Generalized longitudinal data analysis, with application to evaluating hospital utilization based on administrative database

There are many practical situations where subjects can experience recurrence of an event, the event has non-negligible duration, and both the rate of the event occurrences and the accumulative event duration are of particular interest. Well-developed methods for recurrent events analysis do not take into account the event duration, which could lead to undesirable inferences in the situations. Motivated partly by the research project with BC Cancer Agency to evaluate the hospital utilization of young cancer survivors, we develop a method to analyze recurrent event data with adjustment for event duration. Our methodology can be viewed as an extension of the well-established approaches for recurrent events. We also propose an approach to fitting semiparametric models for a general response process, which includes counting process as a special case. Data from the cancer project are used throughout the thesis to illustrate our formulation and approaches

Three-year data from the XIENCE V® INDIA study: Safety and efficacy of XIENCE V® in 1000 real world Indian patients

Background: Cardiovascular disease in Asia has reached epidemic proportions in recent years. Use of drug eluting stents in Asians has rapidly expanded with varying penetration rates across different countries. The XIENCE V® INDIA Study included ‘real world’ patients who underwent XIENCE V® stent implantation to assess short and intermediate term outcomes in Indian patients with diverse risk factors. Objective: To evaluate 3-year clinical outcomes in a cohort of ‘real world’ Indian patients with CAD being treated with XIENCE V® Everolimus Eluting Coronary Stent System. Methods: 1000 patients were enrolled from 18 sites in India between June 2008 and March 2009. Patients were included if their index procedures were completed using only XIENCE V®. There were no clinical or angiographic exclusions. An independent Clinical Events Committee adjudicated all endpoint-related events. The primary endpoint was stent thrombosis rate annually through to 3 years as defined by the Academic Research Consortium criteria. The co-primary endpoint was the composite rate of cardiac death and myocardial infarction at 1 year. Results: At 1-year the primary endpoint of definite/probable stent thrombosis rate was 0.51%. No additional very late stent thrombosis was reported through a 3-year follow up. The composite endpoint of cardiac death and any myocardial infarction was 1.9%, 2.7% and 3.1% at 1, 2 and 3 years respectively. Conclusion: Despite the high risk population of coronary artery disease, the use of XIENCE V® in 'real world' Indian patients was associated with very low clinical event rates upto three years of follow up