Repeated ambulance use is associated with chronic diseases - a population-based historic cohort study of patients' symptoms and diagnoses

Abstract

Background: There is a growing demand for emergency medical services (EMS) and patients are repeatedly transported by ambulance services. For many patients, especially those with chronic disease, there may be better ways of delivering care. We examined the symptom at time of emergency call and the hospital diagnosis for those ambulance users who repeatedly received an ambulance.

Methods: Population-based historic cohort study of patients receiving an ambulance after an emergency call between 2011 and 2014: one-time users (i.e. one ambulance run in any 12 month period) were compared to two-time users (two runs in any 12 month period) and frequent users (>two runs). The presenting symptom according to the Danish Index for Emergency Care from the EMS calls and the hospital ICD-10 discharge diagnoses were obtained from patient records.

Results: We included 52 533 patients (65 932 emergency ambulance runs). Repeated users constituted 16% of the patients (two-time users 11% and frequent users 5%) and one third of all ambulance runs. The symptoms showing the largest increase in frequency with increasing ambulance use were breathing difficulty (N = 3 905-15% were frequent users); seizure (N = 2 437-10% were frequent users), chest pain (N = 7 616-17% were frequent users), and alcohol intoxication (N = 1 998-5% were frequent users). The hospital diagnoses with a corresponding increase were respiratory diseases (N = 4 381) - 13% were frequent users), mental disorders (predominately abuse of alcohol) (N = 3 087-10% were frequent users) and neurological diseases (predominately epilepsy) (N = 2 207-6% were frequent users). 5% of one-time users, 12% of two-time users and 16% of frequent users had a Charlson Comorbidity Index > = 3.

Conclusion: Repeated use of ambulance services was common and associated with chronic health problems such as chronic respiratory diseases, epilepsy, mental disorders with alcohol abuse and comorbidity. Alternative methods of caring for many of these patients should be considered.

Trial registration: None.

Keywords: Ambulance; Denmark; Diagnoses; Emergency call; Emergency medical services; Frequent users; Repeated users.

Fig. 1

Definition of user groups. The three groups of users based on the identified ambulance runs in the study period

Fig. 2

Flowchart of study inclusion process. Flowchart displaying the inclusion of the study population and exclusion criteria

Fig. 3

Distribution of symptoms when calling EMS among user groups. Distribution of symptoms assigned when calling EMS (N = 53 370 runs). ‘Injury’ is a collapsed category covering the three symptoms ‘wounds’, ‘accidents’ and ‘traffic accidents’

Fig. 4

Association between user groups and symptoms. Crude odds ratio plot of the association between selected symptoms when calling EMS and ambulance use. The figure consists of several logistic regressions testing each symptom against all other symptoms. The dots represent the OR and the whiskers are the 95%CIs

Fig. 5

Association between user groups and hospital diagnoses. Odds ratio plot of the association between selected hospital diagnoses and ambulance use. Adjusted for age, gender and comorbidity. The figure consists of several logistic regressions testing each hospital diagnosis against all other diagnoses. The dots represent the OR and the whiskers are the 95%CIs