Kevin C. Harris

Effect of school-based physical activity interventions on body mass index in children: a meta-analysis

Background: The prevalence of childhood obesity is increasing at an alarming rate. Many local governments have enacted policies to increase physical activity in schools as a way to combat childhood obesity. We conducted a systematic review and meta-analysis to determine the effect of school-based physical activity interventions on body mass index (BMI) in children. Methods: We searched MEDLINE, EMBASE, CINAHL and the Cochrane Central Register of Controlled Trials up to September 2008. We also hand-searched relevant journals and article reference lists. We included randomized controlled trials and controlled clinical trials that had objective data for BMI from before and after the intervention, that involved school-based physical activity interventions and that lasted for a minimum of 6 months. Results: Of 398 potentially relevant articles that we identified, 18 studies involving 18 141 children met the inclusion criteria. The participants were primarily elementary school children. The study duration ranged from 6 months to 3 years. In 15 of these 18 studies, there was some type of co-intervention. Meta-analysis showed that BMI did not improve with physical activity interventions (weighted mean difference –0.05 kg/m2, 95% confidence interval –0.19 to 0.10). We found no consistent changes in other measures of body composition. Interpretation: School-based physical activity interventions did not improve BMI, although they had other beneficial health effects. Current population-based policies that mandate increased physical activity in schools are unlikely to have a significant effect on the increasing prevalence of childhood obesity.

Childhood Obesity and Cardiovascular Dysfunction

Obesity-related cardiovascular disease in children is becoming more prevalent in conjunction with the rise in childhood obesity. Children with obesity are predisposed to an increased risk of cardiovascular morbidity and mortality in adulthood. Importantly, research in children with obesity over the last decade has demonstrated that children may exhibit early signs of cardiovascular dysfunction as a result of their excess adiposity, often independent of other obesity-related comorbidities such as dyslipidemia and insulin resistance. The clinical evidence is accumulating to suggest that the cardiovascular damage, once observed only in adults, is also occurring in obese children. The objective of this review is to provide a synopsis of the current research on cardiovascular abnormalities in children with obesity and highlight the importance and need for early detection and prevention programs to mitigate this potentially serious health problem.

Should early extubation be the goal for children after congenital cardiac surgery

OBJECTIVE We sought to determine the feasibility and assess the clinical outcomes associated with an early extubation strategy for all children undergoing congenital heart surgery, including neonates (age, <30 days). METHODS We performed a linked database analysis of all patients undergoing congenital heart surgery from July 1, 2010 to December 31, 2012. We collected data on the cardiac diagnoses, preoperative status, procedure, and postoperative course, including the duration of invasive and noninvasive ventilation, failure of extubation, hemodynamic data, length of stay, complications, and mortality. A multivariable model was used to assess the independent factors associated with an inability to extubate within the operating room and with delayed extubation (>24 hours). RESULTS We operated on 613 children, including 97 neonates. Intraoperative extubation was achieved in 71% of the cases and early extubation (≤ 24 hours) was achieved in 89% of the cases. The overall mortality was 1.5% (9 of 613 patients). Early extubation was associated with lower mortality (1% vs 9%, P < .001) and a lower rate of reintubation (4% vs 23%, P < .001) compared with delayed extubation. Notably, 63% of the neonates were extubated within 24 hours, including 67% of arterial switch operations and 54% of total anomalous pulmonary venous return repairs. Norwood operations were the only procedure in which no patient was extubated within the first 24 hours. Multivariable logistic regression demonstrated that the predictors of delayed extubation included preoperative mechanical ventilation, weight < 5 kg, a longer procedure time, and the need for postoperative inotrope support. Implementation of an early extubation strategy was associated with low rates of complications (5.1 per 10 procedures), short lengths of intensive care unit stay (median, 1 day; interquartile range, 1-3), and short hospital stays (median, 4 days; interquartile range, 3-6). CONCLUSIONS Most children undergoing congenital heart surgery can be extubated in the operating room. Most neonates, including many undergoing complex procedures, can be extubated within the first 24 hours after surgery. Early extubation was associated with low morbidity rates and short lengths of intensive care unit and hospital stays.

Single-ventricle anatomy predicts delayed microstructural brain development

Background:Term newborns with congenital heart disease (CHD) show delayed brain development as early as the third trimester, especially in single-ventricle physiology (SVP). Mechanisms causing delayed brain development in CHD are uncertain but may include impaired fetal brain blood flow. Our objective was to determine if cardiac anatomy associated with obstruction to antegrade flow in the ascending aorta is predictive of delayed brain development as measured by diffusion tensor imaging and magnetic resonance spectroscopic (MRS) imaging.Methods:Echocardiograms from 36 term newborns with SVP were reviewed for the presence of aortic atresia and the diameter of the ascending aorta. Quantitative magnetic resonance imaging parameters measuring brain microstructural (fractional anisotropy (FA) and average diffusivity (Dav)) or metabolic development (N-acetylaspartate (NAA) and lactate/choline (Lac/Cho)) were recorded.Results:Increasing NAA/Cho and white matter (WM) FA, and decreasing Dav and Lac/Cho characterize normal brain development. Consistent with the hypothesis that delayed brain development is related to impaired brain perfusion, smaller ascending aortic diameter and aortic atresia were associated with higher Dav and lower WM FA. Echocardiogram variables were not associated with brain metabolic measures.Conclusions:These observations support the hypothesis that obstruction to fetal cerebral blood flow impairs brain microstructural development.

Obesity and Arterial Stiffness in Children Systematic Review and Meta-Analysis

Objective— Childhood obesity is associated with risk factors for cardiovascular disease. Arterial stiffness is considered one of the earliest detectable measures of vascular damage. There is controversy in the literature regarding the effects of childhood obesity on arterial stiffness. The objective of this study is to systematically review the literature and to conduct a meta-analysis comparing measures of central arterial stiffness in children and adolescents with obesity to healthy body mass index controls. Approach and Results— Literature searches were conducted using databases (eg, MEDLINE, EMBASE) and citations cross-referenced. Studies assessing central pulse wave velocity or β-stiffness index were included. A random effects meta-analysis of the standardized mean difference and 95% confidence intervals in arterial stiffness between children with obesity and control children was performed for each arterial stiffness measure. A total of 523 studies were identified. Fifteen case–control studies were included, with 2237 children/adolescents (1281 with obesity, 956 healthy body mass index controls) between 5 and 24 years of age. All studies measuring carotid and aortic β-stiffness index and 10/12 studies measuring central pulse wave velocity reported greater arterial stiffness in children/adolescents with obesity compared with controls. A random effects meta-analysis was performed revealing a significant effect of obesity on pulse wave velocity (standardized mean difference=0.718; 95% confidence interval=0.291–1.415), carotid β-stiffness index (0.862; 0.323–1.402), and aortic β stiffness index (1.017; 0.419–1.615). Conclusion— These findings indicate that child/adolescent obesity is associated with greater arterial stiffness. However, further research is needed to address confounders, such as pubertal status, that may affect this relationship in children. In the future, these techniques may be useful in risk stratification and guiding clinical management of obese children to optimize cardiovascular outcomes. # Significance {#article-title-50}Objective— Childhood obesity is associated with risk factors for cardiovascular disease. Arterial stiffness is considered one of the earliest detectable measures of vascular damage. There is controversy in the literature regarding the effects of childhood obesity on arterial stiffness. The objective of this study is to systematically review the literature and to conduct a meta-analysis comparing measures of central arterial stiffness in children and adolescents with obesity to healthy body mass index controls. Approach and Results— Literature searches were conducted using databases (eg, MEDLINE, EMBASE) and citations cross-referenced. Studies assessing central pulse wave velocity or &bgr;-stiffness index were included. A random effects meta-analysis of the standardized mean difference and 95% confidence intervals in arterial stiffness between children with obesity and control children was performed for each arterial stiffness measure. A total of 523 studies were identified. Fifteen case–control studies were included, with 2237 children/adolescents (1281 with obesity, 956 healthy body mass index controls) between 5 and 24 years of age. All studies measuring carotid and aortic &bgr;-stiffness index and 10/12 studies measuring central pulse wave velocity reported greater arterial stiffness in children/adolescents with obesity compared with controls. A random effects meta-analysis was performed revealing a significant effect of obesity on pulse wave velocity (standardized mean difference=0.718; 95% confidence interval=0.291–1.415), carotid &bgr;-stiffness index (0.862; 0.323–1.402), and aortic &bgr; stiffness index (1.017; 0.419–1.615). Conclusion— These findings indicate that child/adolescent obesity is associated with greater arterial stiffness. However, further research is needed to address confounders, such as pubertal status, that may affect this relationship in children. In the future, these techniques may be useful in risk stratification and guiding clinical management of obese children to optimize cardiovascular outcomes.

Obesity and Arterial Stiffness in Children

Objective— Childhood obesity is associated with risk factors for cardiovascular disease. Arterial stiffness is considered one of the earliest detectable measures of vascular damage. There is controversy in the literature regarding the effects of childhood obesity on arterial stiffness. The objective of this study is to systematically review the literature and to conduct a meta-analysis comparing measures of central arterial stiffness in children and adolescents with obesity to healthy body mass index controls. Approach and Results— Literature searches were conducted using databases (eg, MEDLINE, EMBASE) and citations cross-referenced. Studies assessing central pulse wave velocity or β-stiffness index were included. A random effects meta-analysis of the standardized mean difference and 95% confidence intervals in arterial stiffness between children with obesity and control children was performed for each arterial stiffness measure. A total of 523 studies were identified. Fifteen case–control studies were included, with 2237 children/adolescents (1281 with obesity, 956 healthy body mass index controls) between 5 and 24 years of age. All studies measuring carotid and aortic β-stiffness index and 10/12 studies measuring central pulse wave velocity reported greater arterial stiffness in children/adolescents with obesity compared with controls. A random effects meta-analysis was performed revealing a significant effect of obesity on pulse wave velocity (standardized mean difference=0.718; 95% confidence interval=0.291–1.415), carotid β-stiffness index (0.862; 0.323–1.402), and aortic β stiffness index (1.017; 0.419–1.615). Conclusion— These findings indicate that child/adolescent obesity is associated with greater arterial stiffness. However, further research is needed to address confounders, such as pubertal status, that may affect this relationship in children. In the future, these techniques may be useful in risk stratification and guiding clinical management of obese children to optimize cardiovascular outcomes. # Significance {#article-title-50}Objective— Childhood obesity is associated with risk factors for cardiovascular disease. Arterial stiffness is considered one of the earliest detectable measures of vascular damage. There is controversy in the literature regarding the effects of childhood obesity on arterial stiffness. The objective of this study is to systematically review the literature and to conduct a meta-analysis comparing measures of central arterial stiffness in children and adolescents with obesity to healthy body mass index controls. Approach and Results— Literature searches were conducted using databases (eg, MEDLINE, EMBASE) and citations cross-referenced. Studies assessing central pulse wave velocity or &bgr;-stiffness index were included. A random effects meta-analysis of the standardized mean difference and 95% confidence intervals in arterial stiffness between children with obesity and control children was performed for each arterial stiffness measure. A total of 523 studies were identified. Fifteen case–control studies were included, with 2237 children/adolescents (1281 with obesity, 956 healthy body mass index controls) between 5 and 24 years of age. All studies measuring carotid and aortic &bgr;-stiffness index and 10/12 studies measuring central pulse wave velocity reported greater arterial stiffness in children/adolescents with obesity compared with controls. A random effects meta-analysis was performed revealing a significant effect of obesity on pulse wave velocity (standardized mean difference=0.718; 95% confidence interval=0.291–1.415), carotid &bgr;-stiffness index (0.862; 0.323–1.402), and aortic &bgr; stiffness index (1.017; 0.419–1.615). Conclusion— These findings indicate that child/adolescent obesity is associated with greater arterial stiffness. However, further research is needed to address confounders, such as pubertal status, that may affect this relationship in children. In the future, these techniques may be useful in risk stratification and guiding clinical management of obese children to optimize cardiovascular outcomes.

Feasibility of Optical Coherence Tomography in Children with Kawasaki Disease and Pediatric Heart Transplant Recipients

Background—Optical coherence tomography (OCT) is a high-resolution intravascular imaging technique used in adults. We tested the hypothesis that OCT could identify coronary abnormalities not seen by angiography in children with a history of Kawasaki disease (KD) and pediatric heart transplant (TX) recipients. Methods and Results—Patients with KD and TX recipients were evaluated between December 2012 and October 2013 with angiography and OCT (Ilumien System, LightLabs, St Jude Medical, Westford, MA). Modifications were made to the adult OCT protocol to adapt this technique for children. Serial cross-sectional area measurements of the lumen, intima, and media were made. Entire imaging data were analyzed for the presence of qualitative changes. Seventeen children were evaluated (5 patients with KD; 12 TX recipients). In patients with KD, angiography was normal. However, OCT imaging revealed that significant vessel wall abnormalities were present in all children including intimal thickening (intima/lumen cross-sectional area ratio>0.4), loss of the normal layered structure of the vessel wall, white thrombus, calcification, and neovascularization. There was extensive destruction of the internal elastic lamina. In TX recipients, angiography was normal; however, intimal thickening (intima/media cross-sectional area ratio>1) was seen in 9 of 12 patients. The median intima/media cross-sectional area ratio was 1.18. Conclusions—In this initial experience with OCT in children, we have identified significant coronary abnormalities with OCT that are angiographically silent in children with a history of coronary aneurysms because of KD and in pediatric TX recipients.

Economic Evaluation of Palivizumab in Children With Congenital Heart Disease: A Canadian Perspective

BACKGROUND Respiratory syncytial virus (RSV) is a common cause of bronchiolitis in infants. In children with congenital heart disease (CHD), it is associated with significant morbidity and mortality. Palivizumab is a monoclonal antibody that reduces the number of RSV-associated hospitalizations in children with CHD. We sought to assess cost savings and cost-effectiveness of palivizumab in children < 2 years old with hemodynamically significant CHD in a provincially administered RSV prophylaxis program. METHODS A cohort of children who received palivizumab (N = 292) from 2003-2007 was compared to a historical cohort of children (N = 412) from 1998-2003 who met the eligibility criteria for palivizumab prior to initiation of the prophylaxis program. Direct and indirect costs and benefits were determined. RESULTS The direct and indirect costs in the historical cohort were

Biophysical properties of the aorta and left ventricle and exercise capacity in obese children.

838 per patient season compared to

A prospective observational multicenter study of balloon angioplasty for the treatment of native and recurrent coarctation of the aorta.

9130 per patient season in the palivizumab cohort. Risk of admission was reduced by 42%, and days in hospital were reduced by 83%. The incremental cost of the RSV prophylaxis program was