A number of recent research studies have raised questions regarding the efficacy of many commonly prescribed psychotropic medications, including antidepressants. In some studies, these drugs do not perform better than placebo, when the placebo is selected to mimic the side effects that frequently allow participants in "double blind" randomized drug trials to tell whether or not they were given the active drug.
Now a new study adds to concerns by suggesting that antidepressant use may cause harm by significantly raising the likelihood of relapse upon cessation of medication in patients receiving them. In a meta-analysis quantitatively combing data from a number of published studies, Paul Andrews of McMaster University found that antidepressant use increased the risk of relapse from 25% among those not receiving drugs to 42% among those who received antidepressants, as described in a McMaster press release.
They [Andrews and colleagues] analyzed research on subjects who started on medications and were switched to placebos, subjects who were administered placebos throughout their treatment, and subjects who continued to take medication throughout their course of treatment.
Andrews says anti-depressants interfere with the brain's natural self-regulation of serotonin and other neurotransmitters, and that the brain can overcorrect once medication is suspended, triggering new depression.
Andrews, an evolutionary biologist, uses these results as the basis for speculation about the nature of depression and whether it should be conceptualized as a disease or "disorder":
"There's a lot of debate about whether or not depression is truly a disorder, as most clinicians and the majority of the psychiatric establishment believe, or whether it's an evolved adaptation that does something useful," he says.
Longitudinal studies cited in the paper show that more than 40 per cent of the population may experience major depression at some point in their lives.
Most depressive episodes are triggered by traumatic events such as the death of a loved one, the end of a relationship or the loss of a job. Andrews says the brain may blunt other functions such as appetite, sex drive, sleep and social connectivity, to focus its effort on coping with the traumatic event.
Just as the body uses fever to fight infection, he believes the brain may also be using depression to fight unusual stress.
If these authors' view that depression is, in most cases, a natural mechanism to deal with stress, then "treating" it with drugs that short circuit the healing process may be counterproductive in many ways.
As with all new research, we should be cautious about interpreting these results until they are critically examined by other researchers. Like with other research methods, there is often no consensus as to whether a meta-analysis has been properly conducted.
If this study holds up after critical examination, these new results should increase concerns that antidepressants are, at best, radically over-prescribed. Physicians, including primary care physicians who often know little about the subtleties of antidepressant use, often use these medicines as the first, and even only treatment for most depressions. Though knowledge about the danger of relapse when discontinuing these drugs has spread among thoughtful psychiatrists in recent years, this knowledge has often not spread to primary care physicians and others who do most of the prescribing of these medications.
Thus, extant evidence suggests that, these medications should be used carefully. This new study ads to evidence that these drugs should be used sparingly and that, once administered, antidepressants should not be discontinued quickly, but should be gradually tapered over a long time to give the brain's neurotransmitter systems time to adjust.
Current patterns of antidepressant use may be causing serious harm to public health, this and other studies suggest. Thus, the mental health field should seriously reconsider whether antidepressant use should continue to be the first-line treatment for those suffering from depression. If these drugs increase relapse rates while having uncertain efficacy in many cases, they should be used sparingly and with caution.
Alternatively, first-line use of psychological treatment approaches that aid the body's natural coping processes may avoid the problems with antidepressant use, including difficulty in withdrawing from the drugs and increased likelihood of relapse. Alas, the power of the pharmaceutical industry makes such reconsideration difficult. When there are billions of dollars at stake, science and public health often count for little.