A novel risk score that incorporates recipient and donor variables to predict 1-year mortality in the current era of lung transplantation.
BACKGROUND
In this study we sought to construct a novel scoring system to pre-operatively stratify a patient's risk of 1-year mortality after lung transplantation (LTx) based on recipient- and donor-specific characteristics.


METHODS
The UNOS database was queried for adult (≥18 years) patients undergoing LTx between May 1, 2005 and December 31, 2012. The population was randomly divided in a 4:1 fashion into derivation and validation cohorts. A multivariable logistic regression model for 1-year mortality was constructed within the derivation cohort. Points were then assigned to independent predictors (p < 0.05) based on relative odds ratios. Risk groups were established based on score ranges.


RESULTS
During the study period, 9,185 patients underwent LTx and the 1-year mortality was 18.0% (n = 1,654). There was a similar distribution of variables between the derivation (n = 7,336) and validation (n = 1,849) cohorts. Of the 14 covariates included in the final model, 9 were ultimately allotted point values (maximum score = 70). The model exhibited good predictive strength (c = 0.65) in the derivation cohort and demonstrated a strong correlation between the observed and expected rates of 1-year mortality in the validation cohort (r = 0.87). The low-risk (score 0 to 11), intermediate-risk (score 12 to 21) and high-risk (score ≥22) groups had a 10.8%, 17.1% and 32.0% risk of mortality (p < 0.001), respectively.


CONCLUSIONS
This is the first scoring system that incorporates both recipient- and donor-related factors to predict 1-year mortality after LTx. Its use could assist providers in the identification of patients at highest risk for poor post-transplant outcomes.
Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
Joshua C
JC
Grimm
Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
Vicente
V
Valero
Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
J Trent
JT
Magruder
Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
Arman
A
Kilic
Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
Samuel P
SP
Dungan
Division of Pulmonary and Critical Care, The Johns Hopkins Hospital, Baltimore, Maryland.
Leann L
LL
Silhan
Division of Pulmonary and Critical Care, The Johns Hopkins Hospital, Baltimore, Maryland.
Pali D
PD
Shah
Division of Pulmonary and Critical Care, The Johns Hopkins Hospital, Baltimore, Maryland.
Bo S
BS
Kim
Division of Pulmonary and Critical Care, The Johns Hopkins Hospital, Baltimore, Maryland.
Christian A
CA
Merlo
Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland.
Christopher M
CM
Sciortino
Division of Cardiac Surgery, The Johns Hopkins Hospital, Baltimore, Maryland. Electronic address: jgrimm4@jhmi.edu.
Ashish S
AS
Shah
D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000401:mortality / Q000601:surgery*; D016040:Lung Transplantation / Q000401:mortality*; D008297:Male; D008396:Maryland / Q000453:epidemiology; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014019:Tissue Donors / Q000600:supply & distribution*; D066027:Transplant Recipients / Q000706:statistics & numerical data*
lung transplantation; mortality; multivariable regression; risk stratification