A risk-benefit analysis of factor V Leiden testing to improve pregnancy outcomes: a case study of the capabilities of decision modeling in genomics

Purpose: We sought to assess the benefits, risks, and personal utility of factor V Leiden mutation testing to improve pregnancy outcomes and to assess the utility of decision-analytic modeling for complex outcomes in genomics. Methods: We developed a model to evaluate factor V Leiden testing among women with a history of recurrent pregnancy loss, including heparin therapy during pregnancy in mutation-positive women. Outcomes included venous thromboembolism, major bleeds, pregnancy loss, maternal mortality, and quality-adjusted life-years. Results: Factor V Leiden testing in a hypothetical cohort of 10,000 women led to 7 fewer venous thromboembolic events, 90 fewer pregnancy losses, and an increase of 17 major bleeding events. Small improvements in quality-adjusted life-years were largely attributable to reduced mortality but also to improvements in health-related quality of life. However, sensitivity analyses indicate large variance in results due to data uncertainty. Furthermore, the complexity of outcomes limited our ability to fully capture the repercussions of testing in the quality-adjusted life-year measure. Conclusion: Factor V Leiden testing involves tradeoffs between clinical and personal utility, and additional effectiveness data are needed for heparin use to prevent pregnancy loss. Decision-analytic methods offer somewhat limited value in assessing these tradeoffs, suggesting that evaluation of complex outcomes will require novel approaches to appropriately capture patient-centered outcomes.