SSRI antidepressants associated with increased risk of suicide in the first month of therapy

A new study  from the Institute for Clinical Evaluative Sciences (ICES) shows that elderly patients who take the antidepressants known as selective serotonin reuptake inhibitors (SSRIs) are nearly five times more likely to commit suicide during the first month of therapy compared to those prescribed other antidepressants.

“Earlier case reports describe intense suicidal thoughts during the first weeks of SSRI therapy. However, this is a challenging problem to study on a larger scale because it is difficult to separate the role of depression from a possible adverse effect of medication,” said lead author and ICES scientist Dr. David Juurlink.

“Recent attention has focused on the possible risks of antidepressants in children, but no studies have specifically addressed the safety of SSRIs in older adults, despite the high frequency with which antidepressants are used in this group.”

To explore this issue, ICES investigators linked coroner’s records with patient prescription data, physician billing claims, and hospitalization data for Ontario residents aged 66 years and older between 1992 and 2000 to determine the odds of suicide for people prescribed SSRIs compared to those prescribed a non-SSRI antidepressant. The study included a total of 1,142 suicides in older Ontarians.

The researchers examined the type and timing of antidepressant treatment in the six months before suicide. They found that the majority of patients who committed suicide were not treated with an antidepressant. However, among those who were, the risk with SSRIs was almost five times higher than non-SSRIs during the first month of treatment. This risk persisted regardless of whether the patient had recently been diagnosed with depression or had been receiving psychiatric care for a period of time prior to the therapy. Moreover, suicides of a violent nature (e.g., involving firearms and jumping from heights) were especially common during the initial month of SSRI therapy. However, after the first month of therapy, no heightened risk of suicide with SSRI antidepressants was evident.

“While the initiation of SSRI therapy is associated with a significant increased risk of suicide in this group, the overall risk is low. Therefore, patients who are responding well to SSRI antidepressants should not discontinue therapy, and individuals with depression must not be deterred from seeking appropriate treatment based on our findings,” said Dr. Juurlink.

“It is important to note that our study also indicated that the overwhelming majority of patients treated with SSRIs do not commit suicide. In patients with major depression, the hazards of undertreatment almost certainly outweigh the risks of therapy. The results of this study reaffirm the need for clinicians to reserve SSRI antidepressants for patients with established uses, to monitor patients closely after commencing treatment, and to inform patients and their families of the possible emergence of suicidal behaviours during the initial weeks of therapy.”

The study, “The risk of suicide with selective serotonin reuptake inhibitors in the elderly”, is in the May 2006 issue of the American Journal of Psychiatry.

Author affiliations: ICES (all authors); Departments of Medicine (Drs. Juurlink and Redelmeier), and the Clinical Epidemiology and Healthcare Research Program (Drs. Juurlink and Redelmeier), University of Toronto; Divisions of General Internal Medicine (Drs. Juurlink and Redelmeier), and Clinical Pharmacology (Dr. Juurlink), Sunnybrook Health Sciences Centre.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

FOR FURTHER INFORMATION, PLEASE CONTACT:

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