Thrombosis Risk in Adolescents and Young Adults Starting Estrogen

Cincinnati Childrens Hosp Med Ctr, Cincinnati OH

Investigators

Abstract

Estrogen is prescribed for a variety of purposes in youth, and it may increase the risk of thrombosis. While he-matologists often evaluate patients before estrogen start who are at higher risk of thrombosis due to per-sonal/family risk factors, there are no guidelines or data to inform management in some situations. This lack of data leads to significant variation in clinical practice that may compromise care. Because this knowledge gap hinders the ability of clinicians caring for youth and hematologists to provide optimal care to patients, the objec-tives of this proposal are to prospectively examine biologic changes associated with thrombotic risk in a cohort of youth who are prescribed estrogen and to examine the attitudes and practices of clinicians who make deci-sions about thromboprophylaxis for youth on estrogen. The proposed work is relevant to the priorities of under-standing human biology (defining changes in thrombotic risk associated with estrogen) and reducing human disease (defining which youth may benefit from thromboprophylaxis). The proposed research is innovative in the focus on youth, comprehensive examination of changes in coagulation factors in youth taking estrogen, and determination of factors influencing the treatment recommendations of hematologists for thromboprophy-laxis among youth with personal and/or family risk factors for thrombosis. The specific aims are to: 1) prospec-tively determine changes in coagulation that would predispose to thrombosis over the first 24 months of estro-gen in a population of people who are up to age 22 years at estrogen start; and 2) characterize the attitudes, practices, and intentions of hematologists caring for youth toward recommending thromboprophylaxis to youth with personal and/or family risk factors for thrombosis. In Aim 1, 75 people up to 22 years of age who are start-ing estrogen will undergo thorough and systematic evaluation of hemostatic factors at baseline prior to estro-gen start, and then at 3, 6, 12, 18, and 24 months, with interim telephone study visits. Hormone usage and ad-herence, coagulation parameters, thrombophilia polymorphisms, and platelet activation will be assessed. In Aim 2, well-established qualitative and survey research methods will be used. Up to 20 adult and pediatric he-matologists will complete individual interviews. Data from these interviews will be used to generate items for a new survey that will undergo survey development methods (cognitive interviews, pilot testing) before being fielded to a sample of U.S. and Canadian hematologists to understand their attitudes, behaviors, and intentions to recommend thromboprophylaxis to youth taking estrogen who are at higher risk for thrombosis and factors associated with these intentions. The results of this work provide the foundation for 1) an intervention targeting physicians to improve knowledge of thrombosis risk in the setting of estrogen use and 2) development of clini-cal guidance to aid in referral, evaluation, and management of youth at higher risk for thrombosis.