Tuesday, January 20, 2015

Is CBT Better Than Other Therapies?

Of all the "talk therapy" modalities in use today for treatment of common psychiatric disorders (such as OCD, anxiety disorders generally, and depression), probably none is more agressively promoted than Cognitive Behavioral Therapy. As I point out in my forthcoming book, the history of psychiatry is basically a history of fads, and as some fads (e.g., Freudian analysis) fall by the wayside, others (Gestalt therapy, transactional analysis, acceptance and commitment therapy, behavioral activation, and many others) come to take their place. The fad du jour happens to be CBT.

A fundamental tenet of the cognitive model of psychopathology is that cognitive change is central to treating psychological disorder. Modification of maladaptive cognition is core to CBT. The Beck Institute website puts it this way:
When people are in distress, their perspective is often inaccurate and their thoughts may be unrealistic. Cognitive behavior therapy helps people identify their distressing thoughts and evaluate how realistic the thoughts are. Then they learn to change their distorted thinking. When they think more realistically, they feel better.
The goal of CBT is to help the patient learn to identify cognitive distortions and practice reframing them in a more useful way, thereby reducing the patient's reliance on "bad coping skills" like arbitrary inference, selective abstraction, over-generalization, exaggeration (e.g., "catastrophizing"), and minimization. This is a gross simplification of CBT, but it goes to the essence of what gets done in therapy.

CBT has been criticized (appropriately, I believe) on theoretical grounds for its slavishly rationalist bent and its insistence that mentally ill people can fix their problems with what amounts to exercises in clearer thinking. M.B. Shapiro Award winner Chris Brewin (University College London) questions the idea that challenging a person's thoughts leads to changes in feelings and behaviors. He suggests that human cognition actually draws from multiple memory systems and personal-knowledge stores, not all of which are open to introspection. Teasdale (in this book), along the same lines, contrasts “propositional” meanings (which are semantic and declarative) with “implicational” meanings (holistic meanings reflecting the “felt sense” of experience, thus tied to emotion), and questions whether the latter can be assailed with mere logic. Someone suffering from depression isn't necessarily interested in having his logic proved wrong, or being told that every problem can somehow be reduced to a distortion in perception. One of the signature features of mental illness is the convincing illusion that everything you're thinking is 100% real and accurate, even when you're delusional. Indeed, depression is often (subjectively) a feeling of experiencing reality too accurately.

But even in the case of psychosis, it sometimes happens that the patient understands (in his conscious mind, on a logical level) that the FBI isn't really monitoring his brainwaves with listening devices concealed to look like household appliances, yet the feeling that the FBI is "listening" is too strong to ignore. This is the problem CBT can't address (and is why CBT hasn't fared particularly well in schizophrenia trials). You have to be capable of reasoning effectively in order to make use of CBT. In fact, you have to be a high-functioning (not stuporous), motivated, rationality-driven person, and be able and willing to make lists and do homework exercises, in order to get the most out of CBT. You might not be any of the above, if you're profoundly depressed. You might not be any of that if you're not depressed!

Also, sometimes depression is situational, and barring a change in situation (which may not be possible; e.g. if someone died), there's only so much that can be done. If you're grieving over a health situation (cancer), a death in the family, bankruptcy, prison time, etc., you probably aren't ready to have a CBT Pollyanna show you positive-thinking tricks.

In Mindfulness and Acceptance: Expanding the Cognitive Behavioral Tradition (Guilford, New York, 2004), Stephen C. Hayes argues that three “empirical anomalies” exist in the CBT outcome literature. First, component analyses fail to show that cognitive interventions provide added value to therapy. Secondly, CBT is often associated with rapid, early improvement in symptoms, occurring well before any CBT techniques could have been put in practice. Thirdly, measured changes in cognitive mediators (the thoughts and beliefs underpinning the patient's disorder) do not seem to precede changes in symptoms. Richard J. Longmore and Michael Worrell reviewed the literature on these points and found no empirical support for the second criticism by Hayes, but did find substantial evidence in favor of the first and third criticisms.

Cuijpers et al. in 2010 found substantial reason
to suspect publication bias in 175 talk-therapy
trials, most of which were CBT trials.
Notice the asymmetry in this funnel plot.
I won't belabor the issue (since Longmore and Worrell do such a wonderful job on this particular subject), but it's been shown dozens of times, in component factor studies, that the cognitive ingredients of CBT add no demonstrable value (that is, the specific features of CBT can be omitted without adversely affecting outcomes). In fact, more broadly, as Bracken et al. (2012) point out, "The evidence that non-specific factors, as opposed to specific techniques, account for nearly all the change in therapy is overwhelming." According to Bracken:
What emerges from the evidence is that non-specific factors (client variables, extra-therapeutic events, relationship variables and expectancy and placebo effects) account for about 85% of the variance in therapeutic outcomes across the psychotherapy field. In particular, the relationship between therapeutic alliance and outcome seems remarkably robust across treatment modalities and clinical presentations.
Proponents of CBT often point to the massive number of studies showing it to have strong efficacy, but frankly, the studies are subject to many valid criticisms (involving researcher allegiance, lack of a proper placebo arm, and much else), and there is reason to suspect widespread publication bias in this segment of the literature (as in so many others); see accompanying graphic.

Cognitive Behavioral Therapy is effective for many people. So are other therapies. The issue isn't that CBT has no value, but that it's been oversold, and isn't the right tool for every job. CBT can't be said to be superior to other treatments for depression. It's relatively ineffective for schizophrenia and not well supported for bipolar. Even when it works, the effect size is highly variable. See this meta-analysis by Lynch, Laws, and McKenna (2010) for details.

I'm finishing a 113,000-word mental illness memoir that has a lot to say about psychotherapy, drugs, depression, mania, schiophrenia, schizoaffective disorder, and recent trends in psychiatry. To find out more about the book and how to get free sample chapters, add your name to the mailing list and return to this blog often. Thanks!