Background: Inflammatory bowel disease (IBD) patients are at increased risk of venous thromboembolism (VTE), which is most pronounced during a disease flare. We explored the cost-effectiveness of pharmacological VTE prophylaxis in an outpatient setting.
Methods: Markov decision analysis was conducted from a societal perspective to compare the relative costs and effectiveness of pharmacological VTE prophylaxis versus no anticoagulation during ambulatory IBD flares among a hypothetical cohort of 10,000 IBD patients. The time horizon was from time of IBD diagnosis until death. Univariate and probabilistic sensitivity analyses were performed.
Results: In base case analysis, VTE prophylaxis was, compared with no anticoagulation, associated with higher average costs (U.S. $141,036 versus $90,338) and quality-adjusted life-years (QALYs) (22.29 versus 22.25), yielding an incremental cost-effectiveness ratio of $1,267,450/QALY. Venous thromboembolism prophylaxis resulted in higher unadjusted life-years (47.76 life-years versus 46.67 life-years) and lower lifetime risk of VTE (6.2% versus 9.3%). The number needed to treat to prevent one VTE event over a lifetime was 32.3. Univariate sensitivity analysis showed that the incremental cost-effectiveness ratio was most sensitive to variations in the efficacy of VTE prophylaxis. In probabilistic sensitivity analysis, only 20% of 1000 simulated trials showed that VTE prophylaxis increased QALYs. In the remaining 80%, it was associated with both higher costs and fewer QALYs.
Conclusions: Although the administration of pharmacological VTE prophylaxis during IBD flares in the outpatient setting was associated with increased life-years and reduced VTE events, it was not cost effective. Moreover, the benefits of VTE prophylaxis were not robust to probabilistic sensitivity analysis.
Article first published online 23 July 2013
*Mount Sinai Hospital’s Centre for Inflammatory Bowel Disease, University of Toronto, Toronto, ON, Canada;
†Institute for Health Policy Management and Evaluation, University of Toronto, Toronto, ON, Canada;
‡Institute for Clinical Evaluative Sciences, Toronto, ON, Canada; and
§Division of Gastroenterology and Hepatology, Johns Hopkins University, Baltimore, Maryland.
Reprints: Geoffrey C. Nguyen, MD, PhD, Mount Sinai Hospital, 600 University Avenue, Rm 437 Toronto, ON M5G 1X5, Canada (e-mail: firstname.lastname@example.org).
Geoffrey C. Nguyen was supported by a New Investigator Award by the Canadian Institutes of Health Research and the Crohn’s and Colitis Foundation of Canada. The sponsor had no role in any aspect of the study.
The authors have no conflicts of interest to disclose.
Geoffrey C. Nguyen conceived and designed the study and conducted and interpreted all analyses. He drafted the article. Suraj Sharma contributed to the study design and interpretation of data and to critical revisions of the article.
Received May 10, 2013
Accepted May 15, 2013