Risperidone in the Elderly: A Pharmacoepidemiologic Study

Background: The possibly limited adverse effects of risperidone encourage interest in its use in geriatric patients.

Method: Medical records of 122 hospitalized psychogeriatric patients (ž65 years old) newly treated with risperidone were reviewed and scored for indications, doses, and effects of this novel neuroleptic.

Results: Subjects (83 women, 39 men), mean ± SD age = 76.5 ± 6.8 years (range, 65_95), were given risperidone for agitation or psychosis associated with dementia (53%), a major mood disorder (29%), or other disorders (18%). Most (77%) were also medically ill and received other psychotropic (76%) or cardiovascular agents (70%). Daily doses of risperidone averaged 1.6 ± 1.1 mg (range, 0.25_8.0) (0.025 mg/kg body wt.); 78% received 2.0 mg. Risperidone appeared to be effective in 85% of cases, but 18% were discontinued due to intolerability (11%) or inefficacy (7%). Adverse events occurred in 32% of the patients (36% of those discontinued). These adverse events included hypotension (29%) or symptomatic orthostasis (10%), cardiac arrest (1.6%) with fatality (0.8%), and extrapyramidal effects (11%) or delirium (1.6%). Benefits were associated with younger age and male gender, but not risperidone dose. Adverse effects were associated with cardiovascular disease and its treatment, cotreatment with an SRI antidepressant or valproate, and relatively rapid dose increases.

Conclusion: Risperidone appeared to be effective and may be safe for many elderly psychiatric patients with comorbid medical conditions provided that doses are low and increased slowly. Particular caution is advised in the presence of cardiovascular disease or cotreatment with other psychotropic agents.