{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:39:40Z","timestamp":1760060380512,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T00:00:00Z","timestamp":1756339200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2022R1F1A1071120"],"award-info":[{"award-number":["NRF-2022R1F1A1071120"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Background: Although several epidemiological studies have suggested a potential association between infections and Parkinson\u2019s disease (PD), relatively few have specifically examined the relationship between upper respiratory tract infections (URIs) and PD, apart from coronavirus disease 2019 (COVID-19). Objectives: We investigated whether a history of URI was associated with the diagnosis of PD among Korean individuals aged \u226540 years, using data from the Korean National Health Insurance Service\u2013Health Screening Cohort. Methods: A total of 5844 patients newly diagnosed with PD were identified and matched with 23,376 control participants at a 1:4 ratio based on age, sex, income, and geographical region. Conditional logistic regression analyses were performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for PD, adjusting for potential confounders including smoking, alcohol consumption, body mass index, blood pressure, comorbidity scores, blood glucose, and serum cholesterol levels. Results: Overall, no significant association was found between a history of URI and PD when considering a two-year exposure window. However, in the one-year window analysis, individuals with a history of URI had a modestly reduced odds of PD (\u22651, \u22652, or \u22653 episodes: (adjusted OR: 0.93, 95% CI: 0.88\u20130.97, aOR: 0.91, 95% CI: 0.87\u20130.96 and aOR: 0.92, 95% CI: 0.87\u20130.98, respectively). Subgroup analyses revealed that the inverse association was more pronounced among women, older adults (\u226565 years), and those with higher comorbidity scores. No clear dose\u2013response trend was observed across increasing frequencies of URI diagnoses. Conclusions: Our findings suggest that the apparent protective association between recent URI history and PD is unlikely to be causal and may instead reflect confounding by medication use or reverse causation related to the prodromal phase of PD. These results should therefore be interpreted with caution and regarded as hypothesis-generating. Further prospective studies incorporating detailed prescription data and long-term follow-up are warranted to clarify the role of infections and anti-inflammatory medications in the pathogenesis of PD.<\/jats:p>","DOI":"10.3390\/brainsci15090939","type":"journal-article","created":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T09:08:52Z","timestamp":1756458532000},"page":"939","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Association Between Upper Respiratory Tract Infections and Parkinson\u2019s Disease in Korean Populations: A Nested Case\u2013Control Study Using a National Health Screening Cohort"],"prefix":"10.3390","volume":"15","author":[{"given":"Hyuntaek","family":"Rim","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1655-9549","authenticated-orcid":false,"given":"Hyo Geun","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, Suseoseoul ENT Clinic, Seoul 06349, Republic of Korea"},{"name":"MD Analytics, Seoul 06349, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6513-7011","authenticated-orcid":false,"given":"Jee Hye","family":"Wee","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joo Hyun","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, Dongguk University Ilsan Hospital, Goyang 10326, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mi Jung","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Pathology, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ho Suk","family":"Kang","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology, Department of Internal Medicine, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hoang","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of California San Diego, San Diego, CA 92093, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"In Bok","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joon Ho","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6937-8093","authenticated-orcid":false,"given":"Ji Hee","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"464","DOI":"10.1016\/S1474-4422(09)70068-7","article-title":"Non-motor symptoms of Parkinson\u2019s disease: Dopaminergic pathophysiology and treatment","volume":"8","author":"Chaudhuri","year":"2009","journal-title":"Lancet Neurol."},{"key":"ref_2","first-page":"681976","article-title":"Screening for mild cognitive impairment in Parkinson\u2019s disease: Comparison of the Italian versions of three neuropsychological tests","volume":"2015","author":"Federico","year":"2015","journal-title":"Park. 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