Frailty Survival Model Analysis of the National Deceased Donor Kidney Transplant Dataset Using Poisson Variance Structures
- 1 September 2005
- journal article
- Published by Informa UK Limited in Journal of the American Statistical Association
- Vol. 100 (471), 728-735
- https://doi.org/10.1198/016214505000000123
Abstract
In a recent study of transplant outcomes, donor age, cerebrovascular accident as the cause of death (CVA), renal insufficiency (serum creatinine >1.5 mg/dL), and history of hypertension have been identified as donor factors associated with elevated risk of kidney transplant failure. It is of great interest to know whether there remain other unmeasured donor factors associated with elevated risk of graft failure. In this article we study a sample of 6,024 deceased donor kidney transplants performed in 194 centers from 1995 to 2000. In addition to variation among transplant recipients, there are two other random effects: unmeasured donor and unrecorded center factors (data not available at the physician level). These two random effects are crossed, because the two kidneys from the same donor can be transplanted in different centers. Multivariate frailty models are applied to analyze the data. The likelihood functions of both parametric (e.g., with piecewise constant baseline hazard) and semiparametric multivariate frailty models are shown to be proportional to the likelihood functions of a class of mixed Poisson regression models. The penalized quasi-likelihood method is used as the numerical procedure for these mixed Poisson regression models. Thus we are able to estimate and model crossed random-effects structures for survival analysis. Although about 30% of recipient graft survival rate variation due to donor factors is explained by the measured donor characteristics, the remaining variation among donors in graft survival rate is still statistically significant, suggesting that there may be other unmeasured donor factors associated with a reduced graft survival rate. We also find significant variation of graft failure rates among transplant centers due to unrecorded center factors. Therefore, this study suggests that practice patterns at transplant centers and identification of other donor factors may merit further investigation.Keywords
This publication has 15 references indexed in Scilit:
- A hybrid estimator in nonlinear and generalised linear mixed effects modelsBiometrika, 2003
- Preface: SRTR Report on the State of TransplantationAmerican Journal of Transplantation, 2003
- Random effects Cox models: A Poisson modelling approachBiometrika, 2003
- Comparison of Mortality in All Patients on Dialysis, Patients on Dialysis Awaiting Transplantation, and Recipients of a First Cadaveric TransplantNew England Journal of Medicine, 1999
- Effect of Frailty on Marginal Regression Estimates in Survival AnalysisJournal of the Royal Statistical Society Series B: Statistical Methodology, 1999
- Analysis of interval‐grouped recurrent‐event data using piecewise constant rate functionsThe Canadian Journal of Statistics / La Revue Canadienne de Statistique, 1998
- Triple-goal Estimates in Two-stage Hierarchical ModelsJournal of the Royal Statistical Society Series B: Statistical Methodology, 1998
- Asymptotic theory for the correlated gamma-frailty modelThe Annals of Statistics, 1998
- A Nested Frailty Model for Survival Data, With an Application to the Study of Child Survival in Northeast BrazilJournal of the American Statistical Association, 1997
- Approximate Inference in Generalized Linear Mixed ModelsJournal of the American Statistical Association, 1993