Study: Antidepressant Suicide Risk Not Due to Drugs

Patients on antidepressant drugs run a higher risk of suicide in the first few days of therapy, but the risk is similar with any of the most popular mood-lifting drugs and may be rooted not in them but in the underlying depression, a study said on Tuesday.

Patients on antidepressant drugs run a higher risk of suicide in the first few days of therapy, but the risk is similar with any of the most popular mood-lifting drugs and may be rooted not in them but in the underlying depression, a study said on Tuesday. The report, published in this week’s Journal of the American Medical Association, was designed to find out if drugs called selective serotonin reuptake inhibitors were associated with a higher suicide risk than other mood lifters. The serotonin-related drugs work by providing more of that brain chemical, a substance thought to regulate depression and anxiety; but the use of such drugs has triggered suicide-related lawsuits and specific concerns about their impact on adolescents. Researchers at Boston University said they looked at data on nearly 160,000 users of four antidepressants in England from 1993 to 1999. The four drugs were fluoxetine, paroxetine, amitriptyline and dothiepin, the last two part of an older class of antidepressants called tricyclic drugs that also act on nerve cells in the brain. The researchers reported they found nonfatal suicidal behavior was four times more likely to occur within 10 days of when any of the drugs was first prescribed — and three times more likely in the following 19 days — than was the case after the patient had been on a drug for three months. “Similar associations were present for all four of the study drugs,” the report said “We think the most likely explanation for this finding is that antidepressant treatment may not be immediately effective, so there is a higher risk of suicidal behavior in patients newly diagnosed and treated than in those who have been treated for a longer time,” the authors said. “It is also possible that this observation reflects patients starting to take an antidepressant when their depression, which naturally fluctuates over time, is at its worst…” they added. “We cannot exclude what we think is a less likely possibility, namely that the drug itself ’causes’ depression to worsen rapidly, thus leading to suicidal behavior.” PERSUASIVE EVIDENCE But whatever the reason the study offers persuasive evidence that the effect is the same for all four antidepressants, they said. The U.S. Food and Drug Administration earlier this year asked the makers of 10 different antidepressant drugs to include label warnings recommending close observation of adults and children for worsening depression or the emergence of suicidal tendencies. The authors also aid that “based on limited information, we also conclude that there is no substantial difference in effect of the four drugs on people aged 10 to 19 years” though “some important difference in effect cannot be ruled out based on this study.” The school’s Boston Collaborative Drug Surveillance Program said the research was carried out with its own general funds and not money from drug companies. (Source: Journal of the American Medical Association: Reuters Health News: Michael Conlon: July 2004)