Researchers reported that the risk of serious suicide attempts or death from suicide actually decreased in the weeks after the mostly adult patients started taking the drugs.
And patients who took one of 10 new-generation antidepressants that are under government scrutiny had a lower incidence of suicidal behavior than patients who took older drugs.
The findings challenge the claim that the newer antidepressants are specifically associated with an increased risk of suicide.
In the spring of 2004 the FDA warned that patients taking the newer drugs should be closely monitored for warning signs of suicide, although it stopped short of saying that taking the drugs increases suicide risk.
The 10 drugs identified by the FDA are Prozac, Paxil, Zoloft, Effexor, Celexa, Lexapro, Luvox, Remeron, Serzone, and Wellbutrin. With the exception of Wellbutrin, Remeron, and Serzone, these new-generation medications target the brain chemical serotonin.
The Luvox and Serzone brands have been discontinued in the U.S. but are still sold under the generic names fluvoxamine and nefazodone.
The FDA is conducting a comprehensive review of the research to better assess whether antidepressant use influences depression-related suicide.
Attempts Dropped by More Than Half
The newly published analysis is the first to compare suicidal behavior risk before and after treatment. Researchers reviewed medical, pharmacy, and death records for 65,103 patients from Washington state and Idaho taking antidepressants who were enrolled in a Seattle-based health care plan.
They found that the risk of suicide attempts was highest the month before starting the prescription. The risk of suicide attempts fell in the month following the beginning of drug treatment by more than one-half, the researchers write. Attempts declined even further over the next five months.
There were 31 actual suicide deaths and 76 serious suicide attempts in the six-months following initiation of antidepressant therapy.
The findings are reported in the January 2006 issue of the American Journal of Psychiatry.
"It is clear that the overall risk of a serious suicide attempt or of dying by suicide after starting antidepressants is very low," researcher Gregory E. Simon, MD, MPH, tells WebMD. "Given all the negative publicity surrounding these drugs people might think that suicide is common, but it is really very rare."
The findings also fail to confirm a long-held medical belief that patients are particularly vulnerable to suicide soon after starting drug therapy.
The risk of death by suicide among the study population was not significantly higher in the first month after starting antidepressants than in subsequent months.
"This has been repeated for decades and it is now clinical lore in psychiatry, but it appears not to be true," Simon says.
FDA Warning Revisited
The FDA has been criticized by some who say that it acted too hastily in warning about the potential for suicidal behavior in adults being treated with the new-generation antidepressants. The agency has also required the manufacturers of five of the drugs to warn that the medications could pose a specific risk for children and teens.
Adolescents in the newly reported study attempted suicide four times as often as adults. But, as with the adults, the risk of attempts was highest in the month before treatment and declined after treatment began.
Simon says there were too few children and teens included in the study to determine if this population is uniquely vulnerable.
With regard to adults, Simon points out that the FDA warning simply calls for close observation of people under treatment with antidepressant medications. While he agrees that this is a good idea, he says it isn't because they are at increased risk for suicide.
"Closer monitoring is clearly needed, but we have data which shows that the FDA advisory has resulted in fewer patients being treated with no improvement in monitoring," he says.
American Psychiatric Association spokesman David Fassler, MD, says the new findings are consistent with the emerging research on drug treatment for depression and suicide.
"There is no evidence to suggest that [the newer] antidepressants increase the risk of suicide," he says. "On the contrary, we know that access to comprehensive and appropriate treatment reduces the risk of suicide in patients with depression. The current study is a useful contribution to the ongoing public dialog on this issue."
SOURCES: Simon, G.E. American Journal of Psychiatry, January 2006; vol 163: pp 1-7. Gregory E. Simon, MD, MPH, psychiatrist, Center for Health Studies, Group Health Cooperative, Seattle. David Fassler, MD, child and adolescent psychiatrist, Burlington, Vt.; clinical professor of psychiatry, University of Vermont College of Medicine; trustee-at-large, American Psychiatric Association. FDA Public Health Advisory, June 2005.
By Salynn Boyles
Reviewed by Louise Chang, MD
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