{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,23]],"date-time":"2026-08-23T16:31:22Z","timestamp":1787502682858,"version":"build-2736575974"},"reference-count":61,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,4,27]],"date-time":"2023-04-27T00:00:00Z","timestamp":1682553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Aging Neurosci."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Association between heavy metals and Parkinson\u2019s disease (PD) is well noted, but studies regarding heavy metal levels and non-motor symptoms of PD, such as PD\u2019s dementia (PD-D), are lacking.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      In this retrospective cohort study, we compared five serum heavy metal levels (Zn, Cu, Pb, Hg, and Mn) of newly diagnosed PD patients (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u2009124). Among 124 patients, 40 patients were later converted to Parkinson\u2019s disease dementia (PD-D), and 84 patients remained without dementia during the follow-up time. We collected clinical parameters of PD and conducted correlation analysis with heavy metal levels. PD-D conversion time was defined as the initiation time of cholinesterase inhibitors. Cox proportional hazard models were used to identify factors associated with dementia conversion in PD subjects.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Zn deficiency was significant in the PD-D group than in the PD without dementia group (87.53\u2009\u00b1\u200913.20 vs. 74.91\u2009\u00b1\u200914.43,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&amp;lt;\u20090.01). Lower serum Zn level was significantly correlated with K-MMSE and LEDD at 3 months (\n                      <jats:italic>r<\/jats:italic>\n                      \u2009=\u2009\u22120.28,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&amp;lt;\u20090.01;\n                      <jats:italic>r<\/jats:italic>\n                      \u2009=\u20090.38,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&amp;lt;\u20090.01). Zn deficiency also contributed to a shorter time to dementia conversion (HR 0.953, 95% CI 0.919 to 0.988,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&amp;lt;\u20090.01).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This clinical study suggests that a low serum Zn level can be a risk factor for developing PD-D and could be used as a biological marker for PD-D conversion.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fnagi.2023.1132907","type":"journal-article","created":{"date-parts":[[2023,4,27]],"date-time":"2023-04-27T00:28:37Z","timestamp":1682555317000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":15,"title":["Serum zinc deficiency could be associated with dementia conversion in Parkinson\u2019s disease"],"prefix":"10.3389","volume":"15","author":[{"given":"Jieun","family":"Lee","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suyeon","family":"Park","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wooyoung","family":"Jang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2023,4,27]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"18","DOI":"10.1016\/j.jns.2009.08.034","article-title":"The epidemiology of dementia associated with Parkinson disease","volume":"289","author":"Aarsland","year":"2010","journal-title":"J. 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