Outcry over study claiming antidepressants are ineffective

A controversy in the scientific community over recent claims antidepressants can be ineffective at treating depression has highlighted the difficulties in understanding mental health conditions.

One of the prevailing theories focuses on serotonin. Depression has been linked to a lack of serotonin, which is involved in transmitting emotions to the brain.

Claims that depression has no link to a chemical imbalance in the brain related to serotonin, casting doubt on the need for antidepressants, have sparked fierce reaction.

A study by psychiatrists Joanna Moncrieff and Mark Horowitz in the journal, Molecular Psychiatry, in July concluded there was no proven link between a lack of serotonin and depression.

The authors said it queried the underlying assumption behind the use of antidepressants, which are mostly developed to alter serotonin levels, undoing a theory that for decades had acted as a framework for research.

The study is based on several previous publications, but quickly attracted criticism, particularly its presentation by Moncrieff, known for her scepticism towards biological explanations of depression and her radical stance against the pharmaceutical industry.

“I’m broadly in agreement with the authors’ conclusions ... though I lack their adamantine certainty,” psychiatrist Phil Cowen said on the Science Media Centre website.

“No mental health professional” would endorse the view that a complex condition like depression “stems from a deficiency in a single neurotransmitter”.

Some peers have questioned the methodology, which measured an indirect trace of serotonin rather than taking direct measurements of the molecule.

Moncrieff, who wants to break with what she calls “mainstream” psychiatry, believes the serotonin theory still occupies an important, albeit less prominent, place in the profession.

“Even if leading psychiatrists were beginning to doubt the evidence for depression being related to low serotonin, no one told the public,” the British psychiatrist wrote on her blog.

Moncrieff’s undermining of the serotonin theory to argue against current antidepressants, going beyond the conclusions of her own study, has sparked vehement criticism.

Swiss psychiatrist Michel Hofmann said her study was “serious” and contributed to expert debates about depression.

“But I don’t think it is an article that should have any impact in the short term on the prescription of antidepressants,” he said.

Moncrieff warned that antidepressant treatment should not be suddenly interrupted.

But for her, the benefits of a course of antidepressants are doubtful if it is based on a discredited theory. –