Sex Differences in Patients Hospitalized for Syncope: Experience in University Hospital of Middle-income Country and with a Predominance of Chagasic Etiology

Background: Syncope is a common sign with an inpatient rate of up to 83%. Data on sex differences of patients with syncope in the emergency and hospitalization are scarce.

Aim: The present study aimed to verify sex differences regarding clinical profile, risk scores, causes of syncope and treatment modalities.

Study Design: This is a single center, prospective, observational study.

Place and Duration of Study: Department of Internal Medicine, Faculty of Medicine, Hospital das Clínicas, Federal University of Minas Gerais, Brazil, between February 2015 and February 2017.

Methodology: We included 375 consecutive patients, 203 men and mean age of 52 years, hospitalized because of syncope. They underwent clinical evaluation, the laboratory tests, and the calculation of Martin, OESIL and EGSYS scores.

Results: 114 patients had chagasic cardiomyopathy. The causes of syncope due to arrhythmia were ventricular tachycardia in 127 patients (66.1% men), supraventricular in 117 (63.2% women) and bradyarrhythmias in 56 patients (66.1% men), p<0.0001. Odds ratio for ventricular tachycardia in chagasic patients was 8.78 (95% IC: 5.33-14.46). Heart disease was predominant among men (p=0.001), even among patients with Chagas' heart disease. Comparing male and female, median age was 57 versus 48 years (p=0.04) and ejection fraction was 53 versus 58% (p=0.03). Martin and OESIL scores were higher in males (p <0.0001). There was no difference in treatment. Applying the receiver operating characteristic curve for ventricular tachycardia, Martin score had the largest area under the curve (0.84), p <0.0001.

Conclusions: Men hospitalized for syncope were older, had more systolic ventricular dysfunction, and had higher Martin and OESIL scores. The main causes of syncope were ventricular tachycardia and bradyarrhythmias among men and supraventricular tachycardias among women.