Research by scientists at Aberdeen University is challenging the wide-spread assumption that doctors in the UK are dishing out anti-depressants far too readily, and suggests that they are actually being underused instead.

The common belief that antidepressants are being over-prescribed is largely down to the fact that the number of prescriptions for them has rocketed over the last 10 years, more than trebling in Scotland with similar growth rates observed around the globe.

However, when researchers took a closer look at anti-depressant prescribing activity in the Grampian area, which they believe is also representative of GP behaviour elsewhere, they found an altogether different scenario, which showed that only a very small proportion of patients were handed such drugs for no reason.

A key aim of the study – published in the British Journal of General Practice - was to investigate whether patients who did not meet the criteria laid out in national guidelines were unnecessarily being given antidepressants, which are also often used to treat pain, but it found only three such cases out of a total of 897 patients taking part in the survey.

In fact, the findings showed that many patients who qualified for treatment with antidepressants were not being given them, adding further weight to the theory that the condition is significantly under-diagnosed. “Our study showed that GPs did not arrange treatment for about half of the patients who filled in our questionnaires and who had significant symptoms of depression because they did not detect the illness at that visit,” explained study lead Professor Ian Reid.

And this problem, the researchers claim, is in danger of being compounded by new government targets in Scotland set to reign in the number of antidepressant prescriptions by 10%, perhaps a reaction to what is believed to be a situation where they are being handed out too freely as well as a drive to boost the use of non-drug-based therapies.

Satistics of 'limited' use
According to Professor Reid, the belief that antidepressants are being over-prescribed is being fuelled by the limited way statistics are currently used to monitor the situation, as, he says, they are only based on prescription volume and do not provide any information on differences in dose or duration of therapy, for example.

“As the statistics currently measure numbers of antidepressant prescriptions, crucially, they don’t tell us how many people are taking the drugs. If antidepressant doses increased, or the duration of treatment lengthened, the prescription statistic would rise without any change in the number of people being treated,” he explained.

Furthermore, he points out: “Depression is under-treated wherever researchers take the trouble to look,” and “if the rate of missed depression is significant - and international surveys bear this out - then correcting this would increase the prescription volume again”.