Highlights
- A large-scale prospective study (Sacco et al., 2026) reveals that men presenting with syncope are admitted more frequently (50.4% vs 39.6%) and experience higher 30-day serious adverse events (7.3% vs 4.6%) than women.
- Observed disparities in outcomes and hospitalizations between sexes are statistically neutralized after adjusting for baseline clinical comorbidities, particularly coronary artery disease and heart failure.
- Women consistently undergo less diagnostic testing across most domains (neurologic, cardiac, blood) but are significantly more likely to receive guideline-consistent screening for pulmonary embolism.
- The integration of Point-of-Care Ultrasound (POCUS) significantly improves risk stratification accuracy in the emergency department, potentially reducing diagnostic errors by 4.5 cases per 100 patients.
Background
Syncope and presyncope account for approximately 1% to 3% of all emergency department (ED) visits and up to 6% of hospital admissions in the United States. Despite its prevalence, the clinical management of syncope remains complex due to the broad differential diagnosis, ranging from benign vasovagal episodes to life-threatening cardiac arrhythmias or pulmonary embolisms. Historically, evidence has suggested that clinical pathways and resource utilization may diverge based on patient sex. Understanding whether these differences stem from biological variations in disease prevalence or from systemic biases in risk perception is critical for optimizing evidence-based healthcare and resource allocation.
Key Content
The Sacco Cohort: Baseline Risks and Physician Perception
A pivotal prospective, observational cohort study involving 1,263 patients (53.5% women) across six U.S. emergency departments (Sacco et al., 2026) investigated the intersection of patient sex, physician risk estimation, and clinical outcomes. The study identified that men were significantly more likely to present with baseline cardiac disease, including coronary artery disease (27.8% vs 11.8%) and heart failure (15.3% vs 8.0%).
Physician risk estimation reflected these baseline differences, with a mean estimated 30-day risk of serious adverse events (SAEs) of 7.2% for men compared to 6.1% for women. Correspondingly, men were more frequently admitted to the hospital (50.4% vs 39.6%; Risk Difference [RD]: 11%). Crucially, the higher rate of SAEs in men (7.3% vs 4.6%) was fully explained by these baseline clinical factors; after multivariable adjustment, the association between sex and outcomes was no longer statistically significant. This suggests that ED physicians are generally successful in identifying high-risk clinical markers, regardless of patient sex.
Trends in Resource Utilization and Diagnostic Testing
While the Sacco study focuses on 30-day outcomes, broader longitudinal data (2006–2019) reveal shifting trends in syncope management. The incidence of syncope-related ED visits rose from 9 to 13 per 1,000 patients during this period. Research indicates that women have a significantly lower incidence of testing in most domains, including neurologic and cardiac testing. However, this trend is reversed in the context of pulmonary embolism (PE) screening.
Retrospective data show that women aged 18–49 are more likely than men to receive D-dimer testing (OR 1.30) but are less likely to be diagnosed with PE (OR 0.57). Interestingly, women were found to be more likely to receive care consistent with current guidelines (70% vs 63%), suggesting that the higher volume of testing in females may be a result of closer adherence to diagnostic algorithms rather than over-testing bias.
Diagnostic Yields of Head CT and EEG
In the evaluation of syncope, low-yield testing remains a driver of healthcare costs. A cross-sectional study on head computed tomography (CT) in syncope patients found a new finding rate of 11.4%. While the incidence was higher in elderly males (12.8% vs 9.7% in women), the difference was not statistically significant (P=0.353). Experts conclude that routine head CT is unjustifiable unless specific neurological indicators are present. Similarly, urgent electroencephalograms (EEG) in pediatric emergencies have shown zero abnormalities in cases of suspected syncope, emphasizing the need for more targeted diagnostic approaches.
Methodological Advances: The Role of POCUS
Recent evidence supports the integration of Point-of-Care Ultrasound (POCUS) as a superior risk-stratification tool compared to standard clinical assessment. A prospective cohort study demonstrated that a POCUS-integrated approach yielded a positive likelihood ratio of 5.93 for predicting short-term serious outcomes, compared to only 1.73 for clinical evaluation alone. In adolescent populations, however, sex discrepancies persist, with females being significantly less likely to receive cardiac POCUS for chest pain or syncope (P<0.0001), potentially due to provider discomfort with breast tissue obstruction.
Expert Commentary
The synthesis of recent literature suggests that while sex differences in syncope outcomes exist, they are primarily symptomatic of underlying comorbidity profiles. The findings from the Sacco et al. study are reassuring, as they indicate that the higher admission rates for men are a rational response to higher baseline cardiovascular risks. However, the ‘testing gap’ observed in other studies—where women receive fewer cardiac and neurologic tests—requires careful scrutiny.
It is possible that the lower testing rates in women reflect a higher prevalence of vasovagal or orthostatic syncope, which require less intensive investigation. Conversely, the increased D-dimer testing for PE in women suggests that clinicians may be more vigilant about venous thromboembolism in female patients, perhaps due to the known risks associated with hormonal contraceptives. The clinical challenge remains the reduction of ‘low-value’ care (such as routine head CTs) while ensuring that diagnostic tools like POCUS are applied equitably across sexes to improve risk stratification.
Conclusion
Sex differences in syncope management in the ED are prominent but appear to be clinically grounded in the disparate baseline risk profiles of men and women. While men face higher rates of admission and SAEs, these are mediated by pre-existing cardiac conditions. Progress has been made in establishing that gender-consistent care is being delivered in several domains, particularly in PE screening. Future research should focus on implementing POCUS more broadly and equitably to refine risk estimation and further mitigate unnecessary hospitalizations and costs. Clinicians should continue to rely on validated risk-stratification tools rather than sex as an independent risk factor for adverse syncope outcomes.
References
- Sacco DL, et al. Sex Differences in Clinical Outcomes and Resource Utilization Among Emergency Department Patients With Unexplained Syncope or Presyncope: A Prospective, Observational, Cohort Study. Ann Emerg Med. 2026. PMID: 41860508.
- Suh EH, et al. Trends in syncope testing and admissions in the USA from 2006 through 2019. Clin Auton Res. 2025. PMID: 39560861.
- Probst MA, et al. Sex differences in guideline-consistent diagnostic testing for acute pulmonary embolism among adult emergency department patients. Acad Emerg Med. 2023. PMID: 36911917.
- Bassanini G, et al. Comparison between standard and ultrasound-integrated approach for risk stratification of syncope in the emergency department. Intern Emerg Med. 2022. PMID: 35064436.
