{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T04:49:11Z","timestamp":1791607751599,"version":"4.3.4"},"reference-count":36,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T00:00:00Z","timestamp":1790553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T00:00:00Z","timestamp":1790553600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundaci\u00f3n Canaria de Investigaci\u00f3n y Salud","award":["PI 08\/115"],"award-info":[{"award-number":["PI 08\/115"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background\/Objectives: Schizophrenia pathophysiology has been linked to immune dysregulation, but the role of interleukin-33 (IL-33) during acute psychotic relapse remains insufficiently investigated. This exploratory admission\u2013discharge study aimed to evaluate serum IL-33 levels in inpatients with paranoid schizophrenia and in healthy controls. Methods: Serum IL-33 was measured at midday (12:00 h) and midnight (24:00 h) in 21 inpatients with paranoid schizophrenia and 21 age- and sex-matched healthy controls (HC). Patients were sampled at admission and discharge. HC underwent one sampling day, with blood collected at both 12:00 h and 24:00 h, during the interval between the patients\u2019 admission and discharge assessments. Psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS). Results: PANSS positive and general psychopathology scores decreased from admission to discharge (p &lt; 0.001 and p = 0.008, respectively). Serum IL-33 concentrations were descriptively higher in patients than in HC, but between-group differences were not statistically significant. Midnight serum IL-33 increased from admission to discharge (214.9 \u00b1 358.0 vs. 241.2 \u00b1 379.4 pg\/mL; p = 0.028), whereas the midday change was nonsignificant. Age was inversely correlated with IL-33 in patients; associations with antipsychotic dosage and sex were not statistically significant. Conclusions: The midnight increase in IL-33 accompanied clinical improvement, but medication, hospitalization, age, and smoking remain potential confounders. These exploratory findings warrant replication and do not establish IL-33 as a diagnostic or state biomarker.<\/jats:p>","DOI":"10.3390\/jcm15197542","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T16:50:54Z","timestamp":1790614254000},"page":"7542","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Longitudinal Changes in Serum Interleukin-33 Levels During Acute Psychotic Relapse and Clinical Improvement in Schizophrenia: An Admission-Discharge Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7663-1154","authenticated-orcid":false,"given":"Armando L.","family":"Morera-Fumero","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, Dermatology, and Psychiatry, University of La Laguna, 38200 Tenerife, Canary Islands, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5503-3948","authenticated-orcid":false,"given":"Jos\u00e9 J.","family":"Tasc\u00f3n-Cervera","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Dermatology, and Psychiatry, University of La Laguna, 38200 Tenerife, Canary Islands, Spain"},{"name":"Department of Psychiatry, Dr. Negr\u00edn University Hospital, 35010 Gran Canaria, Canary Islands, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Estefania","family":"Diaz-Mesa","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Dermatology, and Psychiatry, University of La Laguna, 38200 Tenerife, Canary Islands, Spain"},{"name":"Department of Psychiatry, Canary Islands University Hospital, 38320 Tenerife, Canary Islands, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Silvia","family":"Yelmo-Cruz","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, Canary Islands University Hospital, 38320 Tenerife, Canary Islands, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Pedro","family":"Abreu-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Unit of Physiology, Department of Basic Medical Sciences, University of La Laguna, 38200 Tenerife, Canary Islands, Spain"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]},{"given":"Mar\u00eda Lourdes","family":"Fernandez-Lopez","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Dermatology, and Psychiatry, University of La Laguna, 38200 Tenerife, Canary Islands, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,28]]},"reference":[{"key":"ref_1","unstructured":"American Psychiatric Association (2000). 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