Cerebral autoregulation in orthostatic hypotension and falls among older adults: a community-based exploratory study.

Abstract

Background: Orthostatic hypotension (OH) is prevalent in older adults and is often associated with falls. However, the presence or absence of symptoms in OH may be mediated by cerebral autoregulation, which helps maintain cerebral perfusion during blood pressure fluctuations.

Methods: We recruited 40 older adults (aged ≥ 55 years) from the Malaysian Elders Longitudinal Research (MELoR) cohort. Participants underwent cerebral blood flow velocity monitoring using transcranial Doppler ultrasonography and beat-to-beat blood pressure recording. Three protocols were used: active stand, mental arithmetic, and Valsalva manoeuvre. Participants were categorized, based on OH (≥ 30 mmHg systolic drop) and fall history, into four groups. Cerebrovascular resistance (CVR) was derived and analysed.

Results: Participants with OH but no history of falls demonstrated preserved autoregulatory responses, as reflected by adaptive reductions in CVR. In contrast, fallers-regardless of OH status-had impaired CVR modulation. Significant group differences were found during the active stand test at 165 s and 180 s (p < 0.05).

Conclusion: Preserved cerebral autoregulation may protect older adults with OH from symptomatic manifestations such as falls. Targeting cerebral autoregulation could offer novel approaches for preventing falls in this population.