Antidepressants linked to suicide risk in elderly

NEW YORK, June 15 (Reuters) The risk of suicide among older patients appears to be increased during the first month of therapy with selective serotonin reuptake inhibitor (SSRI) antidepressants, but this increased risk is fairly low, researchers in Canada report.

Dr. David N. Juurlink, of the Institute for Clinical Evaluative Sciences, Toronto, and colleagues examined coroner's data, along with data on prescriptions, physician billing claims and hospitalization, for more than 1.2 million subjects who were at least 66 years of age between 1992 and 2000.

A total of 1138 individuals who suicide were identified and these individuals were closely matched to 4,552 subjects who served as comparison group, according to the team's report in the American Journal of Psychiatry.

Compared with other antidepressants, SSRIs were associated with a nearly fivefold increased risk of completed suicide during the first month of therapy. In the first 30 days of treatment, 62 patients on an SSRI committed suicide compared with 17 suicides among patients who were prescribed another type of antidepressant drug.

This risk was still seen after factoring in the effects of a recent depression diagnosis or previous psychiatric care. Suicide of a violent nature was also more common among patients on SSRI therapy compared with patients receiving other antidepressants.

However, no increased risk of suicide was observed during the second and subsequent months of SSRI antidepressant treatment.

''Several mechanisms may underlie the association between SSRI antidepressants and suicide,'' Juurlink and colleagues note.

''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. The patients may also develop feelings of restlessness during SSRI antidepressants, ''which may increase the risk of suicide.'' These findings differ from those reported online this week in the Public Library of Science Medicine journal. Researchers compared suicide rates in the US in the last 14 years with the use of an SSRI antidepressant during the same period. They found that as the number of fluoxetine (Prozac) prescriptions increased, the number of suicides decreased.

However, the researchers add that their findings don't preclude an increased suicide risk in small populations, and recommend that the relationship between suicide and SSRI drug treatment should be further examined.

REUTERS SRS RS0924