International Validation of Syncope Risk Assessment Score
Dr. Fritz
Clinical question: Does the Canadian Syncope Risk Score (CSRS) compare favorably to another scoring system, Osservatorio Epidemiologico della Sincope nel Lazio (OESIL) in predicting 30-day event outcomes in patients presenting to the emergency department (ED) with syncope?
Background: Risk stratifying syncope patients is fraught with challenges of clinical, social, financial, and legal implications. In the U.S., these factors lead to 80% of patients with syncope being admitted for evaluation with an annual cost of $2.4 billion. There is a need for widespread adoption of a risk scoring system in clinical practice to better assess the need for admission.
Study design: Prospective cohort study
Setting: EDs at 14 hospitals across eight countries (United States, Switzerland, Spain, Germany, Italy, Poland, New Zealand, and Australia)
Synopsis: 2,283 patients who presented to the ED within 12 hours of a syncopal event were included. Patients underwent standardized clinical assessment and clinicians provided a clinical classification (vasovagal, cardiogenic, etc.) of syncope prior to disposition (admission or discharge). Patients were followed at 30 days, and at 6, 12, and 24 months. Analysis was performed on patients according to their disposition status for the primary outcome of serious events (death, myocardial infarction, serious arrhythmia, etc.) occurring that were not evident in the ED. All patients were scored with CSRS and OESIL, and CSRS outperformed OESIL (area under the receiver-operating characteristic curve, 0.85 (95% CI, 0.83 to 0.88) versus 0.74 (CI, 0.71 to 0.78) and 0.80 (CI, 0.75 to 0.84) versus 0.69 (CI, 0.64 to 0.75), respectively). It was found that among patients deemed (very) low risk by CSRS, 0.6% (9/1388) had an event by 30 days, while of those with a moderate or (very) high risk by CSRS, 6.8% (61/895) had an event by 30 days. Limitations included that clinician clinical classification performed similarly to CSRS, but there was no control for provider experience.
Bottom line: The CSRS can help clarify the risk of 30-day significant events in patients presenting with syncope, thus supporting decision making regarding admission.
Citation: Zimmermann T, et al. International validation of the Canadian Syncope Risk Score: A cohort study. Ann Intern Med. 2022;175(6):783-794. doi:10.7326/M21-2313.
Dr. Fritz is an assistant professor of medicine and section chief of hospital medicine at Saint Louis University School of Medicine, St. Louis, Mo.