Evidence map›Paper›PMID 42298315›Full record

ArticlePsychiatry and clinical neurosciences2026

Association between initial 30-day cumulative clozapine dose and risk of agranulocytosis: A nationwide register-based cohort study.

Yuki Kikuchi, Xue Li, Hiroshi Komatsu, Norio Yasui-Furukori, Ken Inada, Hiroaki Tomita

Abstract read
In one paragraph

Article in Psychiatry and clinical neurosciences, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Yuki KikuchiDepartment of Psychiatry, Graduate School of Medicine, Tohoku University, Sendai, Japan.ORCID https://orcid.org/0000-0002-1184-8918
Xue LiDepartment of Psychiatry, Graduate School of Medicine, Tohoku University, Sendai, Japan.
Hiroshi KomatsuDepartment of Psychiatry, Tohoku University Hospital, Sendai, Japan.
Norio Yasui-FurukoriThe Japanese Society of Clinical Neuropsychopharmacology, Tokyo, Japan.ORCID https://orcid.org/0000-0002-4414-3770
Ken InadaThe Japanese Society of Clinical Neuropsychopharmacology, Tokyo, Japan.ORCID https://orcid.org/0000-0002-3073-4588
Hiroaki TomitaDepartment of Psychiatry, Graduate School of Medicine, Tohoku University, Sendai, Japan.ORCID https://orcid.org/0000-0003-2628-880X

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

aimsClozapine-induced agranulocytosis (CIA) is traditionally considered an idiosyncratic, dose-independent reaction. However, emerging evidence suggests that clozapine-related inflammatory events may exhibit dose-dependent characteristics, leading us to hypothesize that CIA risk may similarly relate to early cumulative exposure.

methodsUsing Japan's nationwide Clozaril Patient Monitoring Service database (2009-2024), the 30-day cumulative dose following initiation was calculated for all treated patients. Participants were stratified into quartiles (Q1-Q4). CIA was defined as two consecutive absolute neutrophil counts <500/mm

resultsAmong 18,189 patients (mean age 42.9 [SD 12.7]; 46.4% female), 138 (0.76%) developed CIA, with no cases occurring within the first 30 days. The incidence rates of CIA in Q1, Q2, Q3, and Q4 were 0.44%, 0.66%, 0.74%, and 1.20%, respectively. Compared with Q1, hazard ratios (HRs) over 180 days were 1.78 (95% confidence interval [CI] 0.96-3.30; P = 0.0659), 2.01 (95% CI 1.10-3.66; P = 0.0233), and 3.07 (95% CI 1.74-5.42; P < 0.001) for Q2, Q3, and Q4, respectively. Male sex and age >40 years were identified as independent risk factors. E-values for Q4 HR were 5.59 (point estimate) and 2.88 (95% CI), indicating high robustness against unmeasured confounders such as co-medications.

conclusionsHigher early cumulative clozapine exposure was associated with increased CIA risk. These findings suggest that early exposure may serve as a clinically relevant marker of CIA risk, although causal inference is limited and further research is needed.

Indexed as

AgranulocytosisAntipsychotic AgentsClozapineRegistriesAdultCohort StudiesDose-Response Relationship, DrugFemaleHumansIncidenceJapanMaleMiddle AgedAntipsychotic AgentsClozapineCPMSinflammationmyocarditisneutropeniapersonalized titration

Identifiers

PMID42298315
PMCPMC13537344

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.