Psychiatric and somatic morbidity patterns among patients diagnosed with anorexia nervosa and the risk of involuntary treatment: register-based cohort study

Abstract

Background Involuntary treatment for patients with anorexia nervosa is common and lifesaving, but also highly intrusive. Understanding how morbidity patterns relate to involuntary treatment can help minimise its use. Aim We estimate the relative risk of involuntary treatment according to morbidity profiles in patients with anorexia nervosa. Method This register-based cohort study included all individuals diagnosed with anorexia nervosa (ICD-10: F50.0, F50.1) between 1 January 2000 and 31 December 2016 in Denmark. Individuals were grouped by prior morbidities using latent class analysis (LCA). Cox proportional hazards regression estimated the relative risk of first involuntary treatment (e.g. involuntary admission, detention, locked wards) after a diagnosis with anorexia nervosa, regardless of the associated diagnosis. The relative risk of involuntary treatment was estimated with latent classes and the number of morbidities as exposure. Results A total of 9892 individuals with anorexia nervosa were included (93.3% female), of which 821 (8.3%) individuals experienced at least one involuntary treatment event. The LCA produced six classes, with distinct morbidity profiles. The highest hazard ratio was observed for a group characterised by personality disorders, self-harm and substance misuse (hazard ratio 4.46, 95% CI: 3.43–5.79) followed by a high burden group with somatic and psychiatric disorders (hazard ratio 3.96, 95% CI: 2.81–5.59) and a group with developmental and behavioural disorders (hazard ratio 3.61, 95% CI: 2.54–5.11). The relative risk of involuntary treatment increased primarily with the number of psychiatric morbidities. Conclusions Specific morbidity groups are associated with highly elevated risk of involuntary treatment among patients with anorexia nervosa. Targeting preventive interventions to high-risk groups may help reduce the need for involuntary treatment.