Mental capacity to consent to treatment and the association with outcome: A longitudinal study in patients with anorexia nervosa

Background Relevance of diminished mental capacity in anorexia nervosa (AN) to course of disorder is unknown. Aims To examine prognostic relevance of diminished mental capacity in AN. Method A longitudinal study was conducted in 70 adult female patients with severe AN. At baseline, mental capacity was assessed by psychiatrists, and clinical and neuropsychological data (decision-making) were collected. After 1 and 2 years, clinical and neuropsychological assessments were repeated, and remission and admission rates were calculated. Results People with AN with diminished mental capacity had a less favourable outcome with regard to remission and were admitted more frequently. Their appreciation of illness remained hampered. Decision-making did not improve, in contrast to people with full mental capacity. Conclusions People with AN with diminished mental capacity seem to do less well in treatment and display decision-making deficiencies that do not ameliorate with weight improvement.