Genetic susceptibility and body mass in childhood cancer survivors

Childhood cancer survivors are at increased risk of many long-term treatment-related sequel such as second cancers, cardiovascular disease, and pulmonary complications. Certain treatments seem to influence the risk of becoming overweight, obese, or underweight, and abnormal body mass index (BMI) is associated with increased morbidity and mortality. Because BMI is modifiable, it is important to identify treatment and patient-related factors contributing to altered BMI. New research areas include exploring how genetic susceptibility through population polymorphism may contribute to BMI. Illuminating potential gene-environment interactions that influence obesity and underweight might be more readily accomplished in a study of high-risk individuals (i.e., childhood cancer survivors) with well-characterized exposures. The new Childhood Cancer Research Network in the Children's Oncology Group, when fully implemented, should make it less difficult in the future to recruit the large numbers of patients needed for such studies.     

Obesity and associated cardiovascular risk factors in Iranian children: A cross-sectional study

BACKGROUND: Obesity is a growing public health problem in developing countries considering its association with cardiovascular risk factors. Relationship between childhood obesity and these risk factors has not been attested in the Iranian population before. The aim of the present study was to investigate frequency of cardiovascular risk factors and their association with severity of obesity in a sample of Iranian obese children. METHODS: A total of 13 086 children aged 7-12 years were screened and those with waist circumference = 90th percentile of their age were invited for further evaluations. Participants were divided into two groups of overweight or obese according to International Obesity Task Force criteria. Cardiovascular risk factors were defined as high fasting total cholesterol, high low density lipoprotein, low high density lipoprotein, high triglycerides, and systolic or diastolic hypertension. These factors were compared between obese and overweight children and their correlations with body mass index and other measures of obesity were tested. RESULTS: Of 532 children (274 boys, mean age 9.5 +/- 1.3) enrolled in the study, 194 were overweight and 338 were obese. Mean levels of triglyceride and Apo-lipoprotein B in obese children were significantly higher than overweight participants. A total of 81.9% of obese children and 75.4% of overweight children had at least one cardiovascular risk factor. There were significant correlations between body mass index and systolic blood pressure, diastolic blood pressure, serum triglyceride, and Apo-lipoprotein B levels (P values <0.01). CONCLUSION: The high prevalence of cardiovascular risk factors in overweight and obese children and positive correlation of these factors with severity of obesity emphasizes the need for prevention and control of childhood obesity from early stages.     

Obesity, metabolic syndrome, and cardiovascular disease

Early childhood overweight and obesity have alarmingly increased over the years. Adulthood obesity is a well demonstrated significant independent predictor of cardiovascular risk (CVR) and/or mortality, which predisposes to the major components of metabolic syndrome (MS). Evidence of MS in obese children has been also reported associated with biochemical and inflammatory factors that affect vascular physiologic function. Assessment of vascular function can be measured noninvasively in children allowing early detection of endothelial dysfunction and severe increase of arterial stiffness before clinical manifestations of atherosclerosis. Impairment of endothelial function related to the severity of obesity and to the degree of insulin resistance is considered as a condition that confers a premature atherogenicity status and is linked to adult conventional cardiovascular risk factors. Adipose tissue factors that interfere with insulin action and endothelial cell function have also been identified as major precursors of CVR factors. The metabolic and cardiovascular consequences of childhood obesity are well demonstrated and have a major impact on the development of atherosclerosis and lifetime CVR. The development of programs involving both diet and exercise for children with overt overweight/obesity appears to be essential to improve vascular function and metabolic disorders. Such interventions should be complemented by a primary prevention against childhood obesity.     

Risk profiles for overweight/obesity among preschoolers

Background

The epidemic of overweight/obesity among U.S. children has led to an alarming increase in health-related consequences, including early-onset diabetes and cardiovascular disease. Recent research has identified the independent contribution of several maternal and child factors to the development of childhood overweight/obesity. Few studies, however, have examined risk profiles of childhood obesity.

Aim

This study used classification and regression tree (CART) analysis to examine the combined effect of maternal and child factors in generating risk profiles for overweight/obesity among preschoolers.

Study design

Data from the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B) study were used. The sample was comprised of preschool children. CART and logistic regression models were built and compared.

Results

Children who were overweight/obese at two years of age had an increased risk of being overweight/obese at four years of age. Children born to overweight/obese mothers were more likely to be overweight/obese by age four, even if their BMI at two years of age was normal. Children with high birth weight (≥ 4000 g.) were also more likely to be overweight/obese at age four years if they were born to mothers with a normal pregravid BMI, but were of a lower socioeconomic status. Among preschoolers whose mothers were black or white and who had a high pregravid BMI, breastfeeding duration and parity played an important role in determining their risk of being overweight/obese.

Conclusions

Classification tree analysis confirms and extends current knowledge of preschool overweight/obesity by providing preliminary risk profiles that are structured within the context of prenatal and postnatal maternal and child characteristics.     

Ethnic issues in the epidemiology of childhood obesity

Childhood obesity may be seen as a marker for high-risk dietary and physical inactivity practices. Recent increases in the prevalence of overweight and obesity among American children are not limited to one age, gender, or ethnic group, which suggests that unique behaviors of the members of various racial or ethnic subgroups of the population are unlikely to be the major contributing factors. Rather, it seems that environmental changes promoting increased energy intake and decreased energy output are occurring and have widespread impact on children from various backgrounds. Although no ethnic group is immune from the current shift in energy balance, differential rates of overweight seem to exist among ethnic groups. National probability samples of African-American, Hispanic, and white children in the United States provide clear evidence that white children are at lower risk for childhood overweight than are African-American or Hispanic children. Of concern is the lack of national data on the prevalence of overweight and obesity for Native-American and Asian-American groups. Also of concern is the aggregation of racial and ethnic subgroups, which may render prevalence rates meaningless. This possibility is clearly true with some surveys of weight status that combine diverse populations, such as Asians and Pacific Islanders, into one group. The high rates of obesity in African-American, Hispanic, and Native-American children are of concern. Although parental SES is associated inversely with childhood obesity among whites, higher SES does not seem to protect African-American and Hispanic children against obesity. In these groups, childhood obesity does not seem to be associated significantly with parental income and education. Health consequences of childhood obesity include a higher prevalence of type 2 diabetes and an increased risk for adverse levels of lipids, lipoproteins, and blood pressure. The effects of recently reported unprecedented levels of childhood overweight on subsequent risk for obesity in middle age are not known until future longitudinal data can be collected. It seems likely, however, that future health consequences of current early and severe childhood obesity will be staggering. Funding for adult follow-up of longitudinal studies of high-risk African American, Hispanic, and Native-American children is needed urgently to provide information on the long-term effects of childhood obesity. Halting the obesity epidemic is a formidable task, but the success in recent decades of drastically reducing childhood undernutrition offers hope and should spur similar action and leadership efforts. Promotion of efforts to reduce excess caloric intake with efforts to increase energy expenditure should receive paramount attention in the design of health programs. Given the relatively few published obesity-prevention and treatment studies that are designed to address specific cultural issues, it is important to promote the development of culturally appropriate intervention strategies that are shown to be effective among youth of diverse backgrounds. Although the dietary and activity goals will be similar, parental, family, and community messages and techniques grounded in cultural traditions and norms will be different for each ethnic group. This approach is crucial in the United States, a country with an increasingly diverse population.     

Sleep and obesity in children and adolescents

The purpose of this review is to provide a comprehensive update of epidemiologic studies that have assessed the association between sleep and obesity risk. Data suggest that short sleep is associated with an increased risk for being or becoming overweight/obese or having increased body fat. Late bedtimes are also a risk factor for overweight/obesity. Findings also suggest that changes in eating pathways may lead to increased body fat. Future experimental studies are needed to enhance our understanding of the underlying mechanisms through which sleep may play a role in the development and maintenance of childhood obesity.     

Significance of gender of obese children and body weight of parents and siblings for the results of the treatment of obesity in childhood

We studied the influence of family size, family history of obesity, and the obese children's sex on the short and medium term outcome of an obesity therapy in children aged 10.7 +/- 3 years with mean percentage overweight of 41.4 +/- 16.9%. Family parameters such as obesity on other family members, single child families, and sex of the obese children did not influence the decision to stop or to complete therapy. Boys were more successful in weight reduction than girls both after 3-6 months and after 3-5 years; the difference being not significant, however. Children without family history initially were significantly less overweight than those with familial obesity, and they exhibited the best short and medium term results. Children of obese families initially were the fattest ones. They reduced their weight more than average, but they tended to regain weight during the following 3-5 years, reaching the highest levels of overweight after that time. Children without family history of obesity did not regain weight, however. Thus even after good short term results obese children of obese parents should be regarded at risk for relapse and should be checked for years after therapy to prevent weight regain.     

Childhood obesity

Several conclusions can be drawn on the basis of the research reviewed: Obese children are more likely to become obese adults than are their thinner peers. Parent weight may interact with child weight status in the etiology of adult obesity. Obese children with obese parents are more likely to become obese adults than are obese children with thin parents. The prediction of adult obesity from childhood obesity improves with the age of the child. As the obese child gets older, he or she is more likely to become an obese adult. The inclusion of parents in the treatment process is important for the success of childhood weight control. It may be best to see the parent and child separately in treatment meetings rather than together. Children with thin parents may do better in weight control than children of obese parents. Adherence to exercise is likely to be a problem with obese children, and the choice or design of an exercise program should take these adherence problems into account. Nutritional adequacy of the child's diet should be evaluated both in terms of what the child is eating as well as in terms of the prescribed diet. Likewise, growth of the obese child during dieting should be monitored and should be related to expected height, which can be based on parent height. In summary, childhood obesity is a problem that places a child at great risk for becoming an obese adult. However, a growing body of research has emerged that has identified important risk factors for the development of obesity in children. Likewise, treatment methods have been developed that produce significant and long-lasting effects on childhood weight status. Continued development of treatment methods would be of great potential importance in the prevention and treatment of this prevalent problem.     

Family environmental factors influencing the developing behavioral controls of food intake and childhood overweight

Although a large body of research has assessed direct genetic links between parent and child weight status, relatively little research has assessed the extent to which parents (particularly parents who are overweight) select environments that promote overweight among their children. Parents provide food environments for their children's early experiences with food and eating. These family eating environments include parents' own eating behaviors and child-feeding practices. Results of the limited research on behavioral mediators of familial patterns of overweight indicate that parents' own eating behaviors and their parenting practices influence the development of children's eating behaviors, mediating familial patterns of overweight. In particular, parents who are overweight, who have problems controlling their own food intake, or who are concerned about their children's risk for overweight may adopt controlling child-feeding practices in an attempt to prevent overweight in their children. Unfortunately, research reveals that these parental control attempts may interact with genetic predispositions to promote the development of problematic eating styles and childhood overweight. Although the authors have argued that behavioral mediators of family resemblances in weight status, such as parents' disinhibited or binge eating and parenting practices are shaped largely by environmental factors, individual differences in these behaviors also have genetic bases. A primary public health goal should be the development of family-based prevention programs for childhood overweight. The findings reviewed here suggest that effective prevention programs must focus on providing anticipatory guidance on parenting to foster patterns of preference and food selection in children more consistent with healthy diets and promote children's ability to self-regulate intake. Guidance for parents should include information on how children develop patterns of food intake in the family context. Practical advice for parents includes how to foster children's preferences for healthy foods and how to promote acceptance of new foods by children. Parents need to understand the costs of coercive feeding practices and be given alternatives to restricting food and pressuring children to eat. Providing parents with easy-to-use information regarding appropriate portion sizes for children is also essential as are suggestions on the timing and frequency of meals and snacks. Especially during early and middle childhood, family environments are the key contents for the development of food preferences, patterns of food intake, eating styles, and the development of activity preferences and patterns that shape children's developing weight status. Designing effective prevention programs will, however, require more complete knowledge than currently available regarding behavioral intermediaries that foster overweight, including the family factors that shape activity patterns, meals taken away from home, the impact of stress on family members' eating styles, food intake, activity patterns, and weight gain. The research presented here provides an example of how ideas regarding the effects of environmental factors and behavioral mediators on childhood overweight can be investigated. Such research requires the development of reliable and valid measures of environmental variables and behaviors. Because childhood overweight is a multifactorial problem, additional research is needed to develop and test theoretic models describing how a wide range of environmental factors and behavioral intermediaries can work in concert with genetic predispositions to promote the development of childhood overweight. The crucial test of these theoretic models will be in preventive interventions.     

Low and high birth weight as risk factors for obesity among 4 to 5-year-old Australian children: does gender matter?

Studies testing whether birth weight and childhood obesity differ by gender are lacking. We aimed to describe the relationship between birth weight and childhood overweight/obesity and investigate the influence that gender has on this relationship among 4 to 5-year-old children. We performed a secondary analysis of an Australian nationally representative cross-sectional study in 4 to 5-year-old children. The main outcome measure was child overweight and obesity. We found that low birth weight (LBW) was associated with lower risk of overweight/obesity among girls at 4–5 years before (OR 0.50, 95%CI 0.32, 0.77) and after adjusting for socio-demographic factors (OR 0.51 95% CI 0.33, 0.80) and ethnicity (OR 0.52, 95%CI 0.33, 0.81) but was not associated with child overweight/obesity among boys before or after adjustment. High birth weight (HBW) was associated with a higher risk of overweight/obesity among both girls (adjusted OR: 1.76, 95%CI 1.12, 2.78) and boys (adjusted OR: 2.42 95% CI 2.06, 2.86). Conclusion: There are gender differences in the association of birth weight with child overweight/obesity. HBW was associated with a higher risk of child overweight/obesity in boys and girls before and after adjustment for socio-demographic factors. However, LBW was associated with a lower risk of child overweight/obesity in girls but not in boys. These gender differences need to be considered when planning interventions to reduce child overweight/obesity.     

Das metabolische Syndrom

The metabolic syndrome (MetS) is defined by coincidence of the risk factors visceral obesity, hypertension, dyslipidaemia, insulin resistance and possibly disturbed glucose regulation. MetS is the driving force for the development of cardiovascular diseases and adult-onset diabetes already in childhood. There is a clear genetic predisposition. The symptoms are aggravated by energy-dense food and physical inactivity. Central pathogenetic findings associated with the MetS are insulin resistance in different cell systems as well as chronic inflammation of the fat tissue. The prevalence of the MetS in industrial nations is about 0.1%/5?C8%/20?C35% in normal-weight/overweight/obese children and adolescents. There is no causal therapy of the MetS. A therapeutic approach is the modification of the nutrition and exercise behaviour. The medical therapy directly aims at the treatment of the individual risk factors. Behaviour-based preventive measures in day care and schools with involvement of the parents can contribute to the prevention of the MetS.     

Risk factors for childhood overweight: a prospective study from birth to 9.5 years

OBJECTIVES: To ascertain risk factors for the development of overweight in children at 9.5 years of age. STUDY DESIGN: This was a prospective study of 150 children from birth to 9.5 years of age, with assessment of multiple hypothesized risk factors drawn from research reports. RESULTS: Five independent risk factors for childhood overweight were found. The strongest was parent overweight, which was mediated by child temperament. The remaining risk factors were low parent concerns about their child's thinness, persistent child tantrums over food, and less sleep time in childhood. Possible mechanisms by which each of these factors influence weight gain are outlined. Two different pathways to childhood overweight/obesity were found, depending on degree of parental overweight. CONCLUSIONS: There is evidence of considerable interaction between parent and child characteristics in the development of overweight. Several of the identified risk factors are amenable to intervention possibly leading to the development of early prevention programs.     

Cesarean section and the risk of overweight in grade 6 children

We examined the relationship between cesarean section (C-section) and the risk of overweight and obesity in children in grade 6 (mean age, 11.92 years; standard deviation?=?0.34). Data from phase I through phase III of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development were used. Children with complete data from 1991 through 2004 were included in this study (n?=?917). Multiple logistic regression analyses were used to adjust for potential confounding and to evaluate the association of C-section and childhood overweight and obesity. Compared to children delivered vaginally, children delivered by C-section had approximately twice the likelihood of being overweight (odds ratio (OR)?=?1.86, 95 % confidence interval (CI)?=?1.27–2.73) or obese (OR?=?1.87, 95 % CI?=?1.19–2.95). However, when examined according to sex, males delivered by C-section had an increased risk for being overweight (OR?=?1.78, 95 % CI?=?1.01–3.12) and obese (OR?=?2.58, 95 % CI?=?1.36–4.88), while females had an increased risk only for being overweight (OR?=?1.99, 95 % CI?=?1.17–3.39). Conclusion: C-section was associated with an increased risk of overweight and obesity in children in grade 6, but the relationship differed according to gender. Further longitudinal studies are warranted to examine the long-term effect of delivery mode on the risk of childhood overweight.     

Increasing incidence of childhood obesity

Childhood obesity is a nutritional, metabolic and endocrine disease; all of these factors have genetic components. Attractive for writers and painters, it has been found to be a medical risk. Childhood obesity had been neglected until about 30 years ago. A series of cross-sectional and longitudinal studies performed in many countries using mainly BMI values as determinant of overweight have shown that there is an overall fast rise in overweight in many populations, usually starting around age 7. In certain populations and ethnic groups the rise and degree of obesity are especially high, such as the Hispano-Black and Native Americans and European countries. School children in the US, Greece, Ireland and Portugal are more overweight than those in 12 other countries. In addition to genetic factors, rapid changes in life style (more energy intake and less energy output) are the major factors causing childhood obesity. In recent years it has been recognized as a fast increasing public health problem.     

Clinical practice

Childhood obesity has reached epidemic proportions in many parts of the world. This epidemic has also affected children and adults with congenital heart disease (CHD). Over one quarter of children with CHD are overweight or obese. Important comorbidities are associated with obesity including type 2 diabetes, systemic hypertension, hyperlipidemia, and obstructive sleep apnea. Obese children with CHD often have the traditional risk factors such as genetic predisposition, sedentary lifestyle, and poor dietary habits. However, they may also have unique risk factors such as higher caloric needs in early infancy and exercise restriction in childhood. Similar to children with normal hearts, those with CHD have higher left ventricular mass and abnormal vascular function and are more likely to have systemic hypertension. In the long term, these comorbidities may have a more profound effect on children who have underlying functional and/or anatomical abnormalities of the heart. As more children with CHD are now surviving into adulthood, investigating therapeutic interventions to treat and prevent obesity in this population is of utmost importance. Recommendations for safe physical activity, recreation sport, and exercise training for children with CHD have recently been published. These guidelines may help health care providers to change their practice of exercise restriction.     

Risk factors for childhood overweight

PURPOSE OF REVIEW: We review the 2004 literature on risk factors for childhood overweight. Given the steady increase in the prevalence of childhood overweight, the identification of risk factors is of increasing importance. RECENT FINDINGS: A number of studies confirmed that parental overweight is the most potent risk factor for childhood overweight. Childhood temperament was found to mediate the effects of parental overweight with a difficult temperament increasing the risk of overweight. Newer findings implicate regular consumption of fast food and sweetened drinks as risk factors, as well as sedentary behavior; although a meta-analysis suggested that the effects of the latter factor are small. Other work was consistent with the finding that parental overcontrol of children's feeding behavior, particularly for those at high risk of developing overweight, may lead to overweight. SUMMARY: Identification of groups of children at high risk for becoming overweight offers the potential for early intervention to reduce the intergenerational transfer of obesity. This is an area for future research because the nature of effective intervention is at present unclear. There is a suggestion that focused behavior change efforts on one target such as reducing the intake of sweetened beverages may be more successful than attempts to make broader dietary changes. There is also evidence that targeting parental behaviors may be more effective than interventions directed solely toward children, suggesting that modification of the environment that a child is exposed to during early development may have a lasting effect.     

Metabolic syndrome in childhood

The World Health Organization has described obesity as the world epidemic of the twentieth century, ranking as the main problem in public health. In Spain, the enKid study, undertaken in a population aged between 2 and 24 years, shows prevalences of 13.9 % for obesity and 12.4 % for overweight. Longitudinal studies suggest that childhood obesity after the age of 3 years correlates with a greater risk of obesity in adulthood, with an increase in morbility and mortality due to the persistence of associated metabolic disorders. Among these disorders is the metabolic syndrome, defined as the association of several risk factors that herald arteriosclerotic cardiovascular disease and type 2 diabetes in adulthood, with insulin resistance playing a major role in its pathophysiology. Despite its importance, there is still no universally accepted pediatric definition of this syndrome, hampering exact knowledge of its scope, although the prevalence observed in numerous studies performed in obese pediatric patients ranges from 20-30 %.     

When is family history obtained? – Lack of timely documentation of family history among overweight and hypertensive paediatric patients

Aim: Taking a detailed family history is an inexpensive way for healthcare providers to screen patients for increased risk of various chronic conditions. Documentation of family history, however, has been shown to be incomplete in the majority of patient charts. The current study examines when family history is collected within the context of the development and diagnosis of chronic conditions in paediatrics, using hypertension and overweight/obesity as examples. Methods: We analysed family history data from the electronic medical records of 5485 overweight/obese and 774 hypertensive children and adolescents in a large, urban medical system in northeast Ohio. Manual review of 200 charts was also performed. Results: Family history information was entered prior to the development of hypertension in 13.5% of hypertensive patients with a family history of hypertension, and it was entered prior to the development of abnormal weight in 35.5% of overweight/obese patients with a family history of obesity or a related condition. Of patients with a relevant family history who received an actual diagnosis for either of these conditions, only 16.7% of hypertensive and 33.3% of overweight/obese patients had this family history documented prior to diagnosis. Conclusions: These results imply that paediatric providers may not use family history as a screening tool for assessing future risk of obesity and hypertension, but instead gather this information after these chronic conditions have developed, making it difficult to implement preventative or screening strategies based on familial risk.     

The consequences of childhood overweight and obesity

Researchers are only gradually becoming aware of the gravity of the risk that overweight and obesity pose for children's health. In this article Stephen Daniels documents the heavy toll that the obesity epidemic is taking on the health of the nation's children. He discusses both the immediate risks associated with childhood obesity and the longer-term risk that obese children and adolescents will become obese adults and suffer other health problems as a result. Daniels notes that many obesity-related health conditions once thought applicable only to adults are now being seen in children and with increasing frequency. Examples include high blood pressure, early symptoms of hardening of the arteries, type 2 diabetes, nonalcoholic fatty liver disease, polycystic ovary disorder, and disordered breathing during sleep. He systematically surveys the body's systems, showing how obesity in adulthood can damage each and how childhood obesity exacerbates the damage. He explains that obesity can harm the cardiovascular system and that being overweight during childhood can accelerate the development of heart disease. The processes that lead to a heart attack or stroke start in childhood and often take decades to progress to the point of overt disease. Obesity in childhood, adolescence, and young adulthood may accelerate these processes. Daniels shows how much the same generalization applies to other obesity-related disorders-metabolic, digestive, respiratory, skeletal, and psychosocial-that are appearing in children either for the first time or with greater severity or prevalence. Daniels notes that the possibility has even been raised that the increasing prevalence and severity of childhood obesity may reverse the modern era's steady increase in life expectancy, with today's youth on average living less healthy and ultimately shorter lives than their parents-the first such reversal in lifespan in modern history. Such a possibility, he concludes, makes obesity in children an issue of utmost public health concern.     

Association of energy intake and expenditure with obesity: A cross-sectional study of 150 pediatric patients following treatment for leukemia

Increased obesity in leukemia survivors has been attributed to chemotherapy and radiation. Data on total energy intake (TEI) and total energy expenditure (TEE) are lacking in obese childhood leukemia patients after completion of therapy from India. We conducted a cross-sectional study in pediatric acute leukemia patients after completion of therapy wherein energy intake was assessed by 24-hour recall method. TEE was calculated using Harris–Benedict equation, by assessing the physical activity level using Physical Activity Questionnaire for children and basal metabolic rate by World Health Organization equation. Indian Academy of Pediatrics 2015 guidelines for BMI were used for defining overweight and obesity. Nutritional status was assessed in 150 leukemia patients after completion of therapy. Twenty-five percent of leukemia patients after completion of therapy were overweight and obese versus 11% of healthy controls (p = 0.042). The mean ratio of TEI/required energy intake (REI), TEE/required energy expenditure (REE), and (TEI:REI)/(TEE:REE) were significantly higher in overweight and obese group versus nonobese survivors (p < 0.001, p = 0.091, p < 0.001, respectively). Multivariate analysis showed higher income (HR-2.3, p = 0.04), increased TEI/REI (HR-4, p = 0.049) and higher (TEI:REI)/(TEE:REE) (HR-3.1, p = 0.039) to be significant factors predicting obesity. Obesity in leukemia patients after completion of therapy is associated with increased energy intake, causing imbalance between energy intake and TEE in these patients.