Antidepressants may not be as effective in treating depression as healthcare practitioners believe, according to new research.
While they are the most commonly used medication in Australia, with use more than doubling since 2000, this rise has seen no commensurate improvement in outcomes for people with depression.
A recent article published in the MJA reveals several reasons behind the falling effectiveness of the drugs, including an increasing placebo response rate that has led to a narrowing gap between response to medications and placebo.
Authors Dr Christopher Davey and Professor Andrew Chanen, from the University of Melbourne, also cite the manipulation of study findings to inflate the effectiveness of antidepressants, and influencing by the pharmaceutical industry on selective publishing of positive results.
Psychotherapy and adjunctive treatments such as exercise and dietary interventions have been neglected, they add, and doctors should also take their fair share of the blame.
“An unfortunate nexus has developed between diagnosis of depression of any severity and the reflexive prescription of medications as monotherapy, for which the medical profession must accept some responsibility,” they write.
Professor Harvey Whiteford, a population mental health researcher from the University of Queensland, agrees.
“We still don’t have good alignment between the needs of the patient and the intervention which can effectively respond to that. We have an over-reliance on medication and an under-reliance on psychological therapies,” he says.
Professor Anthony Jorm, head of the Population Mental Health group at the Melbourne School of Population and Global Health, blames a “major quality gap” in the treatment of depression.
“We have had no population health gain in depression prevalence despite increases in both antidepressant treatment and psychological therapy,” Professor Jorm told MJA InSight.
“In theory greater uptake should produce a population health gain, but because of a major quality gap we have not seen the expected benefits,” he says.
Combined treatment with medication and psychotherapy, as well as improved diet and increased exercise, would provide greater effectiveness for treating depression, the study authors conclude.
The study was published in the 16 May 2016 issue of the Medical Journal of Australia.