| アブストラクト | INTRODUCTION: The effects of drospirenone-containing combined oral contraceptives (COCs) on the risk of venous thromboembolism (VTE) remain controversial due to the challenge in distinguishing between first-time users and restarters, and their different underlying VTE risks, in healthcare databases. OBJECTIVES: The aim of this study was to describe the challenge of studying the risk of VTE among first-time users of drospirenone-containing COCs in a healthcare database and assess the risk among first-time users and restarters. METHODS: We used data from the Clinical Practice Research Datalink to construct two cohorts. The first-time user cohort included all women aged 16-45 years who received a first ever prescription of drospirenone- or levonorgestrel-containing COCs between May 2002 and March 2015. The restarter cohort included those who were restarting a COC after a period of non-use of >/=6 months. Cox proportional hazards models adjusted for high dimensional propensity scores were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: The final cohorts included 55,139 first-time users (3582 drospirenone and 51,557 levonorgestrel) and 162,959 restarters (23,191 drospirenone and 139,768 levonorgestrel). The adjusted HR of VTE associated with drospirenone versus levonorgestrel was 3.19 (95% CI 1.12-9.08) for first-time users and 1.96 (95% CI 1.12-3.41) for restarters. CONCLUSIONS: We found an elevated risk of VTE associated with drospirenone-containing COCs in comparison with levonorgestrel-containing COCs in both cohorts. While left truncation of healthcare databases is a concern for the identification of first-time users, the use of a more explicit cohort of restarters suggests a doubling of VTE risk with drospirenone-containing COCs. |
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| 組織名 | Center for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital,;3755 Cote Ste Catherine, Montreal, QC, H3T 1E2, Canada.;Department of Epidemiology, Biostatistics, and Occupational Health, McGill;University, Montreal, QC, Canada.;Department of Medicine, McGill University, Montreal, QC, Canada.;Division of General Internal Medicine, Jewish General Hospital, Montreal, QC,;Canada.;kristian.filion@mcgill.ca.;University, Montreal, QC, Canada. kristian.filion@mcgill.ca. |
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