A cognitive behavioural theory of anorexia nervosa

Denial and resistance to change are prominent features in most patients with anorexia nervosa. The egosyntonic quality of symptoms can contribute to inaccuracy in self-report, avoidance of treatment, difficulties in establishing a therapeutic relationship, and high rates of attrition and relapse. Individuals with bulimia nervosa are typically more motivated to recover, but often ambivalent about forfeiting the ideal of slenderness and the protective functions of binge-purge behavior. Few attempts have been made to assess denial and resistance in the eating disorders, or to examine alternative strategies for enhancing motivation to change. Review of the clinical literature indicates a striking convergence of recommendations across conceptually distinct treatment approaches. Clinicians are encouraged to acquire a frame of reference that can help them understand the private experience of individuals with eating disorders, empathize with their distress at the prospect of weight gain, and acknowledge the difficulty of change. The Socratic method seems particularly well-suited to work with this population because of its emphasis on collaboration, openness, curiosity, patience, focused and systematic inquiry, and individual discovery. Four themes are crucial in engaging reluctant eating-disordered clients in therapy: the provision of psychoeducational material, an examination of the advantages and disadvantages of symptoms, the explicit use of experimental strategies, and an exploration of personal values.

All dominant models of the eating disorders implicate personality variables in the emergence of weight concerns and the development of specific symptoms such as bingeing and purging. Standardized measures of personality traits and disorders generally confirm clinical descriptions of restricting anorexics as constricted, conforming, and obsessional individuals. A less consistent picture suggesting affective instability and impulsivity has emerged from the assessment of subjects with bulimia nervosa. Considerable heterogeneity exists within eating disorder subtypes, however, and a number of special problems complicate the interpretation of personality data in this population. These include young age at onset, the influence of state variables such as depression and starvation sequelae, denial and distortion in self-report, the instability of subtype diagnoses, and the persistence of residual problems following symptom control.

This paper is concerned with the description of an aetiological model of anorexia nervosa and one form of bulimia nervosa. The model has been generated within the conceptual framework of 'functional analysis' and is based on a combination of research evidence and clinical observation. The model attempts to explain the development of anorexia nervosa in terms of a set of hypothesized antecedent events/variables and its maintenance/exacerbation in terms of both positive and negative reinforcers. Specifically it is suggested that initial dieting behaviour is triggered by apparently innocuous psychosocial stimuli, in the context of major setting conditions which predispose the individual towards self- and bodily control: an that successful dieting is then powerfully reinforced by its consequences, which rapidly lead to a downward spiralling into full-blown anorexia nervosa. In this formulation anorexia nervosa is viewed as an attempted adaptive strategy (which has functional value to the individual), given the major setting conditions of the individual's current life situation. Similarly, bulimia nervosa following on from anorexia nervosa is viewed as an attempted adaptive strategy given prevailing environmental and biological pressures towards increasing food intake. The model is presented in the form of diagrammatic formulations and its theoretical and therapeutic implications discussed in relation to the relevant literature..