การศึกษาเรื่องความชุกของภาวะเม็ดเลือดขาวผิดปกติในผู้ป่วยโรคทางจิตเวช โรงพยาบาลราชบุรี ที่ได้รับยาโคลซาปีนในช่วง 5 ปีย้อนหลังและปัจจัยที่เกี่ยวข้อง

Sahakhun Udomsawangchoke

Authors

Sahakhun Udomsawangchoke Department of mental health and addiction, Ratchaburi Hospital, Ratchaburi

Keywords:

Schizophrenia, Treatment-resistant schizophrenia, Neutropenia, Agranulocytosis, Eosinophilia

Abstract

Background: Clozapine is the only medication indicated for treatment-resistant schizophrenia, severe aggressive behavior, or high suicide risk. However, its clinical use remains restricted due to concerns over life-threatening side effects, specifically agranulocytosis.

Objective: To investigate abnormalities in white blood cell (WBC) among psychiatric patients receiving Clozapine and to identify factors associated with these abnormalities.

Methods: This study conducted a retrospective medical record review of psychiatric patients aged 18 and older treated with Clozapine who underwent complete blood count (CBC) monitoring. Records with incomplete data were excluded. Collected data included general demographics, psychiatric diagnoses, Clozapine dosage, duration of treatment, and dosages of concomitant psychiatric medications. These variables were analyzed to determine their correlation with abnormal blood cell counts.

Results: A total of 157 medical records were analyzed, of which 62.42% were male and 79.61% were diagnosed with schizophrenia. A total of 1,093 CBC results were reviewed. The mean Clozapine dosage was 216.55 mg/day, with a mean treatment duration of 3,007 days. Leukopenia (low WBC count) was detected 5 times, and neutropenia (low neutrophil count) was detected 3 times; notably, no cases of agranulocytosis were found. Statistically significant findings showed that increased age (mean 62.20 ± 2.95 years) was significantly associated with leukopenia (p < 0.001) compared to patients with normal (mean 47.69 ± 10.77 years) or high WBC counts (mean 45.12 ± 11.01 years). Additionally, a shorter duration of Clozapine treatment (mean 2,176 days) was significantly associated with neutropenia (p = 0.042) compared to the normal neutrophil group (mean 3,037 days) or the high neutrophil group (mean 2,830 days).

Conclusion: This study found that leukopenia is associated with older age in patients, while neutropenia is associated with a shorter duration of Clozapine treatment. Importantly, no instances of agranulocytosis were observed during the study period.

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