Original ContributionSyncope prevalence in the ED compared to general practice and population: a strong selection process☆
Introduction
Transient loss of consciousness (TLOC) is a symptom of both benign and potentially lethal clinical disorders. It can be caused by syncope, neurological syndromes, and psychiatric or metabolic disorders. What all these disorders have in common is that patients lose consciousness, but presentation is usually quite different. Syncope is defined as TLOC caused by a fall in systemic blood pressure resulting in a reduction in blood flow to the brain. Important causes of syncope are neurally mediated reflex-syncopal syndromes and cardiac disorders [1], [2].
For a cost-effective diagnostic approach of patients with TLOC and to permit design of clinical trials, diagnostic strategies, and health services delivery, knowledge of the epidemiology of the various causes of TLOC in different clinical settings is required [3], [4], [5]. However, the body of knowledge regarding the epidemiology of TLOC is far from complete.
Recent studies have shown that the lifetime cumulative incidence of syncope in the general population in subjects up to 65 years of age is between 35% and 39% [6], [7], [8], [9], [10], [11]. About 80% of these subjects have their first episode before the age of 30 years, and most subjects with syncope are women. Only a subgroup presents to a medical doctor. In the Framingham offspring study, 44% of the participants (mean age = 51 years, range = 20-96 years) with an episode of TLOC reported that they did not seek medical advice [12]. In a younger group, this percentage may even be higher because syncopal episodes in young subjects are generally considered to be innocent [4]. Whether this difference in referral pattern between young and elderly subjects indeed exists has not been studied.
In The Netherlands, the prevalence of the complaint fainting in the general practice is estimated at 2 to 9 per 1000 encounters, with a peak of predominantly females in the age group between 10 and 30 years and a peak above the age of 65 years in both men and women [4], [13]. In comparison, the number of patients presenting to their general practitioner (GP) with epilepsy is about 10 times lower (0.2-0.8 per 1000 patient years) [13], [14], [15], and also, cardiac syncope is very rare [13].
Although we know that history and physical examination are important tools to risk stratify patients with TLOC [16], [17], the demographical characteristics and clinical features of patients with TLOC presenting to the emergency department (ED), either directly or referred by their GP, have not been studied in detail. This study therefore focuses on the epidemiology of TLOC in the emergency setting.
The first aim of this study is to assess the prevalence of TLOC in the ED and chest pain unit (CPU) of a university hospital in The Netherlands and to determine the frequency distribution of the different causes of the TLOC in patients presenting to the ED and CPU. The second aim is to gain insight into the selection and referral process of patients with syncope, in particular the proportion from the general population that presents to a GP and/or ED/CPU. We hypothesize that only a small proportion of the patients with syncope visit EDs, but their syncopal etiology is more often dangerous.
Section snippets
Study population
This retrospective chart review was conducted in the ED and CPU of the Academic Medical Centre in Amsterdam, The Netherlands. The study was performed with the use of the routine charts of consecutive TLOC patients in the ED and CPU. All patients presenting with an episode of TLOC to the ED or CPU between January 1, 2000, and January 1, 2002, were included. Patients with a known epileptic disorder and patients younger than 12 years were excluded. From patients who visited the ED or CPU more than
Characteristics of study subjects
From January 1, 2000, until January 1, 2002, 65 726 patients visited the ED and 5583 patients visited the CPU. Of these patients, 672 (0.94%) of 71 309 presented with TLOC, 526 (0.80%) at the ED and 146 (2.6%) at the CPU. Twenty-three patients (3.4%) were referred from the ED to the CPU. They were analyzed in the ED group. Two patients visited the ED more than once.
The characteristics of the patients with TLOC are displayed in Table 1. In the ED, 46% of the patients was men vs 60% in the CPU (P
Main findings
In this study, 0.94% of the patients visiting the ED (0.80%) and CPU (2.6%) presented with TLOC. Half of the patients presenting with TLOC are diagnosed with syncope. Both in the ED (45%) and CPU (21%), reflex syncope is the main cause. Cardiac syncope is 10 times more prevalent in the CPU than in the ED (18% in the CPU vs 1.7% in the ED; P < .01). The event rate for syncope in the general population is much higher than the presentation rate in general practice, which exceeds the presentation
References (36)
- et al.
Prevalence and triggers of syncope in medical students
Am J Cardiol
(2003) - et al.
Clinical policy: critical issues in the evaluation and management of adult patients presenting to the emergency department with syncope
Ann Emerg Med
(2007) - et al.
Prospective evaluation of patients with syncope: a population-based study
Am J Med
(2001) - et al.
Evaluation and outcome of emergency room patients with transient loss of consciousness
Am J Med
(1982) - et al.
Prevalence of orthostatic hypotension among patients presenting with syncope in the ED
Am J Emerg Med
(2002) - et al.
Syncope in children and adolescents
J Am Coll Cardiol
(1997) Syncope
N Engl J Med
(2000)- et al.
Defining and classifying syncope
Clin Auton Res
(2004) - et al.
Epidemiologic aspects of transient loss of consciousness/syncope
- et al.
Epidemiology of reflex syncope
Clin Auton Res
(2004)
Syncope—past, present and future
Clin Auton Res
Lifetime cumulative incidence of syncope in the general population: a study of 549 Dutch subjects aged 35-60 years
J Cardiovasc Electrophysiol
Syncope in migraine. The population-based CAMERA study
Neurology
Age of first faint in patients with vasovagal syncope
J Cardiovasc Electrophysiol
Vasovagal syncope in medical students and their first-degree relatives
Eur Heart J
Prevalence of syncope in a population aged more than 45 years
Am J Med
Incidence and prognosis of syncope
N Engl J Med
Initial diagnostic strategy in the case of transient losses of consciousness: the importance of the medical history
Ned Tijdschr Geneeskd
Cited by (123)
Can I Send This Syncope Patient Home From the Emergency Department?
2021, Journal of Emergency MedicineThe association between the biometeorological indicators and emergency interventions due to fainting: A retrospective cohort study
2021, Science of the Total Environment
- ☆
This paper was sponsored by an unrestricted educational grant from Medtronic Inc.