ArticleBMC medical research methodology2023
Association of ABO blood groups with venous thrombosis recurrence in middle-aged patients: insights from a weighted Cox analysis dedicated to ambispective design.
Article in BMC medical research methodology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers.
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Who cites it
6 citing papers in PubMed.
- Impact of ABO blood groups on residual pulmonary vascular obstruction in patients with unprovoked pulmonary embolism.Blood vessels, thrombosis & hemostasis · 2026Article
- Population-specific ABO haplotypes reveal distinct venous thromboembolism risk in East Asians: insights from a large-scale genetic study.The Lancet regional health. Western Pacific · 2026Article
- Are Blood Groups a Predictive Factor in Determining the Severity of Coronary Artery Disease in Patients Undergoing Coronary Heart Surgery?Brazilian journal of cardiovascular surgery · 2026Article
- Pulmonary Embolism and ABO Blood Type: A Systematic Review.Diagnostics (Basel, Switzerland) · 2025Review
- ABO blood type is not a risk factor of outcome in aneurysmal subarachnoid hemorrhage patients.European journal of medical research · 2024Article
- Linking Cortical Structure and Cerebrospinal Fluid Metabolites with Venous Thromboembolism Risk: A Two-Step Mendelian Randomization and Co-Localization Analysis.Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/HemostasisArticle
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10 authors.
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Abstract
backgroundIn studies of time-to-events, it is common to collect information about events that occurred before the inclusion in a prospective cohort. When the studied risk factors are independent of time, including both pre- and post-inclusion events in the analyses, generally referred to as relying on an ambispective design, increases the statistical power but may lead to a selection bias. In the field of venous thromboembolism (VT), ABO blood groups have been the subject of extensive research due to their substantial effect on VT risk. However, few studies have investigated their effect on the risk of VT recurrence. Motivated by the study of the association of genetically determined ABO blood groups with VT recurrence, we propose a methodology to include pre-inclusion events in the analysis of ambispective studies while avoiding the selection bias due to mortality.
methodsThis work relies on two independent cohorts of VT patients, the French MARTHA study built on an ambispective design and the Dutch MEGA study built on a standard prospective design. For the analysis of the MARTHA study, a weighted Cox model was developed where weights were defined by the inverse of the survival probability at the time of data collection about the events. Thanks to the collection of information on the vital status of patients, we could estimate the survival probabilities using a delayed-entry Cox model on the death risk. Finally, results obtained in both studies were then meta-analysed.
resultsIn the combined sample totalling 2,752 patients including 993 recurrences, the A1 blood group has an increased risk (Hazard Ratio (HR) of 1.18, p = 4.2 × 10
conclusionThe proposed methodology increases the power of studies relying on an ambispective design which is frequent in epidemiologic studies about recurrent events. This approach allowed to clarify the association of ABO blood groups with the risk of VT recurrence. Besides, this methodology has an immediate field of application in the context of genome wide association studies.
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