Age and sex differences in vasovagal syncope: triggers, clinical presentation, prodromal symptoms, and head-up tilt test results

Aims Previous studies show inconsistencies in vasovagal syncope (VVS) symptoms and haemodynamic responses across age and sex groups, with limited evaluation of tilt test results. This study comprehensively examines differences in triggers, prodromal and syncopal symptoms, and head-up tilt test (HUTT) responses among VVS patients by age and sex providing new insights. Methods and results We analysed data from Syncope Unit of Tehran Heart Center, including adults (≥18 years) with suspected VVS diagnosis based on clinical history and physical exams according to syncope guidelines, to explore sex- and age-specific clinical features and HUTT outcomes. The study included 1914 VVS patients (mean age: 46.6 ± 17.8; 51.3% male). Males were more likely to experience first-time syncope (31.6% vs. 19.8%, P < 0.001), whereas females had more recurrent episodes (37.5% vs. 31.2%, P < 0.01) and reported more identifiable triggers. During the HUTT passive phase, females exhibited a greater diastolic blood pressure drop [49.5 ± 12.2 vs. 34.4 ± 17.2, P = 0.012], while in the active phase, they experienced a more pronounced heart rate reduction 39.7 ± 26.9 vs. 30.2 ± 23.3, P < 0.001. Cardioinhibitory syncope was more prevalent in younger patients, with over two-thirds of cases occurring in individuals under 50 years old, and its frequency declined with age. In contrast, vasodepressor syncope peaked in the 51–70 age group. Agreement between spontaneous and HUTT-induced syncope was low (κ = 0.06–0.32). Conclusion Age and sex shape VVS presentation, triggers, and haemodynamic response, emphasizing the need for demographic considerations in management and the limitations of HUTT.