Familial predisposition to vasovagal syncope

Objective A handful of studies suggest a familial predisposition to vasovagal syncope (WS) but the scope of information available to date is poor. The aim of our study was to evaluate the prevalence of vasovagal syncope and its familial occurrence in the young. Methods and results The studied group consisted of 281 women and 111 men, aged 18-32 years. Forty-seven per cent of the population had one brother or sister, and the mean number of individuals per family was 4.4 +/- 1.0. The questionnaire consisted of 30 questions regarding syncopal history. Syncope was reported in 32.1% of the patients studied (36.7% in women vs 20.7% in men; P<0.05), 29.1% of mothers, 16.8% of fathers, 30.9% of sisters and 14.2% of brothers. Logistic regression analysis revealed that positive history regarding the syncope in the whole group of students was related to the female gender (OR 2.17; Cl: 1.28 - 3.7), the history of a syncope in mother (OR 1.74; CI: 1.09-2.78) and the history of a syncope in father (OR 2.22; Cl: 1.28-3.86; P < 0.001). Conclusions A positive history of syncope in male relatives increases the risk of syncope in men and women, whereas a positive history of syncope in female relatives increases the risk of syncope in women only. Female gender independently of the family history increases the risk of syncope. The genetics of the vasovagal syncope could be polygenic but the mechanisms of a transmission remain unclear to date.