{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T18:25:42Z","timestamp":1787077542099,"version":"build-2736575974"},"reference-count":49,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T00:00:00Z","timestamp":1787011200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Foundation Dam","award":["SDAM_FOR701628"],"award-info":[{"award-number":["SDAM_FOR701628"]}]}],"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>People with cognitive impairment frequently have multiple comorbidities, and polypharmacy is highly prevalent, affecting nearly half of individuals with mild cognitive impairment and dementia. The use of potentially inappropriate medications (PIMs), including those specifically problematic for cognitive impairment (PIMcog), increases with the total number of medications and may exacerbate cognitive symptoms or increase the risk of adverse drug events. However, the prevalence of polypharmacy and PIMcog use among patients diagnosed with MCI or dementia in Norwegian specialist outpatient clinics has not been described.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We will conduct a retrospective cohort study linking national health registries to estimate the prevalence of polypharmacy and PIMcog use in the year prior to diagnosis of mild cognitive impairment or dementia. Data from the Norwegian Registry of Persons Assessed for Cognitive Symptoms will be linked to dispensing data from the Norwegian Prescribed Drug Registry and comorbidity data from the Norwegian Patient Registry. The study population will include all patients diagnosed with mild cognitive impairment or dementia in Norwegian specialist outpatient clinics from 2014 to 2024. We will estimate the twelve-month prevalence of polypharmacy and PIMcog use preceding diagnosis, compare sociodemographic and clinical characteristics between PIMcog users and non-users, and identify factors associated with PIMcog use.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Expected impact<\/jats:title>\n                    <jats:p>By describing the one-year prevalence and patterns of polypharmacy and PIMcog use and associated factors prior to mild cognitive impairment and dementia diagnosis, the findings may inform targeted deprescribing interventions and safer prescribing strategies for individuals with cognitive impairment.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0356275","type":"journal-article","created":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T17:34:59Z","timestamp":1787074499000},"page":"e0356275","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["One year pre-diagnostic prevalence and associated factors of polypharmacy and potentially inappropriate medication use in community-dwelling adults with mild cognitive impairment or dementia in Norway (2014\u20132024): A registered report protocol"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1063-5985","authenticated-orcid":true,"given":"Hege","family":"Kersten","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-2211-4294","authenticated-orcid":true,"given":"Tonje Marie B\u00f8","family":"Vaksvik","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rita","family":"Romskaug","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Torgeir","family":"Bruun Wyller","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keson","family":"Jaioun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9023-8068","authenticated-orcid":true,"given":"Edoardo","family":"Botteri","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6511-8219","authenticated-orcid":true,"given":"Geir","family":"Selb\u00e6k","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,18]]},"reference":[{"key":"pone.0356275.ref001","unstructured":"Population Projections. https:\/\/www.ssb.no\/en\/befolkning\/befolkningsframskrivinger 2024."},{"issue":"1","key":"pone.0356275.ref002","doi-asserted-by":"crossref","first-page":"363","DOI":"10.3233\/JAD-240037","article-title":"Prevalence and Determinants of Diagnosed Dementia: A Registry Linkage Study Linking Diagnosis of Dementia in the Population-Based HUNT Study to Registry Diagnosis of Dementia in Primary Care and Hospitals in Norway","volume":"99","author":"L Gj\u00f8ra","year":"2024","journal-title":"J Alzheimers Dis"},{"issue":"10452","key":"pone.0356275.ref003","doi-asserted-by":"crossref","first-page":"572","DOI":"10.1016\/S0140-6736(24)01296-0","article-title":"Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission","volume":"404","author":"G Livingston","year":"2024","journal-title":"Lancet"},{"issue":"9","key":"pone.0356275.ref004","doi-asserted-by":"crossref","DOI":"10.1136\/bmjopen-2021-058810","article-title":"Cohort profile: the Norwegian Registry of Persons Assessed for Cognitive Symptoms (NorCog) - 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