Rosanna Irene Comoretto1, Federico Rea2, Ersilia Lucenteforte3, Alessandro Mugelli3, Gianluca Trifirò4, Silvia Cascini5, Giuseppe Roberto6, Alessandro Chinellato7, Amelia Filippelli8, Giovanni Corrao2. 1. Department of Statistics and Quantitative Methods, Division of Biostatistics, Epidemiology and Public Health, University of Milano-Bicocca, Via Bicocca degli Arcimboldi 8, Edificio U7, Milan, 20126, Italy. r.comoretto@campus.unimib.it. 2. Department of Statistics and Quantitative Methods, Division of Biostatistics, Epidemiology and Public Health, University of Milano-Bicocca, Via Bicocca degli Arcimboldi 8, Edificio U7, Milan, 20126, Italy. 3. Department of Neurosciences, Psychology, Drug Research and Children's Health, University of Florence, Florence, Italy. 4. Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy. 5. Department of Epidemiology, Lazio Regional Health Service, Rome, Italy. 6. Epidemiology Unit, Regional Agency for Healthcare Services of Tuscany, Florence, Italy. 7. Treviso Local Health Unit, Treviso, Italy. 8. Pharmacology Unit, Department of Medicine, Surgery and Dentistry, University of Salerno, Baronissi, Salerno, Italy.
Abstract
PURPOSE: The aim of this study was to estimate the proportion of bleedings that occurred among warfarin users attributable to the concomitant use of other medications. A general approach for measuring the impact of the prescriptive inappropriateness on drug adverse outcomes at the population level is described. METHODS: A meta-analysis was conducted to obtain summary relative risks of bleeding associated with concurrent use of warfarin and other medications compared to warfarin use alone. A population-based investigation was performed, in an Italian cohort of cardiopathic patients aged 65 years or older, to estimate the prevalence of concurrent users of warfarin and other medicaments. The population attributable fraction was computed by combining data on summary relative risks and prevalence of concurrent users. RESULTS: Concomitant use of warfarin and cotrimoxazole, amiodarone, quinolones, macrolides, platelet aggregation inhibitors, SSRIs, NSAIDs, and lipid-lowering agents was associated with an increased risk of bleeding. The corresponding attributable fractions were 3% (95% CI 2 to 4%), 21% (1 to 41%), 21% (17 to 25%), 9% (8 to 10%), 14% (12 to 16%), 6% (5 to 8%), 10% (1 to 20%), and 8% (0 to 18%), respectively. CONCLUSIONS: More than half of bleeding events occurring among frail elderly using warfarin are attributable to a concomitant use of warfarin with certain drugs. Because some of these drugs appear to be essential for the treatment/prevention of cardiovascular conditions, and their concomitant use with warfarin could be acceptable in some cases, proper INR-monitoring and warfarin dose adjustments are requested.
PURPOSE: The aim of this study was to estimate the proportion of bleedings that occurred among warfarin users attributable to the concomitant use of other medications. A general approach for measuring the impact of the prescriptive inappropriateness on drug adverse outcomes at the population level is described. METHODS: A meta-analysis was conducted to obtain summary relative risks of bleeding associated with concurrent use of warfarin and other medications compared to warfarin use alone. A population-based investigation was performed, in an Italian cohort of cardiopathic patients aged 65 years or older, to estimate the prevalence of concurrent users of warfarin and other medicaments. The population attributable fraction was computed by combining data on summary relative risks and prevalence of concurrent users. RESULTS: Concomitant use of warfarin and cotrimoxazole, amiodarone, quinolones, macrolides, platelet aggregation inhibitors, SSRIs, NSAIDs, and lipid-lowering agents was associated with an increased risk of bleeding. The corresponding attributable fractions were 3% (95% CI 2 to 4%), 21% (1 to 41%), 21% (17 to 25%), 9% (8 to 10%), 14% (12 to 16%), 6% (5 to 8%), 10% (1 to 20%), and 8% (0 to 18%), respectively. CONCLUSIONS: More than half of bleeding events occurring among frail elderly using warfarin are attributable to a concomitant use of warfarin with certain drugs. Because some of these drugs appear to be essential for the treatment/prevention of cardiovascular conditions, and their concomitant use with warfarin could be acceptable in some cases, proper INR-monitoring and warfarin dose adjustments are requested.
Authors: Agnes I Vitry; Elizabeth E Roughead; Emmae N Ramsay; Adrian K Preiss; Philip Ryan; Andrew L Gilbert; Gillian E Caughey; Sepehr Shakib; Adrian Esterman; Ying Zhang; Robyn A McDermott Journal: Pharmacoepidemiol Drug Saf Date: 2011-10 Impact factor: 2.890
Authors: Ahmad Al-Azayzih; Sayer I Al-Azzam; Karem H Alzoubi; Anan S Jarab; Zelal Kharaba; Rami H Al-Rifai; Munther S Alnajjar Journal: Saudi Pharm J Date: 2020-03-20 Impact factor: 4.330