Given the limited understanding of the precise aetiology of eating disorders and the fact that there is no ultimate cure for these disorders, studies in the long-term development of the affected patients are of considerable interest. Along with the amazing increase in scientific studies of various facets of the eating disorders in the second half of the twentieth century, there have also been a notable number of outcome studies. In this chapter, separately for AN and BN, a review will be provided of the various studies on the outcome and prognosis of eating disorders.

Anorexia nervosa

Recently, the author has provided an exhaustive review of the outcome of AN in the twentieth century (Steinhausen, 2002). In this review, a total of 119 study series covering 5590 patients that were published in the English and German literature were analysed with regard to mortality, global outcome and other psychiatric disorders at follow-up.

The four major outcome parameters of mortality, recovery, improvement and chronicity and the other psychiatric disorders were analysed. Descriptive means and standard deviations were calculated as shown in Table 22.1. Given the rather wide standard deviations with extreme ranges across the studies and the varying sizes of the patient groups, the means in this table reflect only a central trend.

The mean crude mortality rate was 5.0%. In the surviving patients, on average, full recovery was found in only less than half (47%) of the patients, while a third improved and 20% developed a chronic course of the disorder.