Risk of First General Hospital Admissions for Self-Harm Among People With Personality Disorder: A Retrospective Cohort Study

Abstract
For individuals with a personality disorder (PD), it is unknown whether additional psychiatric conditions increase their risk of self-harm. The authors therefore conducted a retrospective cohort study, using data from secondary mental health care, to identify self-harm admissions. Adults with diagnosed PD, followed up over a 6-year period, were involved (N = 7,475). Cox regression was used to model the risk of self-harm admissions, with comorbid depression, substance use disorders (SUD), severe mental illness (SMI), anorexia nervosa (AN), and bulimia nervosa (BN) as primary exposures; sociodemographics were considered as confounders. In multivariable analyses, comorbid SUD (adjusted HR = 1.66; 95% CI [1.45, 1.90]), depressive disorder (1.25; [1.09, 1.44]), AN (1.63; [1.10, 2.39]), and BN (1.65; [1.09, 2.51]) were positively associated with increased risks of hospitalization due to self-harm. However, a negative association was found for comorbid SMI. The findings highlight the importance of assessing and treating comorbid psychiatric disorders in PD.