HIGH-RISK OF EOSINOPHILIA IN WOMEN TREATED WITH CLOZAPINE

Background: Eosinophilia associated with clozapine treatment has been reported in some studies and limited case reports. Because little is k nown regarding incidence, course, and relevance of this finding, cloza pine therapy has been terminated prematurely in some patients with ele vated eosinophil counts. Method: Records were reviewed on 118 consecut ively hospitalized, acutely psychotic patients treated over a 1-year p eriod with clozapine for at least 3 weeks. Demographic data were obtai ned on those patients, and white blood cell counts were analyzed. We r eviewed the data for predisposing factors, associated medical findings , or clinical sequelae, and performed a two-sided Fisher's exact test to determine if sex or diagnosis was associated with a higher risk of developing eosinophilia. The literature pertaining to this blood dyscr asia and its relationship to clozapine was reviewed. Results: In our p opulation, the cumulative incidence of eosinophilia among women was 23 % (13/57), a statistically significant higher risk (p <.01) than that in men (7% [4/61]). In all cases, the eosinophilia was noted between W eeks 3 and 5 of treatment and resolved without medical or psychiatric complications. Conclusion: Eosinophilia should be added to the list of commonly observed side effects of clozapine treatment. Women appear t o be at significant risk. Eosinophilia usually occurs early in therapy , spontaneously resolves, and is not associated with any known complic ations. An otherwise healthy person with this blood dyscrasia may cont inue with treatment but should be monitored closely. Further investiga tion into this finding may provide insight into the mechanism of neutr openia and other adverse reactions to clozapine.