Worsening of Symptoms Before Presentation with Vasovagal Syncope

Much of the natural history of vasovagal syncope is unknown. We determined whether patients presenting for care have had a recently worsened syncope frequency. Methods and Results: We compared 208 subjects in the referral‐based Prevention of Syncope Trial (POST) and 122 subjects who fainted ≥1 in a community survey study. Their mean ages and gender proportions were similar. The POST population had a higher median lifetime syncope frequency (1.16 vs 0.12 spells/year, P < 0.0001) and more subjects began fainting at age ≥35 years (26% vs 6%, P < 0.0001). In POST, the median frequency of syncopal spells in the preceding year was higher than in all previous years (3 vs 0.57, P < 0.0001). POST subjects presented sooner after their first spell (median 11.0 vs 16.8 years, P = 0.0002), and after their last spell (median 0.3 vs 7.4 years, P < 0.0001). POST subjects ≥35 years old had a shorter history than similar community‐survey subjects (2.8 vs 14.9 y, P < 0.0001) and presented earlier after their first syncopal spell than POST subjects with a younger onset of syncope (median 2.8 vs 14.7 y, P < 0.0001), despite having fewer faints (median 6 vs 10, P = 0.0002). Conclusions: Many syncope patients present for care after a recent worsening of their frequency of syncope.