Joint modeling of recurrent and terminal events using additive models

In this article, we propose a joint modeling approach for the analysis of recurrent event data with a terminal event. We specify an additive rates model with a multiplicative frailty for the conditional recurrent event rate, and an additive hazards frailty model for the terminal event. A shared frailty is used to account for the association between recurrent and terminal events. An estimating equation approach is developed for the marginal and association parameters in the joint model, and the asymptotic properties of the proposed estimators are established. The finite sample performance of the proposed estimators is examined through simulation studies, and an application to a medical cost study of chronic heart failure patients is illustrated.