Background. Given our poor understanding of the very long-term course of anorexia nervosa, many questions remain regarding the potential for recovery and relapse. The purpose of the present study was to investigate long-term outcome and prognosis in an anorexic sample 21 years after the initial treatment.

Method. A multidimensional and prospective design was used to assess outcome in 84 patients 9 years after a previous follow-up and 21 years after admission. Among the 70 living patients, the follow-up rate was 90%. Causes of death for the deceased patients were obtained through the attending physician. Predictors of a poor outcome at the 21-year follow-up were selected based on the results of a previous 12-year follow-up of these patients.

Results. Fifty-one per cent of the patients were found to be fully recovered at follow-up, 21% were partially recovered and 10% still met full diagnostic criteria for anorexia nervosa. Sixteen per cent were deceased, due to causes related to anorexia nervosa. The standardized mortality rate was 9·8. The three groups also showed significant differences in psychosocial outcome. A low body mass index and a greater severity of social and psychological problems were identified as predictors of a poor outcome.

Conclusions. Recovery is still possible for anorexic patients after a period of 21 years. On the other hand, patients can relapse, becoming symptomatic again despite previously achieving recovery status. Only a few patients classified as having a poor outcome were found to seek any form of treatment, therefore, it is recommended that these patients should be monitored regularly and offered treatment whenever possible.