Serum resistin and inflammatory and endothelial activation markers in obese adolescents.

OBJECTIVES: To assess the level of serum resistin in obese and lean children and to establish a relationship with circulating inflammatory and vascular markers. STUDY DESIGN: This is a cross-sectional study including 67 obese and 62 lean children (mean age 10.9 ± 2.8 years, age range 5.4-16.6 years). We assessed circulating hormones (insulin, leptin, insulin-like growth factor 1), markers of inflammation (resistin, high sensitivity C-reactive protein, interleukin-6, chemokine ligand 2), and endothelial cell activation (vascular and intercellular adhesion molecules: vascular cell adhesion molecule 1 and intercellular adhesion molecule; E-selectin; P-selectin; endothelin 1). RESULTS: Body weight, body mass index (BMI), insulin, leptin, high-sensitivity C-reactive protein, vascular adhesion molecule 1, and E-selectin levels were significantly higher in obese than in lean subjects. Resistin was similar among the groups in the prepubertal period, but increased significantly in the obese adolescents (18.6 ± 24.9) compared with lean subjects (7.9 ± 10.7 ng/mL; P = .038). Resistin was not associated with BMI z score (P > .05). Subjects with resistin levels above 9 (ng/mL) had higher concentration of interleukin-6, chemokine ligand 2, endothelin-1, and insulin-like growth factor 1 but not of leptin, insulin, or BMI. CONCLUSION: Resistin was increased in obese adolescents independently of the quantity of the adipose tissue. In this population, increased resistin levels were related to inflammation and endothelial activation. We may hypothesize that interventions aiming to diminish resistin expression may slow down atherogenesis in adolescents.

Preclinical noninvasive markers of atherosclerosis in children and adolescents with type 1 diabetes are influenced by physical activity.

OBJECTIVES: To measure preclinical noninvasive markers of atherosclerosis in youth with type 1 diabetes (T1DM), and to determine their associations between physical activity level and cardiorespiratory fitness (maximal oxygen consumption [VO2max]). STUDY DESIGN: This was a cross-sectional study including 32 patients with T1DM and 42 healthy subjects aged 6 to 17 years. Main outcome measures included arterial flow-mediated dilation (FMD) and intima-media thickness with high-resolution ultrasonography; physical activity by accelerometer (valid 26 patients with T1DM, 35 healthy subjects) and VO2max. RESULTS: Compared with healthy control subjects, patients with T1DM had higher intima-media thickness (mean 0.50 mm [0.48-0.52, 95% CI] vs 0.48 [0.47-0.49], P=.02) and reduced FMD (4.9% [4.1%-5.7%] vs 7.3 [6.4-8.1], P=.001), VO2max (45.5 mL/kg/min [43.0-48.0] vs 48.7 [46.7-50.6], P

Associations among obesity, blood pressure, and left ventricular mass.

OBJECTIVES: To measure resting and ambulatory systemic blood pressure (BP) and left ventricular mass (LVM) in prepubertal obese and lean children and to determine their relationships. STUDY DESIGN: Cross-sectional study including 44 obese and 22 lean prepubertal children (mean age 8.8 +/- 1.5 years). We measured casual and 24-hour ambulatory BP, LVM and LVM index (LVMI) by echocardiography, and whole body lean tissue and fat mass by dual-energy X-ray absorptiometry. RESULTS: Mean 24-hour systolic BP (124.8 +/- 14.2 vs 105.5 +/- 8.8 mm Hg), diastolic BP (72.8 +/- 7.3 vs 62.7 +/- 3.8 mm Hg), and LVMI (36.1 +/- 5.8 vs 30.9 +/- 5.7, g x m(-2.7)) were significantly higher in obese than in lean subjects. Systolic ambulatory hypertension was present in 47.6% of obese children, and casual BP was normal in 55% of those cases. Body fatness, lean tissue mass, and 24-hour BP correlated positively with LVMI. When adjusted for body fatness, LVMI was only associated with 24-hour systolic BP (adjusted R(2) = 15.9%; P = .001). CONCLUSIONS: Ambulatory systemic hypertension and increased LVM are found in obese children. Left ventricular mass is partially determined by systemic BP. We conclude that prevention and treatment of childhood obesity should be initiated as early as possible to prevent the premature development of hypertension and end-stage organ damage.