title: Anorexia nervosa.
abstract: Anorexia nervosa (AN) is a psychiatric condition characterized by severe weight loss and secondary problems associated with malnutrition. AN predominantly develops in adolescence in the peripubertal period. Without early effective treatment, the course is protracted with physical, psychological and social morbidity and high mortality. Despite these effects, patients are noted to value the beliefs and behaviours that contribute to their illness rather than regarding them as problematic, which interferes with screening, prevention and early intervention. Involving the family to support interventions early in the course of the illness can produce sustained changes; however, those with a severe and/or protracted illness might require inpatient nursing support and/or outpatient psychotherapy. Prevention programmes aim to moderate the overvaluation of 'thinness' and body dissatisfaction as one of the proximal risk factors. The low prevalence of AN limits the ability to identify risk factors and to study the timing and sex distribution of the condition. However, genetic profiles, premorbid features, and brain structures and functions of patients with AN show similarities with other psychiatric disorders and contrast with obesity and metabolic disorders. Such studies are informing approaches to address the neuroadaptation to starvation and the other various physical and psychosocial deficits associated with AN. This Primer describes the epidemiology, diagnosis, screening and prevention, aetiology, treatment and quality of life of patients with AN.
authors.affiliation: King's College London, Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), London SE5 8AF, UK.
authors.forename: Janet
authors.initials: J
authors.lastname: Treasure
authors.affiliation: Department of Psychosomatic Medicine, University of Tuebingen, Tuebingen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Zipfel
authors.affiliation: University College London, Institute of Child Health, Behavioural and Brain Sciences Unit, London, UK.|Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
authors.forename: Nadia
authors.initials: N
authors.lastname: Micali
authors.affiliation: School of Psychology, Flinders University, Adelaide, Australia.
authors.forename: Tracey
authors.initials: T
authors.lastname: Wade
authors.affiliation: Oregon Research Institute, Eugene, Oregon, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Stice
authors.affiliation: Department of Psychiatry, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Angélica
authors.initials: A
authors.lastname: Claudino
authors.affiliation: King's College London, Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), London SE5 8AF, UK.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schmidt
authors.affiliation: Eating Disorder Centre of Denver, University of Colorado, Denver, Colorado, USA.
authors.forename: Guido K
authors.initials: GK
authors.lastname: Frank
authors.affiliation: University of North Carolina at Chapel Hill, North Carolina, USA.|Karolinska Institutet, Stockholm, Sweden.
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Bulik
authors.affiliation: Gillberg Neuropsychiatry Centre, University of Gothenburg, Gothenburg Sweden.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Wentz
mesh_terms: D000222:Adaptation, Physiological; D000293:Adolescent; D000856:Anorexia Nervosa / Q000503:physiopathology / Q000523:psychology / Q000628:therapy; D001828:Body Image; D006801:Humans; D044342:Malnutrition / Q000503:physiopathology / Q000523:psychology