Is neurocardiovascular instability a risk factor for cognitive decline and/or dementia? The science to date

Neurocardiovascular instability (NCVI) is defined as ‘age-related changes in blood pressure and heart-rate behaviour, predominantly resulting in hypotension and bradyarrhythmia’ The four most common presentations of NCVI are orthostatic hypotension (OH), carotid sinus hypersensitivity/syndrome (CSH/CSS), vasovagal syncope (VVS) and post-prandial hypotension (PPH), although there is considerable overlap between these conditions. The criteria for diagnosis of these syndromes are given in Table 1. Clinically, these conditions manifest as dizziness, falls, pre-syncope and syncope. Older people are more susceptible to NCVI because of age-related physiological changes in the cardiovascular system, the autonomic nervous system, and humoral control of blood pressure. These neurocardiovascular changes are further complicated by co-morbidity and polypharmacy in older people.