One of the big questions in the field is what should you do if an evidence based treatment is not successful. If we look at binge eating as a behaviour, and thus covering the diagnosis of bulimia nervosa (BN) and binge eating disorder (BED), then the “treatment of choice” would be Cognitive Behavioural Therapy (CBT). Yet we know that not all people recover using CBT and some relapse after treatment ends. It has been suggested that an ‘additive’ design, where other therapy protocols are added onto the treatment of choice, may be useful to examine.
McIntosh et al. (2016) from Christchurch have recently published a paper in Psychiatry Research looking at adding two additional treatments to CBT for binge eating.
The first protocol is CBT-Appetite. This treatment assumes that diminished recognition of hunger and fullness cues are a maintaining factor in binge eating. The focus is on monitoring appetite rather than food intake as in traditional CBT. Patients are taught to eat in response to moderate hunger and to stop eating when moderately full. Food choices are encouraged around foods with greater volume and lower energy density and greater satiety potential (e.g. including protein throughout the day and choosing lower GI carbohydrates). Patients learn to recognize and not respond to emotional and situational triggers for eating. The reference given for this treatment is a chapter by McIntosh et al. in Wilson and Latner (2007) ‘Self-Help for Eating and Obesity’. I haven’t read the chapter (but will) but I am really curious as to whether or not it uses a dietitian in its delivery. Much of what is described in the article are core dietetic interventions for binge eating.
The second additional protocol looked at in this study is that of Schema Therapy. This seems to take a few forms in the eating disorders. It is based on the idea that early life experiences lead to a series of core beliefs about the self (rather than automatic thoughts) which may in turn maintain eating disorders. There is some evidence for Schema Therapy (using schema modes; Simpson et al. 2010). Therapy aims to increase awareness of early maladaptive schemas and schema modes and the early experience from which they developed and then to modify the schemas in an effort to reduce eating disordered behaviour. Schemas are modified by using imagery and other experiential techniques. A healthier ‘adult self’ is developed in order to bring about a more mature perspective, including more reasoned and rational responses. This approach looks at these ‘underlying’ cognitions rather than a focus on challenging automatic thoughts and assumptions relating to food, weight and shape. (Although to be fair, the more recent incarnations of CBT, such as CBT-E, do not focus on this level of cognitive content either). It is assumed that binge eating serves a function of regulating the strong emotion that arises when schemas are activated, rather than thoughts about food, weight and shape.
In a way this study is trying to look at what might be a core maintaining factor of binge eating. Is it over-evaluation of weight and shape (CBT), dysregulation of response to appetite (CBT-A) or emotional dysregulation (Schema Therapy)? From a clinical perspective, all three may or may not be involved. It is not as though these things are mutually exclusive.
What happened during the study?
You can read the details of the study in the attached link, but I will summarise them. In brief, no differences were found in three groups on the outcome measure of binge frequency or other behavioural or psychological aspects of the eating disorders. At the end of treatment and at 12 month follow up there were large changes in binge eating, indicating that in this study all treatments were effective. That is an example of the Dodo hypothesis where ‘everyone gets a prize’. This always raises the issue of whether any therapy may be helpful, so therapists can do whatever they want and achieve results. I would warn against this. All these therapies are based on a sound theoretical understanding of binge eating, as I have outlined above.
Should we be surprised by a Dodo hypothesis? I am not. In a clinical setting, where I happily work with the patient to develop an individual formulation of what drives their problem, it may be over-evaluation of weight and shape, dysregulation of appetite or emotion regulation. I would agree with the patient and decide where the best place to focus treatment may be.
The study outcomes were in line with previous findings of studies of CBT. Around 50% of the sample was abstinent from binge eating at end of treatment and follow up. That is, half of the sample were not abstinent at the end of treatment, which is of course not to say they were not helped by the treatment. A study which would be more interesting to me as a clinician would be to take the 50% of patients not abstinent at end of treatment and then deliver either CBT-A or Schema Therapy to see if adding an additional treatment at the end of CBT increases outcome.
As always, thoughts and feedback welcome, either in the comments section or on the Facebook link.