Adapting the "Chester step test" to predict peak oxygen uptake in children.

Maximal exercise testing may be difficult to perform in clinical practice, especially in obese children who have low cardiorespiratory fitness and exercise tolerance. We aimed to elaborate a model predicting peak oxygen consumption (VO2) in lean and obese children with use of the submaximal Chester step test. We performed a maximal step test, which consisted of 2-minute stages with increasing intensity to exhaustion, in 169 lean and obese children (age range: 7-16 years). VO2 was measured with indirect calorimetry. A statistical Tobit model was used to predict VO2 from age, gender, body mass index (BMI) z-score and intensity levels. Estimated VO2peak was then determined from the heart rate-VO2 linear relationship extrapolated to maximal heart rate (220 minus age, in beats.min-1). VO2 (ml/kg/min) can be predicted using the following equation: VO2 = 22.82 - [0.68*BMI z-score] - [0.46*age (years)] - [0.93*gender (male = 0; female = 1)] + [4.07*intensity level (stage 1, 2, 3 etc.)] - [0.24*BMI z-score *intensity level] - [0.34*gender*intensity level]. VO2 was lower in participants with high BMI z-scores and in female subjects. The Chester step test can assess cardiorespiratory fitness in lean and obese children in clinical settings. Our adapted equation allows the Chester step test to be used to estimate peak aerobic capacity in children

Obesity and disease activity in juvenile idiopathic arthritis

<p>Abstract</p> <p>Background</p> <p>Children with physical disabilities may have an increased risk for obesity and obesity might be a risk factor for inflammatory arthritis. The aims of this study were: to determine the prevalence of obesity in children and adolescents with juvenile idiopathic arthritis (JIA), and to examine the association between obesity and disease activity in this population.</p> <p>Findings</p> <p>A cross-sectional analysis of all patients with JIA attending a pediatric rheumatology clinic, between October 2009 and September 2010, was performed. A linear regression model was used to explore the association between obesity and disease activity in patients with JIA. A total of 154 subjects were included in the analysis; median age was 10.6 years, 61% were female, and 88% were white. Obesity was found in 18%, 12% were overweight, and 3% were underweight. There was no association between obesity and JADAS-27 (Juvenile Arthritis Disease Activity Score 27), physician's assessment of disease activity, parent's assessment of child's well-being, erythrocyte sedimentation rate, number of active joints, or C-reactive protein (p-value range 0.10 to 0.95).</p> <p>Conclusions</p> <p>Although 18% of patients with JIA were obese, we did not find an association between obesity and disease activity. As obesity confers an additional health risk in children with arthritis, addressing this co-morbidity should be a health priority in patients with JIA. Future studies are necessary to further explore potential associations between obesity, development of JIA, and disease activity.</p

Serum cardiovascular risk biomarkers in pre-pubertal obese children.

Childhood obesity is associated with premature cardiovascular complications. However, little is known about the effect of a family-based behavioural intervention on the relationship between arterial function, blood pressure and biomarkers in pre-pubertal children with obesity. This was a single centre randomized controlled trial (RCT) including 74 children randomized to a 6-month behavioural intervention to treat obesity. In 48 children (13 controls and 35 interventions), we assessed: serum level of cytokine (CCL2), adiponectin, and neutrophil product (MMP-8), as well as carotid intima-media thickness, flow-mediated dilation (FMD), nitroglycerin-mediated dilation; arterial stiffness (incremental elastic modulus, Einc), pulse wave velocity (PWV), resting and 24-hour blood pressure (BP). At baseline, resting systolic BP was positively associated with MMP-8 levels which was significantly higher in children with hypertension (P = 0.033). Biochemical markers were not related to endothelial function at baseline, but they globally increased after 6 months in the intervention group. The significant increase of CCL2 levels in the intervention group was associated with a decrease in diastolic BP. Furthermore, adiponectin change was positively related to a change in FMD and negatively to change in Einc and PWV. The usefulness of serum biomarkers for the detection of cardiovascular diseases is not well established in children. In our population, MMP-8 concentration was higher in hypertensive children. Furthermore, behavioural interventions resulted in a paradoxical increase in some biomarkers in children, with potentially beneficial effects detected with CCL2 changes. Caution should be taken when using nonspecific serum biomarkers for the clinical monitoring of children with obesity

A 13-Year-Old Male With Diagnosed Idiopathic Pulmonary Hypertension: Is it Really Idiopathic?

A 13-year-old male was referred after incidental finding of cardiomegaly on chest radiograph and signs of pulmonary hypertension on subsequent cardiology consult. He was diagnosed with idiopathic pulmonary hypertension, and came to our center for a second opinion. He was born from consanguineous parents. He reported to be asymptomatic in his daily life. He was not on medications. Family history was not contributive