{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T23:47:20Z","timestamp":1787960840667,"version":"build-2784847793"},"reference-count":24,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T00:00:00Z","timestamp":1780012800000},"content-version":"vor","delay-in-days":49,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,10]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background and Hypothesis<\/jats:title>\n                    <jats:p>Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia, but use is constrained by potentially life-threatening neutropenia and mandatory hematological monitoring. Evidence from Western cohorts suggests risk is concentrated early in treatment, yet data from Japan where monitoring is stringent, remain limited.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Study Design<\/jats:title>\n                    <jats:p>Retrospective study including all patients prescribed clozapine from July 2009-January 2020 in Japan. Mild neutropenia was defined as absolute neutrophil count (ANC) 1.0-1.5\u2009\u00d7\u2009109\/L, and serious neutropenia as ANC &amp;lt;1.0\u2009\u00d7\u2009109\/L. Cumulative incidence of first mild and serious neutropenia was estimated using competing-risks methods. Associations with serious neutropenia were examined using Fine\u2013Gray regression, including 2-week titration rate.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Study Results<\/jats:title>\n                    <jats:p>The cohort comprised 8263 individuals contributing 764\u2009180 blood tests, with a median follow-up of 102\u00a0weeks. Overall, 3.0% patients experienced mild neutropenia and 2.2% had serious neutropenia. Among clozapine-na\u00efve patients, cumulative incidence was 1.8% for mild and 1.6% for serious neutropenia at 18\u00a0weeks, rising to 3.1% and 2.5% at 104\u00a0weeks, respectively. Faster clozapine titration rate was associated with higher incidence of serious neutropenia (sub-distribution hazard ratio [sHR] 1.22, 95% CI, 1.02-1.45 per 50\u00a0mg dosage increase at 2-weeks), as was older age (sHR 1.05, 95% CI, 1.04-1.06), while prior clozapine exposure was associated with lower incidence (sHR 0.27, 95% CI, 0.09-0.86).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In Japan, neutropenia among clozapine-treated patients accrued predominantly within the first 1-2\u00a0years, with faster titration in the first 2-weeks being associated with a 22% increase in serious neutropenia risk per 50\u00a0mg. These findings support risk-stratified, less intensive monitoring approaches beyond the first 2 years.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/schbul\/sbag087","type":"journal-article","created":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T12:19:51Z","timestamp":1777637991000},"source":"Crossref","is-referenced-by-count":1,"title":["Clozapine-Associated Neutropenia among People on Clozapine in Japan: A Nationally Representative Retrospective Cohort Study"],"prefix":"10.1093","volume":"52","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5978-3407","authenticated-orcid":false,"given":"Mike","family":"Trott","sequence":"first","affiliation":[{"name":"Addiction and Mental Health Service, Metro South Health , Woolloongabba, QLD 4102 ,","place":["Australia"]},{"name":"Faculty of Health, Medicine and Behavioural Science, University of Queensland , Brisbane, QLD 4067 ,","place":["Australia"]},{"name":"Physical and Mental Health Stream, Queensland Centre for Mental Health Research , Wacol, QLD 4076 ,","place":["Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Korinne","family":"Northwood","sequence":"additional","affiliation":[{"name":"Addiction and Mental Health Service, Metro South Health , Woolloongabba, QLD 4102 ,","place":["Australia"]},{"name":"Faculty of Health, Medicine and Behavioural Science, University of Queensland , Brisbane, QLD 4067 ,","place":["Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takeo","family":"Hata","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Osaka Medical and Pharmaceutical University Hospital , Takatsuki, Osaka 569-8686 ,","place":["Japan"]},{"name":"Department of Medical Informatics, Osaka Medical and Pharmaceutical University , Takatsuki, Osaka 569-8686 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keiichiro","family":"Nishida","sequence":"additional","affiliation":[{"name":"Department of Neuropsychiatry, Osaka Medical and Pharmaceutical University , Takatsuki, Osaka 569-8686 ,","place":["Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2072-9216","authenticated-orcid":false,"given":"Dan","family":"Siskind","sequence":"additional","affiliation":[{"name":"Addiction and Mental Health Service, Metro South Health , Woolloongabba, QLD 4102 ,","place":["Australia"]},{"name":"Faculty of Health, Medicine and Behavioural Science, University of Queensland , Brisbane, QLD 4067 ,","place":["Australia"]},{"name":"Physical and Mental Health Stream, Queensland Centre for Mental Health Research , Wacol, QLD 4076 ,","place":["Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tetsufumi","family":"Kanazawa","sequence":"additional","affiliation":[{"name":"Department of Neuropsychiatry, Osaka Medical and Pharmaceutical University , Takatsuki, Osaka 569-8686 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