Anorexia nervosa

Characteristics of the disorder

The diagnostic guidelines for anorexia nervosa in ICD-10 (WHO, 1992) include the following features: marked weight loss to at least 15% below expected weight or a Quetelet's Body Mass Index (BMI) of 17.5 (BMI=body weight in kg/[height in m]2). The weight loss is self-induced predominantly by avoiding highly caloric food. Additional symptoms include: self-induced vomiting, selfinduced purging, excessive physical exercise and the use of appetite depressants and/or diuretics (Brownell and Fairburn, 1995).

The patient has a distortion of body image with the persistent, intrusive and overvalued idea of being ‘too fat’ or being ‘flabby’. Endocrine abnormalities involving the hypothalamic–pituitary–gonadal axis are also present. If the disorder begins prepubertally, development during this period, including growth, is disturbed (Szmukler et al., 1995).

Progressive cachexia is associated with a number of physical changes, which are described in Table 21.1.

Extreme cachexia is associated with neuropsychological disturbances, including poor concentration, mental fatigue and repetitive and obsessional thoughts, which usually concern food and eating. Cranial computed tomography has demonstrated that pseudoatrophy of the brain may occur at this stage, with enlargement of the sulci and the longitudinal cerebral fissure, and in a few cases, even enlargement of the ventricles. Psychological tests usually reveal disturbed concentration, and prolonged reaction times, reduced ability to perceive visual figures, deficient visual–motor coordination and reduced visual memory. These deficits are relevant in psychotherapy, demonstrating the importance of not making excessive cognitive or emotional demands on patients at the beginning of therapy (Remschmidt and Herpertz-Dahlmann, 1988a).