Cerebral Blood Flow Dynamics in Neurogenic Orthostatic Hypotension: A Systematic Review and Meta-Analysis | Hypertension
BACKGROUND: Neurogenic orthostatic hypotension (nOH) causes pathological falls in standing blood pressure that may or may not be symptomatic. nOH also raises the risk of poor neurological outcomes irrespective of symptom presence, possibly reflecting subclinical cerebral hypoperfusion. Dynamic changes in cerebral blood flow velocity (CBFv) help infer how blood pressure fluctuations influence CBFv and cerebral autoregulation. Whether CBFv is impacted in nOH relative to related conditions without nOH and healthy controls (HC) remains unresolved. Whether nOH symptoms reflect greater CBFv falls is also unclear. This review aimed to compare CBFv between nOH and HC, nOH and disease-matched controls (eg, Parkinson disease±nOH), and between symptomatic and asymptomatic nOH. METHODS: Embase and MEDLINE were searched up to April 2024. Means, SDs, and sample sizes for supine and upright CBFv were extracted to generate standardized effect sizes (Hedge g). Random-effects modeling compared postinter
