As a panellist on Moral Maze tonight (Radio 4, 20.00) I will be discussing some of the implications of a recent LSE report on mental illness and treatment in the UK. I am looking forward to the programme, but with some trepidation, as I find myself ambivalent about both the report and the issue in general.
There is good evidence of high rates of untreated mental illness in the UK. The LSE report suggests six million adult sufferers from depression and anxiety conditions, plus 700,000 children with these conditions or other problem behaviours, but that only a quarter of each group is being treated. The links between mental illness and both physical impairment and low life satisfaction also seems strong. And the Cognitive and Behavioural Therapy (CBT) intervention promoted in the LSE report has three strong benefits: apparently impressive success rates, relatively low costs and (unlike drug therapies) few potential adverse side effects.
My interest in the science of brains and behaviour also inclines me to believe all of us need to be aware of our cognitive frailties and to recognise how easy it is to fall into ways of thinking and acting which are bad for us (and for those around us).
So, why the ambivalence? One concern is the flip side of the LSE’s evidence about prevalence. If getting on for one in five adults and one in ten children suffer from mental illness, what does this mean for the divide between normal and ill, and what does it tell us about wider society?
CBT is often combined with drug therapies and the view that a sustained feeling of sadness, anxiety, inadequacy or over-stimulation should be seen as a medical condition requiring treatment is one which has been pushed long, hard and very successfully by the pharmaceutical industry. Yet, remarkably, the theory on which most drug treatments are based - that moderate mental illness is caused by a chemical imbalance in the brain - remains unproven. The drug industry uses the fact that some people get better after being given brain altering chemicals as evidence, but this is like saying a headache is caused by an absence of aspirin. Furthermore in relation to the major growth areas for diagnosis and treatment, there continues to be an absence of evidence for drug interventions being more successful than placebo with side-effects.
As the LSE report does not discuss drugs I don’t know its authors’ views about this kind of treatment. But its medical model suggests that if the chemicals did work, the authors would be reconciled to nearly one in five of us taking them.
On occasion, the LSE report seems closer to advocacy than objective research. A core argument is that mental illness is more curable than long term physical conditions. To an extent this depends on what we mean by curable and whether the aim of an intervention is to cure or to enable the patients to manage their illness, but the claims made in the report for CBT also rely on some hidden assumptions.
The summary (and press release) state:
‘…..the costs of psychological therapy are low and recovery rates are high. A half of all patients with anxiety conditions will recover, mostly permanently, after ten sessions of treatment on average. And a half of those with depression will recover, with a much diminished risk of relapse. Doctors normally measure the effectiveness of a treatment by the number of people who have to be treated in order to achieve one successful outcome. For depression and anxiety the Number Needed to Treat is under 3. In the government’s Improved Access to Psychological Therapy programme, outcomes are measured more carefully than in most of the NHS, and success rates are much higher than with very many physical conditions’
By definition chronic diseases cannot be cured so it hardly surprising that mental health interventions achieve a better rate or recovery. But when assessing the long term cure rate for CBT (about 30%) we have to include two factors which much less often apply to long term physical illness: over-diagnosis and the scope for recovery without treatment.
In relation to the former, while most chronic conditions are diagnosed through objective physiological or chemical tests, mental illness is based more on subjective reporting. Also, there are various work and benefit-related incentives for people to seek a medical diagnosis. Furthermore, while few people want an unnecessary physical treatment many people (whether or not they are ‘ill’) might welcome the structured advice offered by CBT.
In relation to recovery, one of the many continuing imponderables about mental illness – including quite acute problems – is the course of illness. Unlike chronic physical conditions, many people seem to get better naturally (or find an effective way of coping without treatment), and avoid future episodes.
If we were to assume that one in five diagnoses of mental illness was inaccurate and that, say, one in ten treated patients would have got better anyway (a conservative estimate), and if we assume that these two groups are likely to be over-represented in the 30% for whom CBT ‘works’, then the implied level of efficacy falls dramatically.
The slightly clumsy use of statistics in the report stirs my other concern. I am currently reading Robert and Edward Skidelsky’s book ‘How much is enough – the love of money and the case for the good life’ (I am chairing father and son here at the RSA tomorrow). As the book makes clear, millions of us work longer hours than we need to primarily to buy goods which we then consume in a compressed leisure time which is much less satisfying than it could be if we had a different outlook on life. Such behaviour could be portrayed as a form of collective madness (particularly when – notwithstanding the ‘lump of labour’ fallacy – a better distribution of work would be good for economy and society). How many of the six million adults and 700,000 children are ‘mentally ill’ directly or indirectly as a consequence of these dysfunctional social norms and patterns?
We don’t respond to obesity primarily by demanding mass liposuction but by focusing on the social and economic factors which seem most likely to be fostering over-eating. Although Richard Layard – the driving force behind the LSE report – has a distinguished record in promoting debate about the wider social conditions for happiness and wellbeing, the publicity attached to his report directs attention to an individual medical answer rather than a wider inquiry into why modern living makes so many people so sad and worried.