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Published on: December 22, 2016
Cerebrovascular pulsatility in patients with sleep-disordered breathing
Alberto R Ramos1, Digna Cabral, David J Lee
1Department of Neurology, Miller School of Medicine, University of Miami, 1120 NW 14th Street, Suite 1350, Miami, FL 33136, USA. aramos@med.miami.edu
This study found that pulsatility index (PI), a marker for cerebral small vessel disease, is associated with sleep-disordered breathing (SDB). Increased PI in SDB patients may help assess cerebral hemodynamics.
Area of Science:
- Neurology
- Sleep Medicine
- Vascular Medicine
Background:
- Sleep-disordered breathing (SDB) is linked to various health issues.
- Cerebral small vessel disease (CSVD) affects brain health.
- Pulsatility index (PI) measured by transcranial Doppler ultrasound (TCD) can indicate CSVD.
Purpose of the Study:
- To determine the association between PI and SDB.
- To investigate PI as a potential surrogate for CSVD in SDB patients.
Main Methods:
- A TCD study was performed on 19 patients evaluated for SDB.
- Polysomnography was used to assess SDB severity (apnea-hypopnea index, AHI).
- Spearman's rank correlation and nonparametric regression analyzed the relationship between AHI, oxygen levels, and PI.
Main Results:
- PI correlated significantly with AHI (rho=0.44, p=0.004) and age (rho=0.57, p=0.001).
- Nonparametric regression, adjusting for age, confirmed a positive association between AHI and PI (p=0.002).
- No significant relation was found between oxygen nadir and PI.
Conclusions:
- Increased PI was observed in patients with SDB during wakefulness.
- PI may serve as an estimate of CSVD in SDB patients.
- TCD offers a clinically relevant method for evaluating cerebral hemodynamics in SDB.
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