Profiling Bispebjerg Acute Cohort: Database Formation, Acute Contact Characteristics of a Metropolitan Hospital, and Comparisons to Urban and Rural Hospitals in Denmark

Rasmus Gregersen,1,2 Cathrine Fox Maule,3 Henriette Husum Bak-Jensen,2 Allan Linneberg,3,4 Olav Wendelboe Nielsen,4,5 Simon Francis Thomsen,6 Christian S Meyhoff,2,4,7 Kim Dalhoff,4,8 Michael Krogsgaard,4,9 Henrik Palm,4,9 Hanne Christensen,4,10 Celeste Porsbjerg,4,11 Kristian Antonsen,12 Jørgen Rungby,2,4,13 Steen B Haugaard,2,4,13 Janne Petersen,3,14 Finn E Nielsen1,2 1Department of Emergency Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 2Copenhagen Center for Translational Research, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 3Center for Clinical Research and Prevention, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 4Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark; 5Department of Cardiology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 6Department of Dermatology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 7Department of Anaesthesia and Intensive Care, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 8Department of Clinical Pharmacology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 9Department of Orthopedics, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 10Department of Neurology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 11Department of Respiratory Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 12Executive Board, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 13Department of Endocrinology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 14Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, DenmarkCorrespondence: Rasmus Gregersen, Department of Emergency Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, NV, 2400, Denmark, Email rasmus.gregersen@regionh.dkPurpose: To present a metropolitan cohort, Bispebjerg acute cohort (BAC), and compare patient characteristics and outcomes with patients from urban and rural hospitals in Denmark.Patients and Methods: We linked data from seven Danish nationwide registries and included all acute contacts to non-psychiatric hospitals in the years 2016– 2018. Acute hospital contacts to Bispebjerg and Frederiksberg Hospital constituted BAC, representing a solely metropolitan/urban catchment area. Patient characteristics and outcomes were compared to the rest of Denmark in an urban cohort (UrC) and a rural cohort (RuC), stratified by visit and hospitalization contact types.Results: We identified 4,063,420 acute hospital contacts in Denmark and BAC constituted 8.4% (n=343,200) of them. BAC had a higher proportion of visits (65.1%) compared with UrC (52.1%) and RuC (45.3%). Patients in BAC more often lived alone (visits: BAC: 34.8%, UrC: 30.6%, RuC: 29.2%; hospitalizations: BAC: 50.8%, UrC: 36.7%, RuC: 37.2%) and had temporary CPR number (visits: BAC: 4.4%, UrC: 1.9%, RuC: 1.6%; hospitalizations: BAC: 1.5%, UrC: 0.9%, RuC: 0.8%). Visit patients in BAC were younger (BAC: 36, UrC: 42, RuC: 45 years, median), more often students (BAC: 18.0%, UrC: 14.0%, RuC: 12.5%), and had more contacts due to infectious diseases (BAC: 19.8%, UrC: 14.1%, RuC: 6.2%) but less due to injuries (BAC: 40.0%, UrC: 43.8%, RuC: 60.7%). Hospitalized patients in BAC had higher median age (BAC: 64, UrC: 61, RuC: 64 years) and fewer were in employment than in UrC (BAC: 26.1%, UrC: 32.1%, RuC: 28.1%). BAC Hospitalizations had a lower death rate within 30 days than in RuC (BAC: 3.0% [2.9– 3.1%], UrC: 3.1% [3.0– 3.1%], RuC: 3.4% [3.3– 3.4%]), but a higher readmission-rate (BAC: 20.5% [20.3– 20.8%], UrC: 17.3% [17.2– 17.4%], RuC: 17.5% [17.5– 17.6%]).Conclusion: Significant differences between BAC, urban, and rural cohorts may be explained by differences in healthcare structure and sociodemographics of the catchment areas.Keywords: emergency medicine, acute care, urban-rural disparities, registry-based research, Danish national registers, epidemiology