgery patients' risk for delirium. Patients at higher delirium risk could be candidates for close postoperative monitoring and interventions to prevent delirium.
AB - Background - Delirium is a common outcome after cardiac surgery. Delirium prediction rules identify patients at risk for delirium who may benefit from targeted prevention strategies, early identification, and treatment of underlying causes. The purpose of the present prospective study was to develop a prediction rule for delirium in a cardiac surgery cohort and to validate it in an independent cohort. Methods and Results - Prospectively, cardiac surgery patients ≥60 years of age were enrolled in a derivation sample (n=122) and then a validation sample (n=109). Beginning on the second postoperative day, patients underwent a standardized daily delirium assessment, and delirium was diagnosed according to the confusion assessment method. Delirium occurred in 63 (52%) of the derivation cohort patients. Multivariable analysis identified 4 variables independently associated with delirium: prior stroke or transient ischemic attack, Mini Mental State Examination score, abnormal serum albumin, and the Geriatric Depression Scale. Points were assigned to each variable: Mini Mental State Examination ≤23 received 2 points, and Mini Mental State Examination score of 24 to 27 received 1 point; Geriatric Depression Scale >4, prior stroke/transient ischemic attack, and abnormal albumin received 1 point each. In the derivation sample, the cumulative incidence of delirium for point levels of 0, 1, 2, and ≥3 was 19%, 47%, 63%, and 86%, respectively (C statistic, 0.74). The corresponding incidence of delirium in the validation sample was 18%, 43%, 60%, and 87%, respectively (C statistic, 0.75). Conclusions - Delirium occurs frequently after cardiac surgery. Using 4 preoperative characteristics, clinicians can determine cardiac surgery patients' risk for delirium. Patients at higher delirium risk could be candidates for close postoperative monitoring and interventions to prevent delirium.
KW - Aging
KW - Cardiac surgery
KW - Cognition
KW - Delirium
KW - Depression
KW - Prediction rule
UR - http://www.scopus.com/inward/record.url?scp=59849114980&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=59849114980&partnerID=8YFLogxK
U2 - 10.1161/CIRCULATIONAHA.108.795260
DO - 10.1161/CIRCULATIONAHA.108.795260
M3 - Article
C2 - 19118253
AN - SCOPUS:59849114980
SN - 0009-7322
VL - 119
SP - 229
EP - 236
JO - Circulation
JF - Circulation
IS - 2
ER -