A multisite comparison using electronic health records and natural language processing to identify the association between suicidality and hospital readmission amongst patients with eating disorders

Objective: To describe and compare the association between suicidality and subsequent readmission for patients hospitalised for eating disorder treatment, within two years of discharge, at two large academic medical centres in two different countries.Method: Over an 8-year study window from January 2009 to March 2017, we identified all inpatient eating disorder admissions at Weill Cornell Medicine, New York, USA (WCM) and South London and Maudsley Foundation NHS Trust, London, UK (SLaM). To establish each patient’s - suicidality profile, we applied two Natural Language Processing algorithms (NLP), independently developed at the two institutions, and detected suicidality in clinical notes documented in the first week of admission. We calculated the odds ratios for any subsequent readmission within 2 years post discharge and determined whether this was to another eating disorder unit, other psychiatric unit, a general medical hospital admission or emergency room attendance.Results: We identified 1,126 and 420 eating disorder inpatient admissions at WCM and SLaM, respectively. In the WCM cohort, evidence of above average suicidality during the first week of admission was significantly associated with an increased risk of non-eating disorder related psychiatric readmission (OR 3.48 95%CI=2.03-5.99, p valueDiscussion: Patterns of increased risk of psychiatric readmission from above average suicidality detected via NLP during inpatient eating disorder admissions differed in our two patient cohorts. However, comorbid diagnoses such as personality disorder increased the risk of any psychiatric readmission across both cohorts.