Drugs not linked to more suicides
DALLAS – A newer class of anti-depressants – controversial because of fear they may fuel suicidal behavior – might not be any riskier than older drugs, a study of United Kingdom patients has found.
Risk of suicide or suicidal behavior was high in the first month of therapy – and dramatically so in the first nine days – no matter which of four drugs patients took, Boston University scientists reported today in The Journal of the American Medical Association.
The 1993-99 study drew from nearly 160,000 first-time anti-depressant users who had filled a prescription for any one of four drugs. The drugs were the United Kingdom’s four most prescribed anti-depressants.
“We found there really was no difference between the four,” said Susan Jick of the Boston Collaborative Drug Surveillance Program, one of the study’s authors.
Prozac and Paxil were the drugs in the controversial class of medicines, called selective serotonin-reuptake inhibitors, or SSRIs. In March, the U.S. Food and Drug Administration asked drug companies to warn the public that patients using SSRIs should be monitored closely, especially at the beginning of therapy, for suicidal feelings or deepening depression.
The other drugs in the study, from an older class of anti-depressants called tricyclics, were Elavil and a drug known generically as dothiepin, which is not available in the United States.
The researchers also found that there did not appear to be any difference among the drugs in their effects on youths ages 10 to 19, a topic of widespread public debate.
“I think this actually begins to address the problems people have in assessing suicide risk with anti-depressant medicines,” said Dr. Madhukar Trivedi of the University of Texas Southwestern Medical Center at Dallas. “It is a very good study.”
The research focused on about 570 patients who had killed themselves or displayed suicidal behavior, comparing them with more than 2,200 others who used the drugs without such problems. Suicidal thoughts or behaviors were four times as likely to occur within nine days of filling a first anti-depressant prescription – and almost three times as likely from day 10 to 29 of the prescription – as they were more than 90 days after filling the prescription.
Risk of actual suicide was 38 times as high during the first nine days of anti-depressant use, and five times as high during the rest of the first month, compared with more than 90 days out.
Based only on that, Trivedi noted, doctors can’t say there’s a link between the medicines and suicidal behavior. “What we can say is that when patients are so sick that they start an anti-depressant, that the first month is fraught with risk.”
The findings offer a vital public health message, Jick said: “People who have recently started anti-depressants need to be monitored very carefully.”
The scientists also studied patients who had stopped use of one of the drugs, to see whether some type of withdrawal occurs that may be related to suicidal thinking or behavior, but found no evidence for such a link.
“The findings … provide useful data in what is still a somewhat messy situation,” Dr. Simon Wessely and Robert Kerwin, of the Institute of Psychiatry in London, wrote in an editorial accompanying the study. “Public anxiety fueled by media reports has transferred itself to the already nervous regulatory authorities, and it is unlikely that this study alone will restore confidence.”
The FDA’s warning might have led depressed patients to assume that starting medication is a risky endeavor that should be avoided, Trivedi said. But if depression is not treated, “the danger is profoundly higher than the danger they face when they start the anti-depressant.”