In recent weeks, researchers with ties to the drug industry have once again tried to drum up opposition to the FDA's black box warnings on antidepressants for children and young adults. The latest dart came in an Archives of General Psychiatry study in June trumpeting a "persistent decline" in the diagnoses of depression among children and adults in the years after the FDA warned that antidepressant usage in children and young adults can increase the risk of suicidal thoughts and behaviors. As one of the study authors (who by the way consults for several SSRI makers) told WebMD, this proves that the FDA warnings have had dangerous "unintended consequences" and should be repealed.
Not so fast. Leaving aside the contention that a drop in depression diagnoses is a terrible thing -- some bloggers like Philip Dawdy at Furious Seasons argue otherwise -- now comes a definitive new study published in the British Medical Journal, confirming the increased risk in suicidal thoughts and behaviors among young adults taking antidepressants. After examining proprietary data from 372 clinical trials and almost 100,000 patients, the authors (FDA staffers) conclude that the "risk of suicidality associated with use of antidepressants is strongly age dependent. Compared with placebo, the increased risk for suicidality and suicidal behaviour among adults under 25 approaches that seen in children and adolescents." The study also found a smaller, less significant risk in adults between 25 and 64 and that antidepressants actually reduced the risk of suicidal thoughts and behaviors in those aged 65 and up.
Aside from these findings, which largely confirm earlier research, what I found particularly revelatory about the BMJ study was its refutation of the idea (espoused by many psychiatrists) that the increased risk of suicidal ideation among people taking antidepressants comes from a lessening of their depression (which allows patients to entertain and report suicidal thoughts). As the authors note, this "ascertainment bias cannot easily explain the observed age relatedness of the findings or the stronger apparent increase in suicidality in non-depressed psychiatric patients."
The authors go on to note that "these findings support the idea that antidepressant drugs can have two separate effects: an undesirable effect in some patients that promotes suicidal ideation or suicidal behaviour and a therapeutic effect in others that alleviates depression and reduces suicidal sequelae from depression." Doctors, they conclude, should take into account the "age dependent increase in suicidality" in deciding if the benefits of antidepressants outweigh the risks.
Obviously, FDA researchers have an inherent interest in supporting their agency's actions. But it's hard to argue with raw data from 372 clinical trials done over the years by the drug companies themselves (who, after all, have a vested interest in making their drugs look safe).