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The online version of this article (doi:10.1186/1472-6963-12-353) contains supplementary material, which is available to authorized users.
The authors declare that they have no competing interests.
RS designed and implemented the study, collected, analyzed and interpreted data, and wrote and completed the manuscript. SB contributed to the design and implementation of the study, collection of the data, and to the writing and completion of the manuscript. DRU contributed to the interpretation of data, and to the writing and completion of the manuscript. LP contributed to the interpretation of data, and to the writing and completion of the manuscript. LR contributed to the interpretation of data, and to the writing and completion of the manuscript. NNB supervised and contributed to the design and implementation the study, collection and interpretation of the data, and to the writing and completion of the manuscript. All authors read and approved the final manuscript.
Over the past years, the incidence of colorectal cancer has been increasing among young adults. A large percentage of these patients live at least 5 years after diagnosis, but it is unknown whether their rate of hospitalizations after this 5-year mark is comparable to the general population.
This is a population-based cohort consisting of 917 young adult survivors diagnosed with colorectal cancer in Ontario from 1992–1999 and 4585 matched cancer-free controls. A multistate model is presented to reflect and compare trends in the hospitalization process among survivors and their matched controls.
Analyses under a multistate model indicate that the risk of a subsequent hospital admission increases as the number of prior hospitalizations increases. Among patients who are yet to experience a hospitalization, the rate of admission is 3.47 times higher for YAS than controls (95% CI (2.79, 4.31)). However, among patients that have experienced one and two hospitalizations, the relative rate of a subsequent admission decreases to 3.03 (95% CI (2.01, 4.56)) and 1.90 (95% CI (1.19, 3.03)), respectively.
Young adult survivors of colorectal cancer have an increased risk of experiencing hospitalizations compared to cancer-free controls. However this relative risk decreases as the number of prior hospitalizations increases. The multistate approach is able to use information on the timing of hospitalizations and answer questions that standard Poisson and Negative Binomial models are unable to address.