Wednesday 28 April 2010

More drugs!

Although an American publication this year alluded to the message, "Drugs, just say no!" as discussed below, there's new news.

The British Medical Journal last month published a clinical review paper on, "Long term treatment of depression with selective serotonin reuptake inhibitors and newer antidepressants."

What did it show us?

It showed us 3 things.

1) We're prescribing more antidepressants.

They assume this is because people are prescribed them for longer (because that's what they found, so they're right). The assumption is flawed, though. We prescribe more antidepressants in the UK and USA than we did in 1993 because over the last 17 years prescribing practice has changed.

People with generalised anxiety disorder, adjustment disorder, post traumatic stress disorder and somatoform disorders used to get pretty rubbish drugs. If you had such a problem, with "neurotic" and not "psychotic" problems, and weren't clinically depressed, you often didn't get an antidepressant or antipsychotic (since you're not depressed or psychotic) so got an anxiolytic. Diazepam. Or another benzodiazepine of choice. They were liked because they worked and melted away distress well. Then, years on, problems emerged and subsequently "antidepressant" medication is commonly used in the management of anxiety states. Anxiety states often endure, hence such medication's needed for a long, long time.

Use of antidepressant medication's gone up not necessarily through changes in management of depression, but because "neurotic" disorders are managed with such medication now, instead of dishing out nothing or benzodiazepines.

2) If you continue on medication, you do better

Relapse rates are lower. Antidepressants drugs reduce the rate of relapse, significantly. Hurrah!

The drugs also cause side effects which are common (e.g. at best 24% and at worst 80% of people on antidepressants developed sexual dysfunction).

Stay on the drugs, but get side effects most of the time. Hmmmm.

How many do you need to treat to prevent relapse? They looked at that, too. 4. So for every 4 patients you keep on an antidepressant long term, 3 get no benefit and 1 won't experience a relapse they otherwise would. 3 have no benefit but all the side effects, 1 has benefit and side effects. Hmmmm.

3) The title lies

"Long term treatment of depression with selective serotonin reuptake inhibitors and newer antidepressants" is misleading. It suggests that the paper is about people with depression being on antidepressants long term and although most have serious/unpleasant side effects and for 75% it won't help, for 25% it will be beneficial.

Sadly not.

To their enormous credit, the authors do 'fess up to this. This is because the published papers have significant bias. Rather than taking people with depression, half having antidepressants and half having placebo, then seeing how they do over time (a randomised controlled trial), the studies reviewed were "discontinuation trials." This means that the (usually drug company sponsored) research involved getting a group of people with depression and giving them an antidepressant. Any who didn't respond are then excluded. So of your 100 depressed patients, it may well be that half got better anyway and a third didn't benefit from the drug, so only 10 patients progress through to the trial. What the "discontinuation" bit means is that the researchers then discontinue the antidepressant medication in half the people it's helping and swap them onto placebo.

So a more accurate take on this very good and detailed systematic review of 31 trials, mainly/all discontinuation trials, is :

"In patients with depression, who respond well to an antidepressant, continuing the antidepressant over a longer time (e.g. 12 months) can reduce risk of relapse for 1 in 4 patients."

It's not quite as catchy a headline, though.

Meh, maybe the drugs still don't work quite as well as we'd wish, or as pharmaceutical companies would lead us to believe. But at least if I've patients with chemical clinical depression, who respond to an antidepressant, and have a relapse, then this paper supports the ongoing use of an antidepressant over the longer teerm (over years). And that this works well, halving the risk of relapse. That's good news. It's certainly something folk will welcome, who've shown clearly that the antidepressants work well for them, as robust evidence that it's worth continuing and shouldn't be taken off them!

1 comment:

Unknown said...

*hugs box of venlafaxine*

I get sod-all side effects from anti-depressants. Never had a single one.

Anti-psychotics, otoh (holds up garlic and crucifix).