Fat mass and vascular health in overweight/obese children.

BACKGROUND AND AIM: Childhood obesity is one of the most serious public health challenges of the 21st century. Body mass index (BMI), the most widely used marker of body fatness, has serious limitations, particularly in children, since it does not accurately discriminate between lean and fat mass. Aim of our study was to investigate if the estimate of fat mass, as derived by a new prediction model, was associated with carotid intima media thickness (IMT) and the cross-sectional area of the intima media complex (CSA-IMC) in overweight or obese children. METHODS AND RESULTS: As many as 375 overweight/obese Italian children, 54.7% males, aged 5-15 years, admitted to a tertiary care hospital, were consecutively enrolled in a study on cardiovascular markers of atherosclerosis. All children underwent an ultrasound carotid examination. Mean weight was 62.2 ± 20.8 Kg and fat-mass was 26.2 ± 10.7 Kg. Multiple regression analyses showed a significant association of fat mass with carotid IMT (ß 0.156, p 0.01) and CSA-IMC (ß 0.216, p < 0.001); these associations remained significant after controlling for the main cardiovascular risk factors (age, sex, blood pressure, HOMA-index, triglycerides, LDL-cholesterol, HDL-cholesterol, birth weight and high-sensitivity C-reactive protein). CONCLUSION: Fat mass calculated with the new formula is independently associated with subclinical atherosclerosis in overweight/obese children.

Acid-base balance, serum electrolytes and need for non-invasive ventilation in patients with hypercapnic acute exacerbation of chronic obstructive pulmonary disease admitted to an internal medicine ward.

BACKGROUND: Hypoventilation produces or worsens respiratory acidosis in patients with hypercapnia due to acute exacerbations of chronic obstructive pulmonary disease (AECOPD). In these patients acid-base and hydroelectrolite balance are closely related. Aim of the present study was to evaluate acid-base and hydroelectrolite alterations in these subjects and the effect of non-invasive ventilation and pharmacological treatment. METHODS: We retrospectively analysed 110 patients consecutively admitted to the Internal Medicine ward of Cava de' Tirreni Hospital for acute exacerbation of hypercapnic chronic obstructive pulmonary disease. On admission all patients received oxygen with a Venturi mask to maintain arterial oxygen saturation at least >90 %, and received appropriate pharmacological treatment. Non-Invasive Ventilation (NIV) was started when, despite optimal therapy, patients had severe dyspnea, increased work of breathing and respiratory acidosis. Based on Arterial Blood Gas (ABG) data, we divided the 110 patients in 3 groups: A = 51 patients with compensated respiratory acidosis; B = 36 patients with respiratory acidosis + metabolic alkalosis; and C = 23 patients with respiratory acidosis + metabolic acidosis. 55 patients received only conventional therapy and 55 had conventional therapy plus NIV. RESULTS: The use of NIV support was lower in the patients belonging to group B than in those belonging to group A and C (25 %, vs 47 % and 96 % respectively; p < 0.01). A statistically significant association was found between pCO2 values and serum chloride concentrations both in the entire cohort and in the three separate groups. CONCLUSIONS: Our study shows that in hypercapnic respiratory acidosis due to AECOPD, differently from previous studies, the metabolic alkalosis is not a negative prognostic factor neither determines greater NIV support need, whereas the metabolic acidosis in addition to respiratory acidosis is an unfavourable element, since it determines an increased need of NIV and invasive mechanical ventilation support.

C-reactive protein and carotid intima-media thickness in children with sleep disordered breathing.

STUDY OBJECTIVES: Obesity is a risk factor for sleep disordered breathing (SDB) in children. Plasma levels of high-sensitivity C-reactive protein (Hs-CRP) are predictive of cardiovascular morbidity in adults, and CRP levels are associated with over-weight. Increased carotid intima-media thickness (IMT) is associated with several cardiovascular risk factors. We evaluated the effect of SDB on CRP levels and IMT in lean and obese children not selected for snoring. METHODS: 101 children (age 5-15 years) attending a weight clinic or scheduled for routine visit. IMT was measured with quantitative B-mode ultrasound scans. The apnea-hypopnea index (AHI) was measured overnight: AHI < 1 defined controls, AHI ≥ 1 to < 5 = mild SDB, and AHI ≥ 5 = obstructive sleep apnea (OSA). RESULTS: AHI was significantly associated with Hs-CRP concentration (r = 0.32, p = 0.002) in all 101 children irrespective of age and sex. Body mass index (BMI) was higher in OSA children than controls (25.5 ± 7.0 vs 22.1 ± 6.9, p = 0.05). Obese children had 3.3 times more probability of having OSA (HR 3.3, 95% CI 1.2-9.3, p = 0.02) than lean children. Hs-CRP values were significantly higher in children with OSA than in children without (p = 0.011), but not when BMI z-score was added as covariate. IMT was not associated with AHI or SDB. CONCLUSIONS: The results of this study suggest an association between OSA and Hs-CRP concentrations (mainly mediated by overweight and obesity), but not between OSA and subclinical atherosclerosis. There is scope for prevention in childhood before OSA syndrome causes the irreversible damage to arteries observed in adult patients.

Air pollution and carotid arterial stiffness in children.

BACKGROUND AND PURPOSE: Many studies unequivocally indicate that air pollution is directly linked to the adverse cardiovascular outcomes in the general population. No data are currently available on cardiovascular effects of exposure to trafficked roads in healthy children. Distance of the residence to a major road has been shown to be a useful proxy for long-term traffic exposure and seem to be more consistently associated with atherosclerosis than particulate matter 2.5. The aim of this study was to investigate a possible association between the distance to a major road and carotid arterial subclinical markers of atherosclerosis in a group of children in Italy. METHODS: The participants consisted of 52 healthy children living in a small town of the Amalphitan Coast with only one highly trafficked road. All children underwent an ultrasound carotid arterial examination. RESULTS: A statistically significant difference was found in carotid arterial stiffness between children living closer to the main street and other children, both those living between 330 and 730 metres from the main street and those living more than 750 metres from the main street. No significant differences were detectable in carotid arterial thickness and arterial blood pressure among the three groups of children. CONCLUSION: This study provides evidence in support of an association of exposure to air pollution with early atherosclerotic markers in healthy children. Impaired vascular health in childhood and adolescence gives further substance to the hypothesis that traffic exhausts are relevant to cardiovascular diseases even early in life.

Carotid artery stiffness in obese children with the metabolic syndrome.

Obesity and overweight have been associated with increased carotid intima-media thickness and stiffness in adults and children. Overweight and obesity have also been associated with an increased prevalence of the metabolic syndrome (MS). The aim of the study was to test the hypothesis that obese children with the MS have increased rigidity of their arteries compared with obese children without the MS. We studied 100 obese children (age range 6 to 14 years; 61 males, 39 females) consecutively seen in the outpatient clinic of a hospital department of pediatrics. Anthropometric measures and biochemical tests were performed in all children. Quantitative B-mode ultrasound scans were used to measure intima-media thickness and diameters of the common carotid artery. Common carotid arterial stiffness was significantly higher in the group of obese children with the MS (n = 38) at 1.29 +/- 0.06 mm (values log transformed) versus 1.12 +/- 0.04 mm (p <0.03) compared with those without the MS (n = 62). These differences persisted even after adjustment for age, gender, and C-reactive protein. Obese children with the MS had significantly higher plasma concentrations of C-reactive protein (1.57 +/- 0.06 microg/L, values log transformed) compared with obese children without the MS (1.38 +/- 0.05 microg/L, p <0.03). In conclusion, obese children who met the diagnostic criteria for the MS had higher common carotid artery stiffness and higher C-reactive protein plasma concentrations than obese children without the MS.