Postprandial Vascular Reactivity in Obese and Normal Weight Young Adults

• Published in: Obesity (Silver Spring, Md.) Md.), 2010-05, Vol.18 (5), p.945-951
• Main Authors: Ayer, Julian G, Harmer, Jason A, Steinbeck, Katherine, Celermajer, David S
• Format: Article
• Language: English
• Subjects: Adult; Anthropometry; arms (limbs); blood; Blood Flow Velocity - physiology; Blood Glucose; Blood pressure; Blood Pressure - physiology; Body Mass Index; Brachial Artery - physiopathology; Cardiovascular disease; Cholesterol; Dietary Fats; Fatty acids; Female; Glucose; Heart rate; Heart Rate - physiology; high density lipoprotein cholesterol; Hospitals; Humans; Insulin; Insulin - blood; Male; men; Menstruation; Metabolism; Obesity; Obesity - metabolism; Obesity - physiopathology; Patient Selection; Physiology; Postprandial Period - physiology; postprandial state; Regional Blood Flow; risk; Statistics, Nonparametric; triacylglycerols; Triglycerides; Waist Circumference; Waist-Hip Ratio; Young adults
• ISSN: 1930-7381; 1930-739X
• DOI: 10.1038/oby.2009.331

As humans spend a significant amount of time in the postprandial state, we examined whether vascular reactivity (a key indicator of cardiovascular health) was different after a high-fat meal in 11 obese (median BMI 46.4, age 32.1 ± 6.3 years, 7 men) and 11 normal weight (median BMI 22.6) age- and sex-matched controls. At baseline and 1 and 3 h postmeal, blood pressure (BP), heart rate (HR), reactive hyperemia peripheral artery tonometry (RH-PAT) index, radial augmentation index adjusted for HR (AIx75), brachial pulse wave velocity (PWVb), glucose, insulin, total and high-density lipoprotein (HDL) cholesterol, and triglycerides were measured. Brachial flow-mediated dilatation (FMD) and, by venous plethysmography, resting and hyperemic forearm blood flows (FBFs) were measured at baseline and 3 h. At baseline, obese subjects had higher systolic BP, HR, resting FBF, insulin and equivalent FMD, RH-PAT, hyperemic FBF, AIx75, PWVb, glucose, total cholesterol, triglycerides, and lower HDL cholesterol. In obese and lean subjects, FMD at baseline and 3 h was not significantly different (6.2 ± 1.7 to 5.8 ± 4.3% for obese and 4.7 ± 4.1 to 4.3 ± 3.9% for normal weight, P = 0.975 for group × time). The meal did not produce significant changes in RH-PAT, hyperemic FBF, and PWVb in either group (P > 0.1 for the effect of time and for group × time interactions). In conclusion, the vascular responses to a high-fat meal are similar in obese and normal weight young adults. An exaggerated alteration in postprandial vascular reactivity is thus unlikely to contribute importantly to the increased cardiovascular risk of obesity.