P89 3 HOURS UNINTERRUPTED SITTING INCREASES CEREBROVASCULAR RESISTANCE AND REDUCES CEREBRAL BLOOD FLOW IN SUBJECTS WITH INCREASED CARDIOVASCULAR RISK

DOI

10.1016/j.artres.2018.10.142How to use a DOI?

Abstract

Background: Sedentary behavior has deleterious effects on cardiovascular risk. Uninterrupted sitting is associated with an impaired peripheral blood flow and vascular function. However, the relation between cerebrovascular flow and sedentary behavior is currently unknown. Impaired cerebrovascular flow and function are associated with impaired cognitive function and dementia. Therefore, this study investigated the effects of a prolonged sedentary bout on cerebrovascular flow and function.

Methods: 19 participants with increased cardiovascular risk (age > 55 years, BMI 28 kg m⁻² or hypertension) underwent a 3 hours uninterrupted sitting intervention. At baseline and after intervention middle cerebral artery blood flow velocity (MCAv) was measured using transcranial Doppler. Cerebrovascular resistance index (CVRi) was expressed as the ratio of MAP:MCAv.

Results: Due to technical difficulties, three participants were excluded from analysis, leaving 16 participants (age = 64 ± 5 years, BMI = 30.5 ± 4.5 kg m⁻²). MCAv decreased after 3 hours sitting from 50.4 cm⁻¹ s⁻¹ (95% CI 47.0 – 53.7) to 46.9 cm⁻¹ s⁻¹ (95% CI 43.3 – 50.4) cm s⁻¹ (mean difference = 3.5 cm s⁻¹ (95% CI -0.1 – 7.0), P = 0.055). This was accompanied by an increase in CVRi (2.08 ± 0.35 cm⁻¹ s⁻¹ to 2.39 ± 0.56 cm⁻¹ s⁻¹, P = 0.016).

Conclusions: Our results indicate that prolonged sedentary bouts impair cerebrovascular blood flow and stress the importance of frequently interrupting sitting periods in order to maintain adequate cerebral blood flow. Future studies should further investigate the impact of sedentary behaviour in the context of cerebrovascular diseases.

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TY  - JOUR
AU  - Yvonne Hartman
PY  - 2018
DA  - 2018/12/04
TI  - P89 3 HOURS UNINTERRUPTED SITTING INCREASES CEREBROVASCULAR RESISTANCE AND REDUCES CEREBRAL BLOOD FLOW IN SUBJECTS WITH INCREASED CARDIOVASCULAR RISK
JO  - Artery Research
SP  - 104
EP  - 104
VL  - 24
IS  - C
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2018.10.142
DO  - 10.1016/j.artres.2018.10.142
ID  - Hartman2018
ER  -