Clinical Factors Affecting Symptom Recurrence in Patients with Syncope

PURPOSE: Recurrent syncope leads to poor functional status and psychiatric impairment in patients with syncope. The aim of the study was to prospectively analyze the risk factors attributed to syncope recurrence. MATERIALS AND METHODS: Between 2009 and 2010, 289 patients with all cause of syncope visited our institution. Syncope recurrences were followed for 1 year by telephone interview every 3 months. RESULTS: We diagnosed 181 (63%) patients with neurally mediated syncope (NMS), 39 (13%) with orthostatic hypotension, 34 (12%) with cardiac syncope, and 35 (12%) with unexplained syncope. During the 1-year follow-up period, 19 (6.6%) patients suffered recurrent syncope. Kaplan-Meier curves showed that recurrent syncope was observed more often in patients with unexplained syncope compared with those with NMS (p < 0.01), and also observed more often in patients with six previous syncopal episodes compared to those with fewer episodes (p = 0.02). Cox regression analysis showed that the recurrence of syncope was significantly associated with more than six previous syncopal episodes (HR 5.38, 95% CI 1.17-24.71, p = 0.03) and that there was a tendency for association between recurrence of syncope and unexplained syncope (HR 6.13, 95% CI 0.96-39.1, p = 0.05). CONCLUSIONS: Patients with previous frequent syncopal episodes or unexplained syncope had higher rates of syncope recurrence during the follow up period.