Overprescribing antidepressants: where’s the evidence?
BMJ 2014; 348 doi: https://doi.org/10.1136/bmj.g4218 (Published 30 June 2014) Cite this as: BMJ 2014;348:g4218- Margaret McCartney, general practitioner, Glasgow
- margaret{at}margaretmccartney.com
Is the United Kingdom in the grip of an antidepressants epidemic? We are certainly gripped by an epidemic of the media writing about them. The past few months have seen reports of more antidepressants being used during the financial crisis,1 stories of how many people seem to be taking them,2 and an article in the Guardian by Peter Gøtzsche—a member of the newly formed Council for Evidence Based Psychiatry, which aims “To reduce psychiatric harm by communicating the latest evidence.”3
“It’s hard to believe that so many people have become mentally disturbed and that these prescription increases reflect a genuine need,” said Gøtzsche. He blamed overdiagnosis, conflicts of interest among the writers of the Diagnostic and Statistical Manual of Mental Disorders, and the illegal marketing of psychiatric drugs. He concluded, “Another report said that, amongst people over 65, antidepressants are believed to kill one out of every 28 people treated for one year, because they lead to falls and fractures.”
Is this true? The paper he referred to was a population based cohort study, capable of finding association but not causation.4 And the council said that antidepressant use had increased by 92% in England since 20035; however, it cited the Health and Social Information Centre, which records prescription items rather than prescription amounts.6
Over the past decade GPs have been told to prescribe tablets monthly rather than, as previously, an amount that would last 2-3 months.7 The number of items dispensed is likely to have increased as a result—but it is uncertain, from the data cited by the Council for Evidence Based Psychiatry, whether this means that more people are taking them.
Similarly, a report by the Health Foundation and the Nuffield Trust, which found an increase in antidepressant use during the recession, analysed prescription cost data.8 But it concluded, “We cannot determine whether these trends are based on the same people receiving more medication, or whether they reflect an increase in the number of people receiving antidepressants.” And a study published in 2009 found that the proportion of antidepressant prescriptions given to people with a new diagnosis of depression was constant from 1993 to 2005—making it unlikely that more people with symptoms of depression were treated with antidepressants during that timeframe.9
I have little doubt that overdiagnosis occurs. And I have no illusions about the effectiveness of antidepressants in mild to moderate depression. But big data can mean big problems, and this can pose more questions than it answers. Failing to pay attention to uncertainties and caveats means that we can overshoot the evidence, and this can cause harm through the under-recognition and undertreatment of mental illness.
Notes
Cite this as: BMJ 2014;348:g4218
Footnotes
Competing interests: I have read and understood the BMJ policy on declaration of interests and declare the following interests: I’m an NHS GP partner, with income partly dependent on QOF points. I’m a part time undergraduate tutor at the University of Glasgow. I’ve written a book and earned from broadcast and written freelance journalism. I’m an unpaid patron of Healthwatch. I make a monthly donation to Keep Our NHS Public. I’m a member of Medact. I’m occasionally paid for time, travel, and accommodation to give talks or have locum fees paid to allow me to give talks but never for any drug or public relations company. I was elected to the national council of the Royal College of General Practitioners in 2013.
Provenance and peer review: Commissioned; not externally peer reviewed.
Follow Margaret McCartney on Twitter, @mgtmccartney