The updated NICE guideline for depression is just out. Here is what it has to say about St John’s wort:

Although there is evidence that St John’s wort may be of benefit in mild or moderate depression, practitioners should:
• not prescribe or advise its use by people with depression because of uncertainty about appropriate doses, persistence of effect, variation in the nature of preparations and potential serious interactions with other drugs (including oral contraceptives, anticoagulants and anticonvulsants)
• advise people with depression of the different potencies of the preparations available and of the potential serious interactions of St John’s wort with other drugs.

Funny that. In the last issue of EBMH, Edzard Ernst, the professor of complementary medicine who has become the bête noire of the alternative medicine crowd was less dismissive. Reviewing the latest Cochrane update he concludes that there is now plenty of evidence demonstrating that SJW is an effective antidepressant and if you can avoid herb-drug interactions, it may be safer than conventional drugs. So why don’t we recommend SJW for depression?

I have written about SJW here before and was less than complimentary (ouch!). My scepticism was similar to the NICE position: you can’t be sure what you are getting, and patients thinking that it’s not really a drug mix it with prescription medication and run into trouble. Perhaps, however, there is more to it than that. Given the rather murky history of clinical trials and marketing with conventional antidepressants and the often marginal benefit over placebo it does seem as though when it comes to evidence we hold St John’s wort to a higher standard. Trawl through the rapid responses of a trial involving SJW and you will find a degree of nit-picking that is rarely seen with the SSRIs. This type of reader or reviewer bias is not much discussed and competing interest statements rarely include declarations of inherent prejudice. In this editorial for Clinical Evidence, Professor Ernst criticises the knee-jerk assumption that if a clinical trial of a complementary medicine shows efficacy it must be a flawed trial. So is St John’s wort being treated unfairly? The answer, I think, has to be yes.

Oh dear, Lord Layard will not be happy, but Zoe Williams will be. It looks like the wheels may be coming off the UK government’s plans to provide cognitive behavioural therapy for all - Improving Access to Psychological Therapies. With reports that there aren’t enough suitably-qualified therapists to go around and that funding may be in jeopardy, The Observer reports:

A flagship government strategy to train an army of therapists to get the nation off antidepressants and into work could be dramatically scaled back amid claims it is experiencing problems. More here.

I wonder if there is any provision for psychotherapy in David Cameron’s ‘Get Britain Working’ programme?

With the recording of a narrative verdict following the inquest, the death of Kerrie Woolterton is once again making headlines. I wrote about this case of a young woman presenting with self-poisoning and refusing treatment one year ago, in a blog which attracted some thoughtful comment. The coroner stated: “She had capacity to consent to treatment which, it is more likely than not, would have prevented her death. She refused such treatment in full knowledge of the consequences and died as a result.” Sheila McLean, a Professor of Law and Medical Ethics, concurs with this view and clarifies the law in a commentary for the BMJ. She is correct, of course, in highlighting that if Ms Woolterton was thought to have capacity to make a decision about her treatment at the time of assessment the presence of an advance directive was indeed irrelevant.

Yet I still find the outcome of this case troubling. We are relying on details of events reported by the media, but given the context of this woman’s suicide would the presumption that she had capacity to decline treatment be so straightforward? Professor McLean makes the point that the presence of mental illness or indeed personality disorder is not in itself evidence of a lack of capacity. I would agree, but that does not mean they have no potential to influence or impair decision-making. Ms Woolterton had repeatedly presented after self-poisoning and would have known that treatment would be offered. That she still chose to call an ambulance to take her to hospital, albeit that she stated she was only seeking comfort and company, suggests to me a degree of ambivalence.

Key to the concept of capacity is the determination that a person understands the information relevant to a decision, and can use or weigh that information as part of the process of making the decision. As a legal concept that’s pretty clear but in a clinical setting where so many factors can be at play that determination can become murky. And of course, people often do not say what they mean or mean what they say.

In the last year I have discussed this case with a range of clinicians, and although the majority state that given this scenario they would have questions about the patient’s capacity and opt to treat them in their best interests, opinions are mixed. So the outcome (life or death) may have as much to do with our variable views as any objective measure of capacity which makes me uneasy. Vivienne Nathanson, head of science and ethics at the BMA, said the Mental Capacity Act had clarified the law for doctors. Maybe so, but it hasn’t made challenging dilemmas such as this any easier to resolve.

More antidepressants please…and bump up the Ritalin too. That seems to be the suggestion from this study published by the National Bureau of Economic Research in the US, making a link between new drug treatments for depression and ADHD and falling crime rates (Hat tip: The Economist).

Since the 1990s violent crime rates have declined markedly (no, it’s true, really), especially in the US. Criminologists have struggled to explain the trends as the usual suspects seem to have had little impact. So enter the economists with their alternative explanations, such as Steven Levitt (he of Freakonomics fame) presenting evidence that legalizing abortion in the 1970s led to a decline in the number of young people at risk of criminality, thus reducing crime rates.

In their provocative paper, A Cure for Crime?, Dave Marcotte and Sara Markowitz use data on international drug sales and crime rates as well as more detailed US data from the National Comorbidity Study (showing that in those with a mental disorder the percentage receiving treatment has increased from 20 to 33%) and national prescribing rates to show that ‘the countries with the largest declines in crime rates in the 1990s were almost exclusively those with the fastest growth in SSRI sales’. Details of the analysis are in an ungated preliminary version of the paper here. To control for overall improvements in health care they also looked at the impact of the non-psychotropic medicines, statins and COX-2 inhibitors which have also seen a rapid growth in prescriptions, but here there was no effect. They found that that increased prescribing of psychiatric drugs, notably SSRIs and stimulants (Ritalin), were associated with a reduction in violent crime and go on to conclude:

“Our evidence suggests that, in particular, sales of new generation antidepressants and stimulants used to treat ADHD are associated with rates of violent crime, with weaker evidence that anti-psychotic medications played a role in declining crime rates. The magnitude of the elasticities estimated here are clearly small. We estimate that a one percent increase in the total prescription rate is associated with a 0.051 percent decrease in violent crimes. To put this in perspective, doubling the prescription rate would reduce violent crimes by 5 percent, or by about 27 crimes per 100,000, at the average rate of 518 crimes per 100,000 population. While doubling the prescription rate seems like a large change, it has been estimated that 28 percent of the U.S. adult population in any year has a diagnosable mental or addictive disorder, yet only 8 percent seeks treatment (USDHHS 1999). Doubling the treatment rate would still leave a substantial portion of the ill untreated.

From the beginning to end of our panel, prescriptions per visit increased by 41 percent. Our elasticity estimates imply that this would reduce the total number of violent crimes committed by about 35,000. In fact, the total number of violent crimes reported to police declined by 300,000 during the period. Our estimates imply that just under 12 percent was due to expanded mental health treatment.”

Medical journals tend be dismissive of natural experiments and ecological studies such as this, considering them pretty weak evidence. But given that questions like this are never going to be answered by randomized controlled trials, if the methods are robust some freakonomic epidemiology may be just what we need.