BackgroundPsychological distress in medical patients admitted to the emergency department (ED) is not well studied. Our aim was to investigate the extent of psychological distress in a broad and unselected medical patient sample 30 days after ED admission and its association with socio-demographic and clinical variables.MethodWe used data from a prospective observational cohort study including 1575 consecutive adult medical patients presenting to the ED with acute somatic conditions. Outcome variables were patient’s psychological distress measured by the 4-item Patient Health Questionnaire (PHQ–4) and self-rated health assessed 30 days after ED admission using telephone interviews. Risk factors included socio-demographic variables (e.g. gender, marital status), clinical presentation (e.g. illness severity, main initial diagnosis) and course of illness (e.g. rehospitalisation, length of hospital stay).ResultsA total of 38 % of patients had evidence for psychological distress 30 days after ED admission. Multivariate analysis found female gender (adjusted odds ratio [aOR] 1.35, 95 % confidence interval [CI] 1.02 to 1.78), comorbid psychiatric disorder (aOR 1.63, 95 % CI 1.08 to 2.62), discharge to a post-acute care institution (aOR 1.47, 95 % CI 1.03 to 2.09), unplanned rehospitalisation (aOR 2.38, 95 % CI 1.47 to 3.86), and unplanned visit at general practitioner (aOR 4.75, 95 % CI 2.57 to 8.80) to be associated with distress at day 30 following ED admission.ConclusionsOne month after ED admission a significant number of patients still show a moderate amount of psychophysical distress. Strongest related variables were course of illness, in particular unplanned general practitioner visits. Future interventional studies should assess possibilities to reduce distress in patients at increased risk.Trial registrationNCT01768494, January 9, 2013 (registration date), February 25, 2013 (enrolment of first participant).