Reuters Health Information 2006. © 2006 Reuters Ltd.
Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world. NEW YORK (Reuters Health) Jun 14 - The relative risk of suicide among older subjects is increased during the first month of therapy with selective serotonin reuptake inhibitor (SSRI) antidepressants, although the absolute risk is low, researchers in Canada report.Dr. David N. Juurlink, of the Institute for Clinical Evaluative Sciences, Toronto, and colleagues linked population-based coroner's data with patient-level prescription data, physician billing claims, and hospitalization data for more than 1.2 million subjects at least 66 years of age from 1992 to 2000.The researchers used propensity score methods to select four closely matched comparison subjects for each suicide case. A total of 1329 cases of suicide were identified. Of these, 1138 (86%) were completely matched to 4552 comparison subjects, according to the team's report in the May issue of the American Journal of Psychiatry.Compared to other antidepressants, the use of SSRIs was associated with a nearly fivefold higher risk of completed suicide (adjusted odds ratio: 4.8) during the first month of therapy.This risk was independent of recent depression diagnosis or receipt of psychiatric care. Suicide of a violent nature was more common among patients on SSRI therapy compared to other antidepressants. No increased risk of suicide was seen during the second and subsequent months of SSRI antidepressant treatment.The researchers calculated the absolute risk of suicide associated with antidepressant use by dividing the 1329 suicides by the total number of patients receiving an antidepressant during the study period. This yielded a suicide rate of 1 in 3353 SSRI-treated patients and 1 in 16,037 patients receiving other antidepressants."Several mechanisms may underlie the association between SSRI antidepressants and suicide," Dr. Juurlink and colleagues explain."During initial therapy, the risk of suicide may increase as some aspects of depression resolve (e.g., psychomotor retardation), thereby energizing the patient to suicide," they note. "Patients may also develop akathisia-like symptoms during treatment with SSRI antidepressants, which may increase the risk of suicide."Am J Psychiatry 2006;163:813-821.