Porth's Essentials of Pathophysiology, 4e

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Disorders of Nutritional Status

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benefit of offering surgery to patients with even lower levels of obesity (e.g., BMI >30 with comorbid condi- tions such as diabetes). 34

Disease Control and Prevention (CDC) assembled an expert committee to develop recommendations for the assessment, prevention, and treatment of this public health problem. 37 Their recommendations include a yearly assessment of weight status in all children by mea- surement of height and weight to determine BMI for age and comparing it to standard growth charts. Children who are 2 to 18 years of age with a BMI greater than or equal to the 95th percentile for age and sex or a BMI greater than 30 (whichever is smaller) should be classi- fied as obese. Those children with a BMI greater than or equal to the 85th percentile but less than the 95th percentile for age and sex should be placed in the over- weight category. Because adolescent obesity is predictive of adult obe- sity, treatment of childhood obesity is desirable. 36 The goals of therapy in uncomplicated obesity are directed toward healthy eating and activity, not achievement of ideal body weight. Families should be taught awareness of current eating habits, activity, and parenting behavior and how to modify them. In children with complica- tions secondary to the obesity, the medical goal should be to improve that problem. The weight loss interven- tions should include all family members and caregiv- ers; begin early at a point when the family is ready for change; and assist the family to learn to monitor eating and activity patterns and to make small and acceptable changes in these patterns. Overweight and obese children should be treated using a staged method based on their age, BMI, and related comorbidities. Dietary goals should focus on well-balanced meals with a healthy approach to eating. Specific strategies can include reduction of specific high- calorie foods or an appropriate balance of foods that are low, medium, and high calorie. Commercial diets should be used with caution. Pharmacologic therapy and bar- iatric surgery should be reserved for children with com- plications and for severe obesity, respectively. ■■ Obesity, which refers to excess body fat resulting from consumption of calories in excess of those expended for exercise and activities, reflects the influences of heredity; socioeconomic, cultural, and environmental factors; psychological influences; and activity levels. ■■ Overweight and obesity are determined by measurements of body mass index (BMI) and waist circumference, which is used to determine the distribution of body fat in terms of upper or lower body obesity. In upper body or central (visceral) obesity, the adipocytes release free fatty acids and adipokines that increase cardiometabolic risk and produce many of the adverse effects of obesity. SUMMARY CONCEPTS

 Childhood Obesity Obesity is the most prevalent nutritional disorder affecting the pediatric population in industrialized countries in the world. 35,36 The definition for obesity in children is a BMI at or above the sex- and age-specific 95th percentile, while a BMI between the 85th and 95th percentile is defined as being overweight. 34 These criteria have been selected because they correspond to adult BMIs of 30 and 25, respectively. 37 The findings from the National Health and Nutrition Examination Survey (NHANES), conducted between 2008 and 2010, indicated that 16.9% of children and adoles- cents were obese. 35 The major concern of childhood obesity is that obese children will grow up to become obese adults. Health care providers are now beginning to see hypertension, dyslipidemia, type 2 diabetes, and psychosocial stigma in obese children and adolescents. In North America, type 2 diabetes now accounts for half of all new diagno- ses of diabetes (type 1 and type 2) in some populations of adolescents. 38 In addition, there is a growing concern that childhood and adolescent obesity may be associ- ated with negative psychosocial consequences such as low self-esteem and discrimination by adults and peers. 34 Childhood obesity is determined by a combination of hereditary and environmental factors. It is associated with obese parents, gestational diabetes and excessive weight gain during pregnancy, formula feeding, par- enting style, parental eating habits, energy-dense food choices, erratic eating patterns, ethnicity, and sedentary lifestyle. 34–36,38,39 Children with overweight parents are at highest risk. One of the factors leading to childhood obesity is the increase in inactivity. Increasing percep- tions that neighborhoods are unsafe has resulted in less time spent outside playing and walking and more time spent indoors engaging in sedentary activities such as television viewing and computer usage. Television view- ing is associated with consumption of calorie-dense snacks and decreased indoor activity. Studies have shown a 10% decrease in obesity risk for each hour per day of moderate to vigorous physical activity, while the risk increased by 12% for each hour per day of televi- sion viewing. 38 Obese children also may have a deficit in recognizing hunger sensations, stemming perhaps from parents who use food as gratification. The impact of fast food, increased portion size, calorie density, sugar- sweetened soft drinks and foods (especially fructose), 22 and high-glycemic-index foods are likely contributing to the increased weights in children and adolescents. Diagnosis and Treatment. Given the enormity of the problem of overweight and obesity in children, the American Medical Association (AMA), the Department of Health and Human Services’ Health Resources and Services Administration (HRSA), and the Centers for

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