1. Yilmaz, Z., Hardaway, J. A. & Bulik, C. M. Genetics and Epigenetics of Eating Disorders. Adv. Genomics Genet. 5, 131–150 (2015).
2. Arcelus, J., Mitchell, A. J., Wales, J. & Nielsen, S. Mortality rates in patients with anorexia nervosa and other eating disorders. A meta-analysis of 36 studies. Arch. Gen. Psychiatry 68, 724–731 (2011).
3. Fichter, M. M., Quadflieg, N., Crosby, R. D. & Koch, S. Long‐term outcome of anorexia nervosa: Results from a large clinical longitudinal study. Int. J. Eat. Disord. 50, 1018–1030 (2017).
4. Steinhausen, H.-C. Outcome of eating disorders. Child Adolesc. Psychiatr. Clin. N. Am. 18, 225–242 (2009).
5. Noordenbos, G., Oldenhave, A., Muschter, J. & Terpstra, N. Characteristics and Treatment of Patients with Chronic Eating Disorders. Eat. Disord. 10, 15–29 (2002).
6. Long, C. G., Fitzgerald, K.-A. & Hollin, C. R. Treatment of chronic anorexia nervosa: a 4-year follow-up of adult patients treated in an acute inpatient setting. Clin. Psychol. Psychother. 19, 1–13 (2012).
7. Robinson, P. H. Severe and Enduring Eating Disorder. (John Wiley & Sons, Ltd, 2009).
8. Andries, A., Frystyk, J., Flyvbjerg, A. & Støving, R. K. Dronabinol in severe, enduring anorexia nervosa: a randomized controlled trial. Int. J. Eat. Disord. 47, 18–23 (2014).
9. Fox, J. R. E. & Diab, P. An exploration of the perceptions and experiences of living with chronic anorexia nervosa while an inpatient on an Eating Disorders Unit: An Interpretative Phenomenological Analysis (IPA) study. J. Health Psychol. 20, 27–36 (2013).
10. Dawson, L., Rhodes, P. & Touyz, S. “Doing the Impossible”: The Process of Recovery From Chronic Anorexia Nervosa. Qual. Health Res. 24, 494–505 (2014).
11. Touyz, S. et al. Treating severe and enduring anorexia nervosa: a randomized controlled trial. Psychol. Med. 43, 2501–2511 (2013).
12. Arkell, J. & Robinson, P. A pilot case series using qualitative and quantitative methods: biological, psychological and social outcome in severe and enduring eating disorder (anorexia nervosa). Int. J. Eat. Disord. 41, 650–656 (2008).
13. Keski-Rahkonen, A. et al. Factors associated with recovery from anorexia nervosa: A population-based study. Int. J. Eat. Disord. 47, 117–123 (2014).
14. Zipfel, S., Lowe, B., Reas, D. L., Deter, H. C. & Herzog, W. Long-term prognosis in anorexia nervosa: lessons from a 21-year follow-up study. Lancet (London, England) vol. 355 721–722 (2000).
15. Löwe, B. et al. Long-term outcome of anorexia nervosa in a prospective 21-year follow-up study. Psychol. Med. 31, 881–890 (2001).
16. Lock, J. et al. Do end of treatment assessments predict outcome at follow-up in eating disorders? Int. J. Eat. Disord. 46, 771–778 (2013).
17. Keel, P. K., Mitchell, J. E., Miller, K. B., Davis, T. L. & Crow, S. J. Long-term Outcome of Bulimia Nervosa. Arch. Gen. Psychiatry 56, 63–69 (1999).
18. Keel, P. K. & Brown, T. A. Update on course and outcome in eating disorders. Int. J. Eat. Disord. 43, 195–204 (2010).
19. Bulik, C. M., Sullivan, P. F., Joyce, P. R., Carter, F. A. & McIntosh, V. V. Predictors of 1-year treatment outcome in bulimia nervosa. Compr. Psychiatry 39, 206–214 (1998).
20. Robinson, P. Severe and enduring eating disorders: recognition and management. Adv. Psychiatr. Treat. 20, 392–401 (2014).
21. Berkman, N. D., Lohr, K. N. & Bulik, C. M. Outcomes of eating disorders: a systematic review of the literature. Int. J. Eat. Disord. 40, 293–309 (2007).
22. Steinhausen, H.-C. The outcome of anorexia nervosa in the 20th century. Am. J. Psychiatry 159, 1284–1293 (2002).
23. Zhang, R. et al. Familial co-aggregation of schizophrenia and eating disorders in Sweden and Denmark. Mol. Psychiatry (2020) doi:10.1038/s41380-020-0749-x.
24. Foulon, C. [Schizophrenia and eating disorders]. Encephale. 29, 463–466 (2003).
25. Khalil, R. B., Hachem, D. & Richa, S. Eating disorders and schizophrenia in male patients: A review. Eat. Weight Disord. - Stud. Anorexia, Bulim. Obes. 16, e150–e156 (2011).
26. Götestam, K. G., Eriksen, L. & Hagen, H. An epidemiological study of eating disorders in Norwegian psychiatric institutions. Int. J. Eat. Disord. 18, 263–268 (1995).
27. Watson, H. J. et al. Genome-wide association study identifies eight risk loci and implicates metabo-psychiatric origins for anorexia nervosa. Nat. Genet. 51, 1207–1214 (2019).
28. Maier, R. M., Visscher, P. M., Robinson, M. R. & Wray, N. R. Embracing polygenicity: A review of methods and tools for psychiatric genetics research. Psychol. Med. 48, 1055–1067 (2018).
29. Howard, D. M. et al. Genome-wide meta-analysis of depression identifies 102 independent variants and highlights the importance of the prefrontal brain regions. Nat. Neurosci. 22, 343–352 (2019).
30. Stahl, E. A. et al. Genome-wide association study identifies 30 loci associated with bipolar disorder. Nat. Genet. 51, 793–803 (2019).
31. Ripke, S. et al. Biological insights from 108 schizophrenia-associated genetic loci. Nature 511, 421–427 (2014).
32. Bulik-Sullivan, B. et al. An atlas of genetic correlations across human diseases and traits. Nat. Genet. 47, 1236–1241 (2015).
33. Smoller, J. W. et al. Psychiatric genetics and the structure of psychopathology. Mol. Psychiatry 24, 409–420 (2019).
34. Bauer, A. E. et al. Genetic risk scores for major psychiatric disorders and the risk of postpartum psychiatric disorders. Transl. Psychiatry 9, 288 (2019).
35. Bohn, K. et al. The measurement of impairment due to eating disorder psychopathology. Behav. Res. Ther. 46, 1105–1110 (2008).
36. Mayer, L. E. S. et al. Does percent body fat predict outcome in anorexia nervosa? Am. J. Psychiatry 164, 970–972 (2007).
37. Bodell, L. P. & Mayer, L. E. S. Percent body fat is a risk factor for relapse in anorexia nervosa: a replication study. Int. J. Eat. Disord. 44, 118–123 (2011).
38. El Ghoch, M., Calugi, S., Chignola, E., Bazzani, P. V & Dalle Grave, R. Body mass index, body fat and risk factor of relapse in anorexia nervosa. Eur. J. Clin. Nutr. 70, 194–198 (2016).
39. Thornton, L. M. et al. The Anorexia Nervosa Genetics Initiative (ANGI): Overview and methods. Contemp. Clin. Trials 74, 61–69 (2018).
40. Birgegard, A., Bjorck, C. & Clinton, D. Quality assurance of specialised treatment of eating disorders using large-scale Internet-based collection systems: methods, results and lessons learned from designing the Stepwise database. Eur. Eat. Disord. Rev. 18, 251–259 (2010).
41. Schaumberg, K. et al. Patterns of diagnostic transition in eating disorders: a longitudinal population study in Sweden. Psychol. Med. 49, 819–827 (2019).
42. Birgegård, A. & De Man Lapidoth, J. Validation of the structured eating disorder interview (SEDI) against the eating disorder examination (EDE). Karolinska Institutet (2010).
43. First, M. B., Gibbon, M., Spitzer, R. L., & Williams, J. B. W. Structured clinical interview for DSM-IV Axis I disorders (J. Herlofson Trans.). Danderyd: Pilgrim Press. ((J. Herlofson Trans.). Danderyd: Pilgrim Press., 1998).
44. Kearney, C. A., Freeman, A. & Bacon, V. 11 - Structured and semistructured interviews for children. in (eds. Goldstein, G., Allen, D. N. & DeLuca, J. B. T.-H. of P. A. (Fourth E.) 337–353 (Academic Press, 2019). doi:https://doi.org/10.1016/B978-0-12-802203-0.00011-0.
45. Holgado–Tello, F. P., Chacón–Moscoso, S., Barbero–García, I. & Vila–Abad, E. Polychoric versus Pearson correlations in exploratory and confirmatory factor analysis of ordinal variables. Qual. Quant. 44, 153 (2008).
46. Ekeroth, K. & Birgegård, A. Author ’ s personal copy Evaluating reliable and clinically signi fi cant change in eating disorders : Comparisons to changes in DSM-IV diagnoses.
47. Yengo, L. et al. Meta-analysis of genome-wide association studies for height and body mass index in ∼700000 individuals of European ancestry. Hum. Mol. Genet. 27, 3641–3649 (2018).
48. Choi, S. W. & O’Reilly, P. F. PRSice-2: Polygenic Risk Score software for biobank-scale data. Gigascience 8, (2019).
49. Ackard, D. M., Richter, S., Egan, A. & Cronemeyer, C. Poor outcome and death among youth, young adults, and midlife adults with eating disorders: an investigation of risk factors by age at assessment. Int. J. Eat. Disord. 47, 825–835 (2014).
50. Kinasz, K., Accurso, E. C., Kass, A. E. & Le Grange, D. Does Sex Matter in the Clinical Presentation of Eating Disorders in Youth? J. Adolesc. Health 58, 410–416 (2016).
51. Striegel-Moore, R. H. et al. Gender difference in the prevalence of eating disorder symptoms. Int. J. Eat. Disord. 42, 471–474 (2009).
52. Klump, K. L., Keel, P. K., Sisk, C. & Burt, S. A. Preliminary evidence that estradiol moderates genetic influences on disordered eating attitudes and behaviors during puberty. Psychol. Med. 40, 1745–1753 (2010).
53. Price, A. L. et al. Principal components analysis corrects for stratification in genome-wide association studies. Nat. Genet. 38, 904–909 (2006).
54. Purcell, S. et al. PLINK: a tool set for whole-genome association and population-based linkage analyses. Am. J. Hum. Genet. 81, 559–575 (2007).
55. Wray, N. R. et al. Research review: Polygenic methods and their application to psychiatric traits. J. Child Psychol. Psychiatry. 55, 1068–1087 (2014).
56. Murray, G. K. et al. Could Polygenic Risk Scores Be Useful in Psychiatry?: A Review. JAMA psychiatry (2020) doi:10.1001/jamapsychiatry.2020.3042.
57. Levine, M. E. et al. A polygenic risk score associated with measures of depressive symptoms among older adults. Biodemography Soc. Biol. 60, 199–211 (2014).
58. Zhang, J.-P. et al. Schizophrenia Polygenic Risk Score as a Predictor of Antipsychotic Efficacy in First-Episode Psychosis. Am. J. Psychiatry 176, 21–28 (2019).
59. Hübel, C. et al. Binge-eating disorder, anorexia nervosa, and constitutional thinness differ in their associations with anthropometric and psychiatric polygenic scores. medRxiv 2020.03.24.20042648 (2020) doi:10.1101/2020.03.24.20042648.
60. Vandereycken, W. Denial of illness in anorexia nervosa—a conceptual review: part 1 diagnostic significance and assessment. Eur. Eat. Disord. Rev. 14, 341–351 (2006).
61. Vandereycken, W. Denial of illness in anorexia nervosa—a conceptual review: part 2 different forms and meanings. Eur. Eat. Disord. Rev. 14, 352–368 (2006).
62. Duncan, L. et al. Significant Locus and Metabolic Genetic Correlations Revealed in Genome-Wide Association Study of Anorexia Nervosa. Am. J. Psychiatry 174, 850–858 (2017).
63. Nagata, J. M. et al. Genetic risk, body mass index, and weight control behaviors: Unlocking the triad. Int. J. Eat. Disord. 52, 825–833 (2019).
64. Abdulkadir, M. et al. Polygenic Score for Body Mass Index Is Associated with Disordered Eating in a General Population Cohort. J. Clin. Med. 9, 1187 (2020).
65. Ursini, G. et al. Convergence of placenta biology and genetic risk for schizophrenia. Nat. Med. 24, 792–801 (2018).
66. Vassos, E. et al. Lack of Support for the Genes by Early Environment Interaction Hypothesis in the Pathogenesis of Schizophrenia. Schizophr. Bull. (2021) doi:10.1093/schbul/sbab052.
67. Kim, Y., Zerwas, S., Trace, S. E. & Sullivan, P. F. Schizophrenia genetics: where next? Schizophr. Bull. 37, 456–463 (2011).
68. Lewis, C. M. & Vassos, E. Prospects for using risk scores in polygenic medicine. Genome Med. 9, 96 (2017).
69. Wonderlich, S. A., Bulik, C. M., Schmidt, U., Steiger, H. & Hoek, H. W. Severe and enduring anorexia nervosa: Update and observations about the current clinical reality. Int. J. Eat. Disord. 53, 1303–1312 (2020).
70. Kaye, W. H. & Bulik, C. M. A crisis in care: The treatment of anorexia nervosa in the US. JAMA Psychiatry.