{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,30]],"date-time":"2026-10-30T15:44:04Z","timestamp":1793375044360,"version":"4.5.0"},"reference-count":36,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2024,9,4]],"date-time":"2024-09-04T00:00:00Z","timestamp":1725408000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"National Institute for Health and Care Research (NIHR) Applied Research Collaboration Northwest London"},{"name":"NIHR North West London Patient Safety Research Collaboration"},{"name":"Wellcome Trust Fellowship"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Polypharmacy, prescription of multiple medications to a patient, is a major challenge for health systems. There have been no peer-reviewed studies of polypharmacy prevalence and medication cost at a population level in England.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Aims<\/jats:title>\n                    <jats:p>To determine prevalence and medication cost of polypharmacy, by patient characteristics.<\/jats:p>\n                    <jats:p>Design and setting: Retrospective cohort study of North West London electronic health records<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Method<\/jats:title>\n                    <jats:p>We quantified prevalence and direct cost of polypharmacy (five or more regular medications), stratified by demographics and frailty. We fitted a mixed-effects logistic regression for polypharmacy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Of 1.7 million adults, 167,665 (9.4%) were on polypharmacy. Age and socio-economic deprivation were associated with polypharmacy (OR 9.24 95% CI 8.99 to 9.50, age 65\u201374 compared with 18\u201344; OR 0.68 95% CI 0.65 to 0.71, least deprived compared with most). Polypharmacy prevalence increased with frailty (OR 1.53 95% CI 1.53 to 1.54 per frailty component, for White women). Men had higher odds of polypharmacy than women at average frailty (OR 1.26 95% CI 1.24 to 1.28) and with additional frailty components (OR 1.10 95% CI 1.09 to 1.10). Black people had lower odds of polypharmacy at average frailty (OR 0.82 95% CI 0.79 to 0.85, compared with White), but along with other ethnicities, saw greater odds increases with increasing frailty (OR 1.02 95% CI 1.01 to 1.03). Annual medication cost 8.2 times more for those on polypharmacy compared with not (\u00a3370.89 and \u00a345.31).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec005\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Demographic characteristics are associated with polypharmacy, after adjusting for frailty. Further research should explore why, to reduce health inequities and optimise cost associated with polypharmacy.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0308624","type":"journal-article","created":{"date-parts":[[2024,9,4]],"date-time":"2024-09-04T13:24:56Z","timestamp":1725456296000},"page":"e0308624","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":11,"title":["Polypharmacy in primary care: A population-based retrospective cohort study of electronic health records"],"prefix":"10.1371","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4735-4856","authenticated-orcid":true,"given":"Thomas","family":"Woodcock","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6338-5919","authenticated-orcid":true,"given":"Derryn","family":"Lovett","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gloria","family":"Ihenetu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vesselin","family":"Novov","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Beaney","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keivan","family":"Armani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela","family":"Quilley","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Azeem","family":"Majeed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul","family":"Aylin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,9,4]]},"reference":[{"key":"pone.0308624.ref001","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jclinepi.2018.05.002","article-title":"Polypharmacy, defined as taking five or more drugs, is inadequate in the cardiovascular setting","volume":"101","author":"N Abolhassani","year":"2018","journal-title":"Journal of Clinical Epidemiology"},{"issue":"1","key":"pone.0308624.ref002","doi-asserted-by":"crossref","first-page":"230","DOI":"10.1186\/s12877-017-0621-2","article-title":"What is polypharmacy? 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