Trial reportThrombosis and haemostasis2015
The effect of calcium plus vitamin D supplementation on the risk of venous thromboembolism. From the Women's Health Initiative Randomized Controlled Trial.
Trial report in Thrombosis and haemostasis, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers, 1 of them a synthesis that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
14 citing papers in PubMed, 1 synthesis or guideline pooled it, 26 citations in OpenAlex.
- Is Circulating Vitamin D Status Associated with the Risk of Venous Thromboembolism? A Meta-Analysis of Observational Studies.Nutrients · 2023Pooled it
- Article
- Effects of Cocoa Extract and Multivitamin Supplementation on Venous Thromboembolism in the COSMOS Trial.Thrombosis and haemostasis · 2026Article
- Recent Updates and Advances in the Association Between Vitamin D Deficiency and Risk of Thrombotic Disease.Nutrients · 2024Review
- Dispensed prescription medications and short-term risk of pulmonary embolism in Norway and Sweden.Scientific reports · 2024Article
- Emerging role of vitamin D deficiency as a risk factor for retinal venous occlusions and need for public health measures for its prevention.Journal of family medicine and primary care · 2024Article
- Review
- Influence of Vitamin D Status on the Maintenance Dose of Warfarin in Patients Receiving Chronic Warfarin Therapy.Cardiology and therapy · 2022Article
- Rays of immunity: Role of sunshine vitamin in management of COVID-19 infection and associated comorbidities.Clinical nutrition ESPEN · 2021Review
- Exploring the link between vitamin D and clinical outcomes in COVID-19.American journal of physiology. Endocrinology and metabolism · 2021Article
- Thrombin generation and fibrin clot structure after vitamin D supplementation.Endocrine connections · 2019Article
- Emerging Role of Vitamin D and its Associated Molecules in Pathways Related to Pathogenesis of Thrombosis.Biomolecules · 2019Review
- Coagulation and fibrinolysis in hyperparathyroidism secondary to vitamin D deficiency.Endocrine connections · 2018Article
- Identification of Regulatory Mutations in SERPINC1 Affecting Vitamin D Response Elements Associated with Antithrombin Deficiency.PloS one · 2016Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
14 authors at 1 institution in 1 country.
Funding
Abstract
Experimental and epidemiological studies suggest that vitamin D may be implicated in haemostatic regulations and influence the risk of venous thromboembolism (VTE). The aim of this study was to investigate whether oral supplementation of vitamin D3 combined with calcium reduces the risk of VTE. In the randomised, double-blind, placebo-controlled Women's Health Initiative Calcium Plus Vitamin D trial, 36,282 postmenopausal women aged 50-79 years were randomised to receive 1,000 mg of calcium carbonate and 400 IU of vitamin D3 per day (n=18,176) or a matching placebo (n=18,106) during an average of seven years. This secondary analysis of the trial compared the incidence of VTE by treatment group using an intention-to-treat Cox regression analysis. The incidence of VTE did not differ between women randomised to calcium plus vitamin D and women randomised to placebo (320 vs 348 VTE events, respectively; hazard ratio (HR) 0.92, 95 % confidence interval (CI) 0.79-1.07). Results were not modified in an analysis using inverse-probability weights to take non-adherence into account (HR 0.94, 95 %CI 0.73-1.22) or in multiple subgroups. Whereas the risk of a non-idiopathic VTE was similar between groups, the risk of idiopathic VTE was lower in women randomised to calcium plus vitamin D (40 vs 65 events; HR 0.62, 95 %CI 0.42-0.92). In conclusion, daily supplementation with 1,000 mg of calcium and 400 IU of vitamin D did not reduce the overall incidence of VTE in generally healthy postmenopausal women. However, the observed reduced risk of idiopathic VTE in women randomised to calcium and vitamin D warrants further investigations.
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