Etiology of Syncope and Unexplained Falls in Elderly Adults With Dementia: Syncope and Dementia (SYD) Study

Andrea Ungar, MD, PhD; Chiara Mussi, MD, PhD; Alice Ceccofiglio, MD; Giuseppe Bellelli, MD, PhD; Franco Nicosia, MD; Mario Bo, MD; Daniela Riccio, MD; Anna Maria Martone, MD; Livia Guadagno, MD; Gabriele Noro, MD; Giulia Ghidoni, MD; Martina Rafanelli, MD; Niccolò Marchionni, MD; Pasquale Abete, MD, PhD


J Am Geriatr Soc. 2016;64(8):1567-1573. 

In This Article

Abstract and Introduction


Objectives: To investigate the etiology of transient loss of consciousness (T-LOC) suspected to be syncope and unexplained falls in elderly adults with dementia.

Design: Prospective, observational, multicenter study.

Setting: Acute care wards, syncope units or centers for the diagnosis of dementia.

Participants: Individuals aged 65 and older with a diagnosis of dementia and one or more episodes of T-LOC of a suspected syncopal nature or unexplained falls during the previous 3 months were enrolled.

Measurements: The causes of T-LOC suspected to be syncope and unexplained falls were evaluated using a simplified protocol based on European Society of Cardiology guidelines.

Results: Of 357 individuals enrolled, 181 (50.7%) had been referred for T-LOC suspected to be syncope, 166 (46.5%) for unexplained falls, and 10 (2.8%) for both. An initially suspected diagnosis of syncope was confirmed in 158 (87.3%), and syncope was identified as the cause of the event in 75 (45.2%) of those referred for unexplained falls. Orthostatic hypotension was the cause of the event in 117 of 242 (48.3%) participants with a final diagnosis of syncope.

Conclusion: The simplified syncope diagnostic protocol can be used in elderly people with dementia referred for suspected syncope or unexplained falls. Unexplained falls may mask a diagnosis of syncope or pseudosyncope in almost 50% of cases. Given the high prevalence of orthostatic syncope in participants (~50%), a systematic reappraisal of drugs potentially responsible for orthostatic hypotension is warranted.


Falling is a major cause of morbidity and mortality in the elderly general population[1] and the primary cause of hospitalization in those with dementia.[2] The risk of falling is eight times as high in elderly adults with dementia as in their cognitively intact counterparts and is frequently related to syncope.[3] Although neuroautonomic evaluation is a reliable diagnostic tool in cognitively impaired elderly adults with unexplained falls,[4] individuals with dementia are a particular clinical subset in which suspected syncope is less likely to be fully investigated. This may be because of several factors, ranging from difficulty collecting information on falls in individuals with dementia to an ageist attitude that tends to underestimate the relevance of falls and syncope in older persons, particularly those that are cognitively impaired.[5] However, identification of the causes of falls and of individuals with syncope-related falls may have important clinical and therapeutic implications that, in turn, may reduce the burden of falls-related morbidity and mortality in this subset of frequent fallers.

A prospective, observational, multicenter study was conducted to define the etiology of syncope and unexplained falls in elderly adults with dementia using a simplified protocol based on European Society of Cardiology (ESC) guidelines.[6]