Clozapine and anemia

A 2-year follow-up study

Jimmy Lee, Robert Bies, Amaal Bhaloo, Valerie Powell, Gary Remington

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Objective: Clozapine's association with agranulocytosis led to the implementation of stringent and mandatory hematologic monitoring guidelines in most countries. Although other hematologic aberrations such as eosinophilia and neutropenia have been previously described, clozapine's impact on the erythroid lineage has not been studied. There is a suspicion that a higher rate of anemia is observed in patients receiving clozapine; therefore, we hypothesized that there would be a higher rate of anemia in patients receiving clozapine therapy. Method: All individuals initiated on clozapine at our center from 2009 to 2010 were recruited. Information on age, gender, medical comorbidities, and smoking status was extracted from the medical records. Data from complete blood counts over a 2-year follow-up period were extracted, with anemia defined as a hemoglobin value below 120 g/L for women and 130 g/L for men. Time to anemia event was calculated and Cox regression was employed to identify predictors of anemia. Results: We found a high incidence of anemia in the first 2 years following clozapine initiation; of the 94 individuals (68 men, 26 women) recruited, 23 (24.5%) developed anemia. Higher baseline hemoglobin level (hazard ratio [HR] = 0.86, P = .002) and smoking status (HR = 0.21, P = .021) were identified as significant protective factors against anemia in men but not in women (HR = 0.92, P = .184, and HR = 0.52, P = .467 for baseline hemoglobin and smoking, respectively). Conclusions: Although smoking appears to lower the risk of anemia, we believe this is due to smoking's upregulation of hemoglobin levels. Further studies are warranted in light of the present findings; for example, we cannot exclude the possibility that anemia was an epiphenomenon, characterizing instead a population with severe mental illness.

Original languageEnglish (US)
Pages (from-to)1642-1647
Number of pages6
JournalJournal of Clinical Psychiatry
Volume76
Issue number12
DOIs
StatePublished - Dec 1 2015

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Clozapine
varespladib methyl
Anemia
Smoking
Hemoglobins
Agranulocytosis
Blood Cell Count
Eosinophilia
Neutropenia
Medical Records
Comorbidity
Up-Regulation
Guidelines

ASJC Scopus subject areas

  • Psychiatry and Mental health

Cite this

Clozapine and anemia : A 2-year follow-up study. / Lee, Jimmy; Bies, Robert; Bhaloo, Amaal; Powell, Valerie; Remington, Gary.

In: Journal of Clinical Psychiatry, Vol. 76, No. 12, 01.12.2015, p. 1642-1647.

Research output: Contribution to journalArticle

Lee, J, Bies, R, Bhaloo, A, Powell, V & Remington, G 2015, 'Clozapine and anemia: A 2-year follow-up study', Journal of Clinical Psychiatry, vol. 76, no. 12, pp. 1642-1647. https://doi.org/10.4088/JCP.14m09143
Lee, Jimmy ; Bies, Robert ; Bhaloo, Amaal ; Powell, Valerie ; Remington, Gary. / Clozapine and anemia : A 2-year follow-up study. In: Journal of Clinical Psychiatry. 2015 ; Vol. 76, No. 12. pp. 1642-1647.
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