{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T07:27:39Z","timestamp":1786606059309,"version":"build-2736575974"},"reference-count":32,"publisher":"Korean Neuropsychiatric Association","issue":"8","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002647","name":"Sungkyunkwan University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002647","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002701","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2024-0040(5650)"],"award-info":[{"award-number":["2024-0040(5650)"]}],"id":[{"id":"10.13039\/501100002701","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002701","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2024-0044(0881)"],"award-info":[{"award-number":["2024-0044(0881)"]}],"id":[{"id":"10.13039\/501100002701","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002701","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2019-II19(0421)"],"award-info":[{"award-number":["2019-II19(0421)"]}],"id":[{"id":"10.13039\/501100002701","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002701","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2025-2544(3209)"],"award-info":[{"award-number":["2025-2544(3209)"]}],"id":[{"id":"10.13039\/501100002701","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002701","name":"Ministry of Education","doi-asserted-by":"publisher","award":["2024-00455553"],"award-info":[{"award-number":["2024-00455553"]}],"id":[{"id":"10.13039\/501100002701","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2021-R1-I1A2(059735)"],"award-info":[{"award-number":["2021-R1-I1A2(059735)"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100014188","name":"Ministry of Science and ICT","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100014188","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["psychiatryinvestigation.org"],"crossmark-restriction":true},"short-container-title":["Psychiatry Investig"],"published-print":{"date-parts":[[2026,8,25]]},"abstract":"<jats:p>Objective Psychotic symptoms are common in Parkinson\u2019s disease (PD), yet it remains unclear whether these manifestations reflect transient, medication-related phenomena or an increased risk of clinically diagnosed schizophrenia spectrum disorders (SSD). This study aimed to evaluate the long-term risk of incident SSD following PD using a nationwide population-based cohort and to assess whether this risk varies across demographic, lifestyle, and metabolic subgroups.Methods We conducted a retrospective cohort study using the Korean National Health Insurance Service database from 2012 to 2023. Individuals newly diagnosed with PD were identified using repeated International Classification of Diseases, 10th Revision (ICD-10) codes and matched 1:5 with controls using propensity scores. Incident SSD was defined by repeated ICD-10 diagnoses. Incidence rates, incidence rate ratios, Kaplan-Meier curves, and Cox proportional hazards models were used.Results Among 5,110 patients with PD and 25,550 matched controls, 128 and 177 incident cases of SSD were identified, respectively. The incidence rate of SSD was higher in the PD group than in controls (7.09 vs. 1.75 per 1,000 person-years), yielding an IRR of 4.06 (95% confidence interval [CI], 3.23\u20135.09). PD was associated with an increased risk of SSD after multivariable adjustment (adjusted hazard ratio 4.90; 95% CI, 3.52\u20136.81), with particularly elevated risk among individuals younger than 60 years.Conclusion PD was associated with a substantially increased long-term risk of SSD. These findings suggest that psychotic manifestations following PD may reflect persistent psychiatric morbidity rather than transient symptoms alone.<\/jats:p>","DOI":"10.30773\/pi.2026.0038","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T23:55:31Z","timestamp":1785887731000},"page":"1071-1079","update-policy":"https:\/\/doi.org\/10.30773\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Risk of Schizophrenia Spectrum Disorders Following Parkinson\u2019s Disease: A Nationwide Population-Based Cohort Study"],"prefix":"10.30773","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1226-1414","authenticated-orcid":true,"given":"Youngoh","family":"Bae","sequence":"first","affiliation":[{"name":"Department of Precision Medicine, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea"},{"name":"Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-4850-3015","authenticated-orcid":true,"given":"Seondeok","family":"Seo","sequence":"additional","affiliation":[{"name":"Department of Artificial Intelligence, Sungkyunkwan University, Suwon, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-2487-1461","authenticated-orcid":true,"given":"Daewon","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Information and Statistics, Chungnam National University, Daejeon, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8460-5933","authenticated-orcid":true,"given":"Hohyun","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Statistics, Sungshin Women\u2019s University, Seoul, Republic of Korea"},{"name":"Center for Data Science, Sungshin Women\u2019s University, Seoul, Republic of Korea"},{"name":"Human-Centered AI Institute, Sungshin Women\u2019s University, Seoul, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5632-5208","authenticated-orcid":true,"given":"Seung Won","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Precision Medicine, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea"},{"name":"Department of Artificial Intelligence, Sungkyunkwan University, Suwon, Republic of Korea"},{"name":"Personalized Cancer Immunotherapy Research Center, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea"},{"name":"Department of Family Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"12228","reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1002\/mds.26424","type":"journal-article"},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.1016\/s0140-6736(21)00218-x","type":"journal-article"},{"key":"ref3","doi-asserted-by":"publisher","DOI":"10.1136\/bmjopen-2024-095610","type":"journal-article"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1038\/nrneurol.2016.200","type":"journal-article"},{"key":"ref5","doi-asserted-by":"publisher","DOI":"10.1007\/s40265-016-0600-5","type":"journal-article"},{"key":"ref6","doi-asserted-by":"publisher","DOI":"10.1002\/mdc3.70121","type":"journal-article"},{"key":"ref7","doi-asserted-by":"publisher","DOI":"10.1001\/archneurol.2010.166","type":"journal-article"},{"key":"ref8","doi-asserted-by":"publisher","DOI":"10.1093\/ije\/dyv319","type":"journal-article"},{"key":"ref9","doi-asserted-by":"publisher","DOI":"10.1111\/1755-5922.12252","type":"journal-article"},{"key":"ref10","doi-asserted-by":"publisher","DOI":"10.1093\/ageing\/afaa250","type":"journal-article"},{"key":"ref11","first-page":"640","type":"journal-article","volume-title":"Linking 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causality of the association between smoking and Parkinson\u2019s disease","author":"Gallo","year":"2019"},{"key":"ref27","doi-asserted-by":"publisher","DOI":"10.37766\/inplasy2024.3.0093","type":"journal-article"},{"key":"ref28","doi-asserted-by":"publisher","DOI":"10.1155\/2013\/860915","type":"journal-article"},{"key":"ref29","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0066452","type":"journal-article"},{"key":"ref30","doi-asserted-by":"publisher","DOI":"10.3389\/fnagi.2018.00001","type":"journal-article"},{"key":"ref31","doi-asserted-by":"publisher","DOI":"10.4103\/0976-3147.143197","type":"journal-article"},{"key":"ref32","doi-asserted-by":"publisher","DOI":"10.1177\/08919887231195219","type":"journal-article"}],"container-title":["Psychiatry 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