Friday, 30 December 2011

Britain - the Prozac Nation? Not So Fast...

Oh no! The stress of the recession has turned us into a nation of antidepressant addicts, according to every single British newspaper this morning.

The media coverage has been predictable with lots of scary, context-free statistics, and boilerplate quotes from the usual suspects. No doubt tomorrow we'll see a selection of moralistic op-eds about this.

But not one of the many nigh-identical articles provided a link to the original data, or even a useful description of where one might find it. After contacting one of the NHS organizations named as the source, I managed to track the numbers down.

It turns out that the key figures have been publicly available since April 2011, so I'm not sure why this story appeared in British "news"papers at all. Also, it would have been easy for journalists to link to the source, if they respected the intelligence of their readers enough to do that. I just did it and it wasn't terribly hard to click "Add Link".

On that note, I actually read a bizarre article today criticizing British journalists for providing too many links to their source data... if only.

Anyway, the data. Ben Goldacre has already written an excellent piece on this (in fact, he wrote it back in April 2011, curiously enough...see above), but here's some more detail.

First off, the data are all about antidepressants, not depression. A crucial distinction, there, because nowadays, antidepressants are widely used for all kinds of other things. Everything from other psychiatric disorders like anxiety and OCD, to non-psychiatric stuff like back and joint pain, premature ejaculation, and menopausal hot flushes.

We can't tell how much of the antidepressant use was for depression. But there are clues suggesting that a lot of it wasn't. It turns out that the second most popular antidepressant (after citalopram) was the very old drug amitriptyline, with nearly 9 million prescriptions per year - or 20% of the total.

Nowadays amitriptyline is rarely used for depression, because newer, less toxic alternatives are available. However it is used, in low doses, to treat chronic pain. So I suspect that pain accounts for a large % of amitriptyline use. That would also explain why the cost to the NHS per prescription of amitryptiline was by far the lowest of all antidepressants: low doses are cheap.

How about the increase over time?

The newspapers are correct that antidepressant use rose from 33.9 million prescriptions in the year 2007/8, to 43 million in 2010/2011. That's a 28% rise over 3 years. However, if we go 3 years further back to the equivalent 2004/5 Prescription Cost Analysis, we find that antidepressant prescriptions were 28.9 million. So they rose 17% in the 3 years before 2007/8, long before the recession was on the horizon.

The recent 28% rise, in other words, is unlikely to be related to the recession, at least not entirely.

We also know(1,2) that the number of antidepressant prescriptions per person has been rising over the past several years in the UK. So the increase in prescriptions might not even mean more antidepressant users - it might just mean that the same number of users are using more each. (And that could mean anything, including that bureaucracies are saving money by prescribing for shorter periods).

One study found that there was no increase in the number of people taking antidepressants for depression from 1993 to 2005, with all of the rise in prescriptions over that period being a product of more prescriptions per person.

Another study did find a true rise in users from 1995 to 2007, albeit lower than the raw figures would suggest, but those figures were limited to a particular part of Scotland and it wasn't just about depression - it included all other uses of these drugs as well.

Overall, it's just impossible to know, from these data, whether there's been a true increase in antidepressant use for depression in recent years. The most we can say is that there might have been one, and if so it might have something to do with the economy.


Doriannevergreys said...

Not to mention the fact that a significant number of people do not take their prescription medications anyway... So what does all this mean?

Bernard Carroll said...

Dorian makes a good point. In the 1990s patients in Britain took their prescribed antidepressant drugs for very short periods. The median time to discontinuation was around 30 days, and by 60 days 70% to 80% had quit. That is called voting with your feet. See PubMed ID # 10837883.

Neuroskeptic said...

Right. It's hard to study that, although it ought to be possible if you could compare prescriptions against drugs actually sold - although even that wouldn't tell you how many went into people's stomachs as opposed to into the bin...

Ivana Fulli MD said...

Doriannevergreys, Bernard Caroll,

"a significant number of people do not take their prescription medications anyway"

"That is called voting with your feet."

Sorry to play also the boring littlebrainy but this in itself is a problem: cabinets filled with free drugs paid by social security that can be used for an overdose to kill oneself and sometimes the children also.

On the contrary, some clients have withdrawal symptoms and it takes a lot of time and reassurance to be free from the drugs because many psychiatrists prescribe it for too long and some clients are observant.

Anyway Dr Ben Goldacre is depriving us of his Bad Science friday editorial to write a book about Big Pharma and it will be interesting read.

NB: I am not alone to think that amitryptiline is sometimes much more efficient than the prozac and followers antidepressants. I think also great help at a low dose in withdrawal from benzodiazepines in elderly persons.

Neuroskeptic said...

Oh, just thought of another possible explanation for rise in prescriptions - polypharmacy. I don't have any stats, but it seems widely accepted that this is becoming more common nowadays.

ivana Fulli MD said...

I remember also something else on the topic:

A friend of my youth , a psychiatrist - we trained together to become researchers in psychopharmacoly -

and he ended up working for Big Pharma.

he tols me that one of the first lesson he received was:

We as an industry are like the mustard makers: we make more profit with the mustard left on the plate than with the part of it who goes into the client with the pork meat.