Feasibility of venous thromboembolism prophylaxis during inflammatory bowel disease flares in the outpatient setting: a decision analysis.

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.