Causes of death after liver transplantation.

As in many areas in medicine, database mining is in vogue in transplant hepatology. Large datasets, such as that of the United Network for Organ Sharing (UNOS), have indeed generated many high impact outcome studies that have advanced the specialty on several fronts, particularly concerning our understanding of recipient mortality. Mortality of the recipient is indeed the single most important clinical outcome when assessing the safety, efficacy, and cost-effectiveness of liver transplant surgery. UNOS and similar databases provide a wealth of knowledge on overall recipient mortality, and enable multivariable analyses of clinico-demographic variables in both donors and recipients to identify riskor protective factors for recipient mortality. Unfortunately, long-term (> 3 years) recipient survival has not had the impressive incremental improvements which we have witnessed in short-term recipient survival. Furthermore, outcome studies in liver transplantation have failed to translate into any meaningful improvement in long-term recipient survival. The questions then become: Have longterm recipient survival rates after liver transplantation reached their plateau, or is there room to improve further? And can the study of specific causes of death, rather than all-cause mortality, provide clinical insight and improve patient outcomes? To answer these important questions, the liver transplant community must make a concerted effort to collect and analyze data on causes of death after liver transplantation. Such an analysis might allow us to determine to what degree recipient deaths are related to chronic immunosuppression, and this in turn might allow us to develop individualized post-transplant care pathways to improve long-term mortality and morbidity. Liver transplant programs face challenges in collecting recipient mortality statistics, and databases fall short in providing this level of detail. Liver transplant programs usually serve large regional catchment areas, and this geography inherently hinders follow-up care and data accrual. Moreover, issues such as patient privacy, and lack of centralized computer-based health records, impose further barriers to mortality data acquisition. Our center, located in a medium-sized Canadian city, is fortunate to maintain exceptional long-term follow-up data. We postulate that the reason for this is the relative shortage of subspecialized care available in our largely rural catchment area, as well as patient and referring provider preference that recipients continue to receive indefinite long-term care at our institution. As such, our program is able to capture data on cause of death where databases, and indeed many centers, cannot. Herein, we present mortality data for 134 consecutive deaths which we tracked from 2005 to 2010. From 2000 to 2010, our center had 1-, 3-, 5and 10-year mortality rates of 8.8, 13.5, 14.8, and 16.4%, respectively. For this study, causes of death were ascertained from patient charts, autopsies (where performed), and from next-of-kin. Stata 11.0 was used for descriptive statistics. Categorical variables were reported as frequencies with percentages, and continuous variables were reported as means with standard deviation (SD). The mean ages of the study cohort at the time of transplant and at the time of death were 51.1 years (SD 10.6) and 54.6 years (SD 11.3), respectively, and 102 subjects (76.1%) were male. The mean time from transplantation to death was 3.5 years (SD 4.2). The most common underlying etiologies of liver disease were alcohol in 42 subjects (31.3%), hepatiCorrespondence and reprint request: Natasha Chandok, MD, MPH, FRCPC Assistant Professor of Medicine. Division of Gastroenterology. University of Western Ontario, Canada. Fax: 1-519-663-3858. E-mail: [email protected]