Arterial stiffness, specifically augmentation index (AIx), is an independent predictor of cardiovascular risk. Previous studies suggest that insulin infusion decreases AIx and that this response is attenuated in insulin resistance. Whether physiological postprandial insulinemia similarly affects AIx measurements, and whether insulin resistance modifies this response, has not been studied.
Seven relatively insulin-resistant and seven insulin-sensitive postmenopausal women received low-carbohydrate and high-carbohydrate high-fat meals on separate days. Glucose and insulin levels were measured for 360-min following meal consumption. AIx was measured by radial artery applanation tonometry at regular intervals postprandially.
Postprandial increases in glucose and insulin were greater following the high-carbohydrate high-fat meal in both insulin-sensitive and insulin-resistant subjects. AIx decreased in both groups following both meals. In insulin-sensitive subjects, the postprandial reduction (incremental area above the curve) in AIx was greater following the high-carbohydrate vs. low-carbohydrate high-fat meal (−6821±1089 vs. −3797±1171%·min, respectively, P=0.009). In contrast, in insulin-resistant subjects, postprandial AIx responses were similar following the meals, suggesting that insulin resistance is associated with impaired postprandial arterial relaxation.
This study demonstrates that the carbohydrate content of a meal, and, hence, the magnitude of the postprandial glucose and insulin responses it elicits, are important determinants of postprandial AIx measurements. The further observation that insulin resistance modified this effect raises the possibility that this phenomenon is a contributor to increased cardiovascular risk in insulin resistance. The results indicate that future studies of AIx need to control for the effects of these potentially confounding variables and that measurement of AIx should be standardized with respect to meals.
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- Aortic stiffness is an independent predictor of all-cause and cardiovascular mortality in hypertensive patients.Hypertension. 2001; 37: 1236-1241
- Arterial wave reflections and survival in end-stage renal failure.Hypertension. 2001; 38: 434-438
- Inhibition of basal nitric oxide synthesis increases aortic augmentation index and pulse wave velocity in vivo.Br J Clin Pharmacol. 2002; 53: 189-192
- Arterial stiffness.J Hypertens. 1999; 17: 1-4
- Noninvasive determination of age-related changes in the human arterial pulse.Circulation. 1989; 80: 1652-1659
- Noninvasive registration of the arterial pressure pulse waveform using high-fidelity applanation tonometry.J Vasc Med Biol. 1989; 1: 142-149
- Measurement and application of arterial stiffness in clinical research: focus on new methodologies and diabetes mellitus.Med Sci Monit. 2003; 9: RA81-RA89
- Augmentation index is associated with cardiovascular risk.J Hypertens. 2002; 20: 2407-2414
- Reflection in the arterial system and the risk of coronary heart disease.Am J Hypertens. 2002; 15: 405-409
- Arterial stiffness, wave reflections, and the risk of coronary artery disease.Circulation. 2004; 109: 184-189
- Beneficial postprandial effect of a small amount of alcohol on diabetes and cardiovascular risk factors: modification by insulin resistance.J Clin Endocrinol Metab. 2005; 90: 661-672
- Diminished wave reflection in the aorta. A novel physiological action of insulin on large blood vessels.Hypertension. 1999; 33: 1118-1122
- Marked resistance of the ability of insulin to decrease arterial stiffness characterizes human obesity.Diabetes. 1999; 48: 821-827
- Arterial stiffness is related to insulin resistance in nondiabetic hypertensive older adults.J Clin Endocrinol Metab. 2005; 90: 2823-2827
- Physical activity reduces genetic susceptibility to increased central systolic pressure augmentation: a study of female twins.J Am Coll Cardiol. 2003; 42: 264-270
- Resistance to acute insulin induced decreases in large artery stiffness accompanies the insulin resistance syndrome.J Clin Endocrinol Metab. 2001; 86: 5262-5268
- Relationship of adiposity to subclinical atherosclerosis in obese patients with type 2 diabetes.Obes Res. 2003; 11: 1597-1605
- Arterial compliance and distensibility are modulated by body composition in both men and women but by insulin sensitivity only in women.Diabetologia. 1999; 42: 214-221
- Associations of metabolic variables with arterial stiffness in type 2 diabetes mellitus: focus on insulin sensitivity and postprandial triglyceridemia.Eur J Clin Invest. 2003; 33: 307-315
- Stiffness indexes beta of the common carotid and femoral arteries are associated with insulin resistance in NIDDM.Diabetes Care. 1998; 21: 1178-1182
- Atherogenesis: a postprandial phenomenon.Circulation. 1979; 60: 473-485
- Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man.Diabetologia. 1985; 28: 412-419
- Insulin resistance increases circulating malondialdehyde-modified LDL and impairs endothelial function in healthy young men.Int J Cardiol. 2004; 97: 455-461
- Report of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus.Diabetes Care. 1997; 20: 1183-1197
- Pulse contour analysis and augmentation index: it's time to move beyond cuff blood pressure measurement.Am J Hypertens. 2005; 18: 1S-2S
- An analysis of the relationship between central aortic and peripheral upper limb pressure waves in man.Eur Heart J. 1993; 14: 160-167
- Use of radial artery applanation tonometry and a generalised transfer function to determine aortic pressure augmentation in subjects with treated hypertension.J Am Coll Cardiol. 1998; 32: 1214-1220
- Abdominal fat and insulin resistance in normal and overweight women: direct measurements reveal a strong relationship in subjects at both low and high risk of NIDDM.Diabetes. 1996; 45: 633-638
- Clinical applications of arterial stiffness. Task Force III: recommendations for user procedures.Am J Hypertens. 2002; 15: 445-452
- Insulin-mediated skeletal muscle vasodilation is nitric oxide dependent. A novel action of insulin to increase nitric oxide release.J Clin Invest. 1994; 94: 1172-1179
- Vascular function, insulin resistance and fatty acids.Diabetologia. 2002; 45: 623-634
- Insulin resistance is associated with impaired nitric oxide synthase (NOS) activity in skeletal muscle of Type 2 Diabetic subjects.J Clin Endocrinol Metab. 2005; 90: 1100-1105
- Pathophysiological implications of insulin resistance on vascular endothelial function.Diabet Med. 2003; 20: 255-268
Published online: May 04, 2006
Accepted: December 11, 2005
Received in revised form: October 12, 2005
Received: July 16, 2005
© 2006 Elsevier Ireland Ltd. Published by Elsevier Inc. All rights reserved.