Syncope etiology and prognosis in patients aged over 35 years

Abstract

Aim. To explore the etiology and prognosis of newly-onset syncope in patients aged over 35 years. Material and methods. The study included 502 patients aged 36-90 years. Clinical characteristics, laboratory and instrumental data, syncope recurrence, all-cause and cardiovascular mortality outcomes were analyzed retrospect-tively, in regard to syncope etiology. The association of syncope etiology with all-cause and cardiovascular mortality was examined by Kaplan-Meier method; Cox models were used to adjust for demographic characteristics and co-morbidities. Results. Major syncope etiology groups included: reflex-mediated syncope in 14% of the patients, cardiac – in 10%, neurogenic – in 6%, and orthostatic – in 12%. Syncope etiology remained unexplained in 45% of the cases. Total mortality was higher than that for general population of the same age and sex, but similar after co-morbidity adjustment. Syncope etiology was not associated with co-morbidity-adjusted all-cause mortality. Cardiovascular mortality was significantly higher in patients with cardiac syncope, compared to individuals with unexplained syncope: adjusted hazard ratio [95% confidence interval] 2.44 [1,02­5,83] (p=0,044). Conclusion: The cause of newly-onset syncope can be identified in a half of the patients over 35 years. In this group, high mortality, irrespective of syncope etiology, is mainly explained by concomitant disease burden.

Keywords

• syncope
• elderly age
• mortality