Friday, June 08, 2012

Juneathon 2012 Day 8 - Exercise and depression

Juneathon 2012 Day 8 - Exercise and depression
Walk - 3.3 miles, Time - 1hr 5min, Weather - high winds with rain

The study in the BMJ on facilitated physical activity as a treatment for depressed adults has already been well discussed and just about every point I would want to make has already been made. But I can't let that stop me,   being late is one of my specialities and the subject of exercise and health is central to this blog.
First of all some background. There is a lot of anecdotal evidence that exercise can affect mood and help people cope with depression and a structured group physical activity programme is recommended by NICE as an intervention for those with subthreshold depressive symptoms. However the academic evidence is scant and the Cochrane Review of 2010 found that when data from  25 trials was combined,  exercise did seem to improve the symptoms of depression, but there was uncertain as to how effective it was, or what the most effective types of exercise were. So it is an area ripe for further study.  A heavyweight study from Bristol University would therefore seem to be just what was needed. 
It is a proper large scale study with 361 adults split into two randomised groups one of whom received normal treatment, the other normal treatment + support with an exercise programme. Their conclusion that the exercise support programme they used (3 face to face sessions and 10 telephone calls with a trainer over 8 months) had no noticeable extra benefit over normal treatment must therefore be taken seriously. But all that it really shows is that a particular type of intervention did not work. It did not show that exercise could not help people with depression and it had no information whether there were differing effects with different types of exercise. 
Unfortunately that was not how it was reported. The news bulletins all reported that exercise made no difference. This was not really the journalists fault because it is very much the line of the press release (upon which all stories were based). However there is a thin line between this and an interpretation that 'scientists prove exercise is no good at all for depression'. Some people who suffer with depression read it that way and reacted with outrage. It seemed as if someone was trying to invalidate their own experience.
Simon Hattenstone is a thoughtful and entertaining writer for the Guardian but his immediate response reads like a howl of pain. You cannot lightly separate a man from knowledge he has gained from his own experience. Unfortunately you also cannot generalise from that experience and think it is the same for everybody. His article was fisked by Pete Etchells, in a way that not only  showed what was wrong with his response but also pointed out some of the limitations of the study itself (it is well worth the read, including the comments). Other good summaries have also been written by Tom Chivers and Martin Robbins
I find this all rather heartening. There was a study the reporting of which made claims that could not fully be supported by the research, there was a kickback and then there was an attempt to make some sense of what was actually said in the initial report. This is good because too often the initial, simplified news headline is repeated and repeated until it becomes accepted as fact. This subject has caused more debate, perhaps because of the  number of people with personal experience who are in a position to write about it, and report itself has been looked at more closely.
This attention might also help some of those who initially reacted with hurt to the news items. Mark Rice-Oxley started his response by saying: "The problem with arguing with science is that it is often an uneven contest, a bit like hitting a steamroller with a stick of rhubarb." But it is not like that at all. He only needs to look at the Responses attached to the article in the BMJ to see how the subject can be engaged and the way the limitations of the study can be exposed. From that it is very clear there is still an awful lot more we need to know and huge scope for further research. The subject is far from settled.
P.S. Any time there is a claim about health in the papers the place to go for context and evaluation is the 'Behind the headlines' service from NHS Choices. Its reporting of this issue was, as ever, excellent.
P.P.S. I should also mention my blogging friend Travelling Hopefully who tackled this subject before me and covers much of the same ground,
P.P.P.S. Today's picture of blurry trees is my attempt at showing how windy it has been.

1 comment:

warriorwoman said...

Thanks for this round up of the relevant reporting. I did find myself quietly outraged as the first headlines came through but I will now enjoy reading the considered responses.