Is clozapine safe in the elderly?

Abstract

Objective: The aim of this paper is to assess the risk/benefit ratio of clozapine in the elderly.

Method: MedLine and Internet searches, followed by cross-checking for further articles, identified the references. Reports on efficacy as well as side effects were examined. Five psychogeriatric patients treated by the authors are presented.

Results: The review of the literature highlighted the lack of studies on the use of clozapine in the elderly. Retrospective studies and case reports dominate. There is only one double-blind placebo-controlled study of six patients extant. Although efficacy seemed to parallel that in the younger age groups, the incidence of leukopenia, agranulocytosis, postural hypotension and confusion was greater in the elderly. Two of the five patients reported by the authors developed agranulocytosis, bringing the Australian experience of agranulocytosis in patients over 65 years of age to 4/55.

Conclusion: The risk/benefit ratio in the elderly is distinctly higher than found in the younger population. With specific reference to agranulocytosis alone, the frequently quoted risk of 1% for patients is likely to be 5-10 times higher in the over 65 population. Caution is advised when prescribing clozapine in the psychogeriatric population.