Frida Dangardt

Omega-3 fatty acid supplementation improves vascular function and reduces inflammation in obese adolescents

OBJECTIVE Compared to normal weight adolescents, obese adolescents have lower serum omega-3 (n-3) polyunsaturated fatty acid (PUFA) concentrations, augmented inflammatory activity and endothelial dysfunction. We wanted to assess whether n-3 supplementation increases the serum n-3 PUFA concentration, improves vascular function and morphology, and lowers inflammation in obese adolescents. METHODS Twenty-five obese adolescents (14 females, 11 males, age 15.7±1.0 years, BMI 33.8±3.9) were randomized to receive capsules containing either 1.2g/day n-3 or placebo for 3 months. The study was performed using a double-blind, cross-over design with a 6-week washout period. Anthropometry, blood pressure measurements and fasting blood samples were obtained before and after each treatment period. The vascular structure and function was measured after each treatment period. RESULTS The serum n-3 PUFA concentration increased with n-3 treatment. The reactive hyperemia response improved with n-3 treatment compared to placebo (p<0.01). N-3 supplementation also decreased the lymphocyte, monocyte, TNF-α, IL-6 and IL-1β levels. No difference was found in the total cholesterol, triacylglycerol, HDL cholesterol, anthropometry, blood pressure, pulse wave velocity or vascular structure between the two treatment groups. CONCLUSION Daily supplementation with n-3 capsules increases the serum n-3 PUFA concentration, improves vascular function, and lowers the degree of inflammation in obese adolescents.

Obese children show increased intimal wall thickness and decreased pulse wave velocity

Objective:  Childhood obesity confers an increased risk of vascular changes and adult cardiovascular disease. Using a high‐resolution ultrasound technique that enables separation of intimal and medial layers, we examined the intimal thickness (IT) and intimal–medial thickness (IMT) of radial (RA) and dorsal pedal (DPA) arteries and the pulse wave velocity (PWV) in overweight/obese children and adolescents and in healthy subjects.

Increasing Peripheral Artery Intima Thickness From Childhood to Seniority

Background—Using new, very high-resolution ultrasound biomicroscopy, we examined the thickness of artificial layers of silicone and intima thickness (IT) of radial and anterior tibial arteries in healthy subjects and in patients with vascular disease. Methods and Results—Silicone layers of varying thicknesses and mesenteric artery specimens obtained from 18 patients undergoing colectomy were measured by both ultrasound biomicroscopy (55 MHz) and morphometry. There was high correlation (r>0.9; P<0.0001) between IT and intima area versus ultrasound biomicroscopy. In 90 healthy subjects (aged between 10 and 90 years), radial and anterior tibial arterial IT and intima-media thickness were measured, as was carotid intima-media thickness in 56 of these subjects. Age was strongly related with both media thickness and IT of both peripheral arteries. Correlations were found between carotid intima-media thickness and both radial and anterior tibial IT/intima-media thickness (r=0.44 to 0.53; P<0.0001). The IT-to-lumen diameter ratio increased with age and was larger at all ages in the anterior tibial artery (0.067±0.034) versus the radial artery (0.036±0.012; P<0.0001). A thicker radial intimal layer was found in patients with peripheral artery disease. Conclusion—This study is the first to our knowledge in humans to show the feasibility of measuring IT of the radial and anterior tibial arteries using very high-resolution ultrasound. IT progresses with age, and the IT-to-lumen diameter ratio is largest in the arteries of the foot. Assessment of IT by ultrasound biomicroscopy may aid in detecting early peripheral vascular abnormalities.

Has the leaning tower of presumed health benefits from 'moderate' alcohol use finally collapsed?

The evolving epidemiological literature, including improved methodology for assessing causality in observational studies, is raising doubts about whether moderate alcohol consumption has a protective effect on health.

Anger, depression and anxiety associated with endothelial function in childhood and adolescence

Objective Psychosocial adversity is a risk factor for cardiovascular disease (CVD) in adults. The authors assessed associations of reactive hyperaemia peripheral arterial tonometry (RH-PAT), a measure of endothelial function predictive of CVD, with self-assessed psychological health among school children. Methods A total of 248 healthy school children (mean (SD) age 14.0 (1.0); 136 girls and 112 boys) underwent RH-PAT testing. They completed the Beck Youth Inventories (BYI) of emotional and social impairment scales, which is used to screen for depression, anxiety, anger and disruptive behaviour. Results No sex differences were observed for the RH-PAT score. Statistically significant differences were observed for the BYI scores; girls had higher scores for depression, anger and anxiety. Among the girls, there were statistically significant associations between lower RH-PAT scores and higher scores for anger (B coefficient=−0.100, p=0.040), depression (−0.108, p=0.009) and anxiety (−0.138, p=0.039) after adjustment for age. Among the boys, disruptive behaviour was associated with higher RH-PAT scores (0.09, p=0.006). Conclusions The girls have higher levels of self-assessed anger; depression and anxiety compared with the boys, and these characteristics are associated with lower RH-PAT scores, indicating attenuated endothelial function. Among the boys, disruptive behaviour was associated with better endothelial function. Although psychological ill-health is associated with impaired endothelial function and CVD among adults, such processes may also be relevant to children. Psychosocial adversity in childhood might be a risk factor for subsequent CVD.

Age- and sex-related differences in vascular function and vascular response to mental stress. Longitudinal and cross-sectional studies in a cohort of healthy children and adolescents.

OBJECTIVE Limited data, especially from longitudinal studies, are available regarding vascular health assessment in childhood. In this study, we performed longitudinal and cross-sectional studies in healthy children and adolescents to investigate age- and sex-related differences in vascular functions and vascular response to mental stress. METHODS Pulse wave velocity (PWV) was measured by tonometry. Endothelial function and vascular response to mental arithmetic test were assessed using a peripheral artery tonometry device. Data were obtained in 162 adolescents (mean age of 17 years, 94 girls) in a 3-year follow-up study and 241 children (mean age of 10 years, 115 girls) in a first-time investigation. Physical activity was assessed in adolescents by a self-report questionnaire. RESULTS Our 3-year follow-up study revealed that the increased PWV was greater in male adolescents (0.79±0.79m/s) than in females (0.27±0.89m/s, p<0.001). Adolescents who reported decreased physical activity over the 3-year period had increased arterial stiffness. Comparing the cross-sectional data, we found that sex-related differences in reactive hyperemic response was more apparent by evaluating the overall response curve than measuring the reactive hyperemic index from one arbitrary time point, with lower peak response and smaller area-under-curve found in boys. Moreover, we found that, in response to mental stress, male adolescents had a more vasoconstrictive response, followed by a less vasodilatory response, and needed longer time to return to baseline level than the females. CONCLUSION These findings suggest that boys are likely to have adverse changes in vascular health earlier than the age-matched girls.

Reduced cardiac vagal activity in obese children and adolescents.

Objective:  Obese children present with various cardiovascular risk factors affecting their future health. In adults, cardiac autonomic function is a major risk factor, predicting cardiovascular morbidity and mortality. We hypothesized that obese children and adolescents had a lower cardiac vagal activity than lean subjects. We measured cardiac spontaneous baroreflex sensitivity (BRS), reflecting the dynamic regulation of cardiac vagal function, in large groups of obese and lean young individuals.

High Physiological Omega-3 Fatty Acid Supplementation Affects Muscle Fatty Acid Composition and Glucose and Insulin Homeostasis in Obese Adolescents

Obese adolescents have high concentrations of saturated fatty acids and low omega-3 long-chain polyunsaturated fatty acids (LCUFAs) in plasma phospholipids. We aimed to investigate effects of omega-3 LCPUFA supplementation to obese adolescents on skeletal muscle lipids and glucose and insulin homeostasis. Twenty-five obese adolescents (14–17 years old, 14 females) completed a randomized double-blind crossover study supplying capsules containing either 1.2 g omega-3 LCPUFAs or placebo, for 3 months each with a six-week washout period. Fasting blood glucose, insulin, leptin, adiponectin, and lipids were measured. Intravenous glucose tolerance test (IVGTT) and euglycemic-hyperinsulinemic clamp were performed, and skeletal muscle biopsies were obtained at the end of each period. The concentrations of EPA, DHA, and total omega-3 PUFA in muscle phospholipids increased in both sexes. In the females, omega-3 LCPUFA supplementation improved glucose tolerance by 39% (P = 0.04) and restored insulin concentration by 34% (P = 0.02) during IVGTT. Insulin sensitivity improved 17% (P = 0.07). In males, none of these parameters was influenced by omega-3 supplementation. Thus, three months of supplementation of omega-3 LCPUFA improved glucose and insulin homeostasis in obese girls without influencing body weight.

Increased rate of arterial stiffening with obesity in adolescents: a five-year follow-up study.

Background We prospectively and longitudinally determined the effects of childhood obesity on arterial stiffening and vascular wall changes. Changes in arterial stiffness measured as pulse wave velocity (PWV) and vascular morphology of the radial (RA) and dorsal pedal arteries (DPA) were examined in obese adolescents compared to lean subjects in a 5-year follow-up study. Methodology/Principal Findings A total of 28 obese subjects and 14 lean controls participated in both baseline (14 years old) and follow-up studies. PWV was measured by tonometer (SphygmoCor®) and recorded at RA and carotid artery, respectively. Intima thickness (IT), intima-media thickness (IMT) and RA and DPA diameters were measured using high-resolution ultrasound (Vevo 770™). Over the course of 5 years, PWV increased by 25% in the obese subjects as compared to 3% in the controls (p = 0.01). Diastolic blood pressure (DBP) increased by 23% in the obese subjects as opposed to 6% in controls (p = 0.009). BMI increased similarly in both groups, as did the IT and IMT. The change in PWV was strongly associated to the baseline BMI z -score (r = 0.51, p<0.001), as was the change in DBP (r = 0.50, p = 0.001). Conclusions/Significance During the transition from early to late adolescence, there was a general increase in arterial stiffness, which was aggravated by childhood obesity. The increase in arterial stiffness and DBP after 5 years was closely correlated to the baseline BMI z -score, indicating that childhood obesity has an adverse impact on vascular adaptation.

High levels of soluble intercellular adhesion molecule-1, insulin resistance and saturated fatty acids are associated with endothelial dysfunction in healthy adolescents

OBJECTIVE Atherosclerosis begins and progresses during childhood and adolescence. Endothelial dysfunction is one of the earliest abnormalities that can be detected in the development of atherosclerosis. As the determinants of endothelial function in childhood are unknown, we investigated the influence of cardiovascular risk factors on endothelial function in a cohort of healthy adolescents. METHODS A total of 257 adolescents (age: 14.5 + or - 1.0 years, 138 girls) participated in this study. Endothelial function was measured as reactive hyperemic index (RHI) using a fingertip peripheral arterial tonometry device. Blood samples were collected for analysis of lipids, insulin, glucose, fatty acid composition of plasma phospholipids, and markers of inflammation and endothelial function. RESULTS There was no gender difference in RHI. Boys had higher plasma level of vascular cellular adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), P-selectin and monocyte chemoattractant protein-1, and lower level of insulin, total cholesterol, high-density lipoprotein-cholesterol (HDL), low-density lipoprotein-cholesterol (LDL), ApoA1, ApoB, and docosahexaenoic acid of plasma phospholipids than girls. There was no gender difference regarding triacylglycerol, triacylglycerol/HDL, LDL/HDL and ApoB/ApoA. The RHI was inversely associated with plasma ICAM-1 (p=0.0003), HOMA index for insulin resistance (HOMA-IR, p=0.001) and saturated fatty acids of plasma phospholipids (SFA, p=0.001). The associations remained significant after adjusting for age, height, BMI-z-score, sex, blood pressure, HDL and smoking. CONCLUSION In healthy adolescents impaired endothelial function is significantly associated with high level of soluble ICAM-1, HOMA-IR and SFA.