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Prospective validation of the International Warfarin Pharmacogenetics Consortium algorithm in high-risk elderly people (VIALE study)

The Pharmacogenomics Journal volume 20, pages 451–461 (2020)Cite this article

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Abstract

We assessed the predictive accuracy of the Warfarin Pharmacogenetics Consortium (IWPC) algorithm in a prospective cohort of 376 high-risk elderly patients (≥65 years) who required new treatment with warfarin for either medical (non valvular atrial fibrillation) or surgical conditions (heart valve replacement), had ≥1 comorbid conditions, and regularly used ≥2 other drugs. Follow-up visits were performed according to clinical practice and lasted for a maximum of 1 year. Two hundred and eighty-three (75%) patients achieved a stable maintenance dose. Warfarin maintenance doses were low on average (median 20.3 mg/week, interquartile range, 14.1–27.7 mg/week) and were substantially overestimated by the IWPC algorithm. Overall the percentage of patients whose predicted dose of warfarin was within 20% of the actual stable dose was equal to 37.5%, (95% CI 32.0–43.3%). IWPC algorithm explained only 31% of the actual warfarin dose variability. Modifications of the IWPC algorithm are needed in high-risk elderly people.

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Acknowledgements

The study was fully supported by the Italian Drug Agency (Agenzia Italiana per il Farmaco) study code FARM9JNT9Y. The sponsor had no role in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the article for publication. VS has been supported by Programma VALERE, University of Campania “Luigi Vanvitelli”. The authors thank Flavia Lo Passo for assistance with data management.

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Authors and Affiliations

  1. Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, Via S. Allende, 84081, Baronissi, SA, Italy

    Amelia Filippelli, Valentina Manzo, Valeria Conti & Laura Carpenito

  2. Clinical Pharmacology Unit, San Giovanni di Dio e Ruggi d’Aragona University Hospital, Via San Leonardo 1, 84131, Salerno, Italy

    Amelia Filippelli, Valentina Manzo & Valeria Conti

  3. Department of Mental Health and Preventive Medicine, University of Campania Luigi Vanvitelli, Via L. Armanni 5, 80138, Napoli, Italy

    Simona Signoriello, Vittorio Simeon & Ciro Gallo

  4. Department of Cardiac Surgery, Monaldi Hospital, Via L. Bianchi, 80131, Napoli, Italy

    Ciro Bancone

  5. Department of Medicine and Health Sciences “V.Tiberio”, University of Molise, Via F. De Sanctis 1, 86100, Campobasso, Italy

    Graziamaria Corbi & Cecilia Politi

  6. Emergency Cardiac Surgery, San Giovanni di Dio e Ruggi d’Aragona University Hospital, Via San Leonardo 1, 84131, Salerno, Italy

    Severino Iesu & Paolo Masiello

  7. Cardiac Intensive Care Unit, San Giovanni di Dio e Ruggi d’Aragona University Hospital, Via San Leonardo 1, 84131, Salerno, Italy

    Alberto Gigantino

  8. General Medicine Unit, San Giovanni di Dio e Ruggi d’Aragona University Hospital, Via San Leonardo 1, 84131, Salerno, Italy

    Maria Teresa De Donato & Marta Marracino

  9. Department of Cardiothoracic Sciences, University of Campania Luigi Vanvitelli c/o Monaldi Hospital, Via L. Bianchi, 80131, Napoli, Italy

    Alessandro Della Corte & Marisa De Feo

  10. Department of Translational Medical Sciences, Federico II University, Via S. Pansini, 5, 80131, Napoli, Italy

    Michele Cellurale & Nicola Ferrara

  11. Immunohematology and Transfusion Medicine Service, San Giovanni di Dio e Ruggi d’Aragona University Hospital, Salerno, Italy

    Massimo Frigino

  12. Internal Medicine Department, Hospital of Sarno, Via Sarno Striano, 84087, Sarno, SA, Italy

    Tiziana Ciarambino

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  1. Amelia Filippelli
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Correspondence to Ciro Gallo.

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The study was approved by the ethics committees of all participating centers. All participants gave written informed consent.

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Filippelli, A., Signoriello, S., Bancone, C. et al. Prospective validation of the International Warfarin Pharmacogenetics Consortium algorithm in high-risk elderly people (VIALE study). Pharmacogenomics J 20, 451–461 (2020). https://doi.org/10.1038/s41397-019-0129-6

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