Acute effects of a mixed meal on arterial stiffness and central hemodynamics in healthy adults.
BACKGROUND
Elevated central pressures and arterial stiffness are associated with increased peripheral resistance and higher sympathetic nervous system activity. Additionally, consumption of a meal is known to be sympathoexcitatory. However, the acute effects of a meal on aortic wave reflection and stiffness are unknown. Therefore, we tested the hypothesis that aortic wave reflection and stiffness would increase after a meal.


METHODS
We examined these effects using high-fidelity radial arterial pressure waveforms and carotid-femoral pulse wave velocity measured noninvasively by applanation tonometry before and 60 and 180 minutes after ingestion of a liquid mixed meal (Ensure; 40% of daily energy expenditure) in 17 healthy adults (9 men/8 women; aged 29 ± 2 years). Additionally, we measured sympathetic activity by microneurography at baseline and up to 60 minutes after the meal.


RESULTS
Although sympathetic activity increased after the meal, both peripheral and central pressures were reduced at 180 minutes from baseline (all P < 0.05). Contrary to our hypothesis, augmentation index (14% ± 3% vs. 2% ± 3% vs. 8% ± 3%), augmentation index normalized for heart rate (8% ± 3% vs. -3% ± 3% vs. 3% ± 3%), augmented pressure (5 ± 1 mm Hg vs. 1 ± 1 mm Hg vs. 3 ± 1 mm Hg), and pulse wave velocity (7.1 ± 0.2 m/s vs. 6.7 ± 0.2 m/s vs. 6.7 ± 0.1 m/s) were substantially reduced at 60 and 180 minutes after the meal (all P < 0.05).


CONCLUSIONS
Taken together, our results suggest that a liquid mixed meal acutely decreases central hemodynamics and arterial stiffness in healthy adults, which may be a result of meal-related increases in insulin and/or visceral vasodilation.
Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota.
Jennifer L
JL
Taylor
Timothy B
TB
Curry
Luke J
LJ
Matzek
Michael J
MJ
Joyner
Darren P
DP
Casey
D000328:Adult; D001794:Blood Pressure; D004435:Eating; D005260:Female; D064368:Healthy Volunteers; D006339:Heart Rate; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008365:Manometry; D062407:Meals; D019518:Postprandial Period; D063177:Pulse Wave Analysis; D013564:Sympathetic Nervous System / Q000502:physiology; D013997:Time Factors; D059289:Vascular Stiffness
aortic pressure; blood pressure; hypertension; mixed meal; pulse wave velocity; sympathetic nerve activity; wave reflection.