|Résumé: ||BACKGROUND: Organ transplantation is one of the best modalities for treating fatal organ failure. Despite the success of this procedure, an increasing incidence of cancer in this population has drawn the attention of public health officials in recent years.
OBJECTIVES: The overall objective of this study is to conduct a detailed examination of adverse health outcomes among Canadian organ transplant recipients, with an emphasis on cancer incidence and mortality.
METHODS: This project employed a retrospective cohort follow-up study design, whereby Canadian Organ Replacement Registry records were linked to the Canadian Mortality Database and the Canadian Cancer Registry Database. The study population consisted of more than 16,000 solid organ transplant recipients registered between January 1, 1981 and December 31, 1998. This study was designed to assess the risks of developing cancer, overall and site-specific, in transplant recipients in comparison to the general Canadian population using Standardized Incidence Ratios (SIR), Standardized Mortality Ratios (SMR), and Proportionate Mortality Ratios (PMR). In addition, Cox and logistic models were used to assess the effects of various risk factors on cancer incidence and mortality in transplant sub-populations, while cumulative incidence was used to study the patient survival pattern. Lastly, Population Attributable Risk (PAR) was used to quantify the impact of organ transplantation on cancer incidence and mortality.
RESULTS: Among major causes of death, the highest PMRs are due to genitourinary diseases, followed by endocrine, nutritional and metabolic diseases, and infectious diseases. SIRs indicate that cancer incidence and mortality were relatively lower than that observed for other major causes of death, and slightly higher than that observed in the general Canadian population. Lastly, logistic regression results indicate that age, year of surgery, and smoking status were significant risk factors in mortality due to all causes, while the Cox regression model shows that age, sex and year of surgery were significant risk factors for cancer incidence. Overall, the PAR in this cohort was very minimal, indicating that the risk in mortality and cancer incidence due to organ transplantation is negligible.
CONCLUSION: Life threatening diseases such as those of the genitourinary system, as well as endocrine, nutritional and metabolic diseases and infectious diseases are leading causes of death. Future research should be directed at ways of reducing incidence and subsequent mortality due to these causes.|