title: Prediction of transplant-free survival in idiopathic pulmonary fibrosis patients using joint models for event times and mixed multivariate longitudinal data.
abstract: We implement a joint model for mixed multivariate longitudinal measurements, applied to the prediction of time until lung transplant or death in idiopathic pulmonary fibrosis. Specifically, we formulate a unified Bayesian joint model for the mixed longitudinal responses and time-to-event outcomes. For the longitudinal model of continuous and binary responses, we investigate multivariate generalized linear mixed models using shared random effects. Longitudinal and time-to-event data are assumed to be independent conditional on available covariates and shared parameters. A Markov chain Monte Carlo (MCMC) algorithm, implemented in OpenBUGS, is used for parameter estimation. To illustrate practical considerations in choosing a final model, we fit 37 different candidate models using all possible combinations of random effects and employ a Deviance Information Criterion (DIC) to select a best fitting model. We demonstrate the prediction of future event probabilities within a fixed time interval for patients utilizing baseline data, post-baseline longitudinal responses, and the time-to-event outcome. The performance of our joint model is also evaluated in simulation studies.
authors.affiliation: Biostatistics Collaboration Unit, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jiin
authors.initials: J
authors.lastname: Choi
authors.affiliation: Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Stewart J
authors.initials: SJ
authors.lastname: Anderson
authors.affiliation: The Dorothy P. & Richard P. Simmons Center for Interstitial Lung Disease, Division of Pulmonary, Allergy, & Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Richards
authors.affiliation: Department of Psychiatry, University of California San Diego, San Diego, California.
authors.forename: Wesley K
authors.initials: WK
authors.lastname: Thompson
keywords: Idiopathic Pulmonary Fibrosis; Joint model; Mixed continuous and binary data; Multivariate longitudinal data; Prediction model; Shared parameter model; Survival analysis