Geriatric hypotensive syndromes are not explained by cardiovascular autonomic dysfunction alone

Though highly prevalent, the pathophysiology of orthostatic hypotension (OH), postprandial hypotension (PPH), and carotid sinus hypersensitivity (CSH) are rarely studied together. Therefore, we conducted such a comprehensive study focusing on the common role of the cardiovascular autonomic system. We hypothesized that in geriatric patients, OH, PPH, and CSH are manifestations of cardiovascular autonomic dysfunction and investigated state-of-the-art cardiovascular autonomic function indices in a group of geriatric falls or syncope patients. In a cross-sectional study of 203 consecutive eligible falls clinic patients, we compared heart rate variability (HRV), blood pressure variability (BPV), and baroreflex sensitivity (BRS) as potential autonomic function determinants of the three different hypotensive syndromes. OH, PPH, and CSH were diagnosed in 53%, 57%, and 50% of the patients, respectively. In a population relevant for geriatric practice, we found no differences in HRV, BPV, and BRS between patients with and without OH, with and without PPH, and with and without CSH, respectively, nor between patients with and without falls, dizziness, or syncope as presenting symptom, respectively. In geriatric patients with hypotensive syndromes, cardiovascular autonomic function as measured by HRV, BPV, and BRS is comparable to patients without such syndromes. These findings argue against a single or dominant etiological factor, that is, cardiac autonomic dysfunction and underline the structured, broad, and multifactorial approach to elderly patients with falls and/or syncope as proposed in the current evidence-based syncope guidelines.