Post-event sleep and tiredness in epilepsy versus vasovagal syncope

Differentiating epileptic seizures from vasovagal syncope (VVS) in children is challenging. Post-event symptoms, especially sleep and tiredness, may aid diagnosis. While post-event sleep is common in epilepsy, its occurrence in VVS is less understood. This study examines post-event sleep and tiredness duration in epilepsy and VVS.

This retrospective study analysed 272 patients (160 epilepsy, 112 VVS) from a seizure clinic (2017-2025). Post-event sleep and duration of tiredness occurrence were recorded from patient histories and follow-ups.

All patients with epilepsy had postictal tiredness ≥2 h, with 49 % lasting >4 h. In contrast, 55.5 % of VVS patients had no tiredness or tiredness for <2 h. Sleep or prolonged fatigue is much more common following seizures in epilepsy (94 %) than in VVS (21 %). All VVS cases showing recovery sleep were associated with syncopal motor phenomena.

The absence or brief fatigue following a loss of consciousness event strongly suggests VVS, provided that the history indicates no motor phenomena. In contrast, post-event sleep and/or prolonged fatigue is a key indicator that the event may be an epileptic seizure or a syncopal episode with motor activity.