TY - JOUR
T1 - Creation of a quantitative recipient risk index for mortality prediction after cardiac transplantation (IMPACT)
AU - Weiss, Eric S.
AU - Allen, Jeremiah G.
AU - Arnaoutakis, George J.
AU - George, Timothy J.
AU - Russell, Stuart D.
AU - Shah, Ashish S.
AU - Conte, John
N1 - Funding Information:
Drs. Weiss and Arnaoutakis are Irene Piccinini Investigators in Cardiac Surgery. Drs. Allen and George are Hugh R. Sharp Cardiac Surgery Research Fellows. This work was supported in part by Health Resources and Services Administration contract 234-2005-370011C. The content is the responsibility of the authors alone and does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US government.
PY - 2011/9
Y1 - 2011/9
N2 - Background: No recipient risk index exists predicting short-term mortality after orthotopic heart transplantation (OHT). We utilized United Network for Organ Sharing (UNOS) data to develop a novel quantitative recipient risk score for use in OHT. Methods: A prospectively collected open cohort of 21,378 primary OHT patients (1997 to 2008) was randomly divided into subgroups. The training cohort (n = 17,079) was used for score derivation and the test cohort (n = 4,299) was used for independent validation. Recipient specific variables associated with 1-year mortality (exploratory p value < 0.2) were incorporated stepwise into a multivariable logistic regression model. The final model contained variables which maximized explanatory power (assessed by pseudo R2, area under the curve, and likelihood-ratio test). A risk index was created by apportioning points approximating the relative impact of variables on 1-year mortality. The Kaplan-Meier method was used to assess impact of risk score on short-term survival. Results: The 50-point scoring system incorporated 12 recipient specific variables. Derivation and validation cohort scores ranged from 0 to 33 and 0 to 27, respectively (mean 6.1 ± 3.7 and 6.1 ± 3.7). Each point increased the odds of 1-year death by 14% in the derivation cohort (odds ratio 1.14 [1.13 to 1.15], p < 0.001) and 15% in the validation cohort (odds ratio 1.15 [1.12 to 1.17], p < 0001). One-year survivals in the validation cohort (by increments of 3 points) were the following: 0 to 2 (92.5%); 3 to 5 (89.9%); 7 to 9 (86.3%); and 10 or greater (74.9%); p < 0.001. Patients transplanted with risk scores of 20 or higher had 1-year mortality rates greater than 50%. Conclusions: We present a novel internally validated OHT recipient risk score, which is highly predictive of 1-year mortality. This risk index may prove valuable for patient prognosis, organ allocation, and research stratification in OHT.
AB - Background: No recipient risk index exists predicting short-term mortality after orthotopic heart transplantation (OHT). We utilized United Network for Organ Sharing (UNOS) data to develop a novel quantitative recipient risk score for use in OHT. Methods: A prospectively collected open cohort of 21,378 primary OHT patients (1997 to 2008) was randomly divided into subgroups. The training cohort (n = 17,079) was used for score derivation and the test cohort (n = 4,299) was used for independent validation. Recipient specific variables associated with 1-year mortality (exploratory p value < 0.2) were incorporated stepwise into a multivariable logistic regression model. The final model contained variables which maximized explanatory power (assessed by pseudo R2, area under the curve, and likelihood-ratio test). A risk index was created by apportioning points approximating the relative impact of variables on 1-year mortality. The Kaplan-Meier method was used to assess impact of risk score on short-term survival. Results: The 50-point scoring system incorporated 12 recipient specific variables. Derivation and validation cohort scores ranged from 0 to 33 and 0 to 27, respectively (mean 6.1 ± 3.7 and 6.1 ± 3.7). Each point increased the odds of 1-year death by 14% in the derivation cohort (odds ratio 1.14 [1.13 to 1.15], p < 0.001) and 15% in the validation cohort (odds ratio 1.15 [1.12 to 1.17], p < 0001). One-year survivals in the validation cohort (by increments of 3 points) were the following: 0 to 2 (92.5%); 3 to 5 (89.9%); 7 to 9 (86.3%); and 10 or greater (74.9%); p < 0.001. Patients transplanted with risk scores of 20 or higher had 1-year mortality rates greater than 50%. Conclusions: We present a novel internally validated OHT recipient risk score, which is highly predictive of 1-year mortality. This risk index may prove valuable for patient prognosis, organ allocation, and research stratification in OHT.
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U2 - 10.1016/j.athoracsur.2011.04.030
DO - 10.1016/j.athoracsur.2011.04.030
M3 - Article
C2 - 21871277
AN - SCOPUS:80052806345
SN - 0003-4975
VL - 92
SP - 914
EP - 922
JO - Annals of Thoracic Surgery
JF - Annals of Thoracic Surgery
IS - 3
ER -