Chapter 60 Overweight and Obesity in Childhood
PATHOPHYSIOLOGY
Today’s rapid increase in overweight and obese children is considered a critical public health problem related to early-onset cardiovascular disease (CVD) morbidity and mortality. CVD is the number one cause of death of adults in Western society today and is a contributing factor to mortality worldwide.
The estimated annual health care costs attributed to obesity and some comorbid diseases in the United States are about $117 billion dollars. The complex interaction of factors surrounding obesity, behavior choices, environmental influences, and genetic predisposition affect all aspects of pediatric health care.
The World Health Organization (WHO) placed overweight in the list of top 10 health risks in the world, and the top 5 in developed nations. The American Heart Association (AHA) lists the significant long-term effects of childhood overweight and obesity to include cardiovascular disease, type 2 diabetes, metabolic and orthopedic abnormalities, asthma, sleep apnea and some cancers. Psychosocial consequences of adolescent obesity reported by the American College of Sports Medicine (ACSM) include social isolation, high-risk behavior (alcohol and drug use, and early sexual experimentation), low self-esteem, depression, and eating disorders.
The pathophysiology of overweight and obesity is described as an imbalance between energy intake and energy expenditure. The regulation of energy intake requires the body to differentiate short-term signals controlling hunger, food intake, and satiety from long-term signals reflecting energy stores and lean tissue. Overall, the function of food regulation and ingestion originates from signals in the brain and hormonal releases.
Adipose tissue development into adipocytes in the fetus begins midway to late in the third trimester and continues throughout life. Crucial periods of adipose tissue development can be affected by infant feeding practices, puberty, and other factors.
Additional research is required into the development and regulation of adipocyte number and volume. Intrauterine influences have been correlated with environmental factors and have emerged as an important area of research today. Epidemiologic investigation has identified a direct positive relationship between birth weight and body mass index (BMI) later in life.
Puberty and adolescence are marked by influential physiologic and psychologic changes in both boys and girls. In boys, fat-free mass increases, and body fat as a percentage of body weight decreases. In adolescent females, both fat and free mass increase, and fat-free mass as a percentage of body weight decreases. The influence of hormones on fat distribution is evident and is differentiated by sex. Adolescent fat stores are centralized, with increased amounts of subcutaneous and visceral fat in the abdominal regions in females, and even more so in males. Young females typically demonstrate fat deposits in the breasts, the hips, and the buttocks. Adolescence is a critical period of development in prevention of adult obesity and obesity-related comorbidities in both sexes.
BMI is a measurement tool defining the terms overweight and obesity in children and adults. BMI percentile calculations are based on the ratio dividing the weight (kilograms) by the height in meters squared, correlating with age and sex. Growth charts using BMI-for-ages 2 to 20 years by sex can be accessed at www.cdc.gov/growcharts. For children, a BMI between the 85th and 95th percentiles is considered overweight, and a BMI at or greater than the 95th percentile is considered obese. It is estimated that of adolescents with a BMI at or above the 95th percentile, approximately 50% will become obese adults. Adiposity is another marker for determining at risk status for overweight and obesity and can be evaluated using the skinfold test. Based on the compelling evidence of an obesity epidemic, The American Academy of Pediatrics (AAP) and the Institute of Medicine (IOM) recommend annual assessments of BMI as a strategy to affect the problem of childhood obesity (Box 60-1).
Box 60-1 BMI for Children and Teens (sometimes referred to as “BMI-for-age.”)
For the 2000 CDC Growth Charts and additional information, visit the National Center for Health Statistics website: www.cdc.gov/growthcharts.
From Centers for Disease Control and Prevention
BMI is used differently with children than it is with adults.
In children and teens, body mass index is used to assess underweight, overweight, and risk for overweight. Children’s body fatness changes over the years as they grow. Also, girls and boys differ in their body fatness as they mature. This is why BMI for children, also referred to as BMI-for-age, is sex- and age-specific. BMI-for-age is plotted on sex-specific growth charts. These charts are used for children and teens 2 to 20 years of age. For the 2000 Centers for Disease Control and Prevention (CDC) growth charts and additional information see Appendix E. Each of the CDC BMI-for-age sex-specific charts contains a series of curved lines indicating specific percentiles. Health care professionals use the following established percentile cutoff points to identify underweight and overweight in children.
| Underweight | BMI-for-age <5th percentile |
| Normal | BMI-for-age from 5th percentile to <85th percentile |
| At risk of overweight | BMI-for-age from 85th percentile to <95th percentile |
| Overweight | BMI-for-age ≥95th percentile |
Biology (genetics) is the contributor to individual differences in weight and height, whereas trends in rapid weight gain are primarily attributed to changes in the environment and behavior factors. Modern lifestyles in the United States and developed countries demonstrate increased consumption of energy and decreased energy expenditure. Factors contributing to overconsumption of energy include availability and variety of good-tasting, inexpensive, energy-dense foods served in large portions. Factors related to a decrease in total energy expenditure include a marked decline in overall physical activity at school and in daily living, and increased sedentary leisure time spent watching television, surfing the Web, and playing video games.
A number of factors have been identified as contributing to childhood obesity. Genetic factors related to childhood obesity include maternal obesity, gestational diabetes, and genetics. Increased incidence of obesity in adolescents is related to adolescents who engage in high-risk behaviors because of peer pressure (smoking, ethanol use, and premature sexual experimentation). Social factors related to childhood obesity include lack of parental monitoring, single-parent families, educational level, and access to safe recreational facilities. Dietary factors associated with childhood obesity include reduced daily recommended dietary intake (RDA) of fruits and vegetables, absent or limited breast-feeding practices, high consumption of soft drinks, lack of family meals, dietary factors during infancy, meal preparation, and portion size.
Parental denial or lack of understanding related to overweight or obesity and associated psychosocial and physiologic health care disparities has been associated with childhood obesity. Parents and caregivers who have problems with health literacy and/or an inability to communicate effectively with health care providers will have problems in managing their child’s diet, lifestyle changes, and exercise routine to effectively deal with their child’s obesity.
The public health challenge of preventive pediatric obesity is best addressed with early recognition of preventable and/or modifiable risk factors: diet, exercise, lifestyle, and parental education. Multidisciplinary strategies are needed from primary, secondary, and tertiary health care professionals to prevent, educate, treat, manage, and engage in research efforts to eradicate the epidemic of childhood obesity. The efforts of family, society, insurance companies, and policy makers are required to combat the challenges of childhood obesity threatening current and future generations.
INCIDENCE
1. The high incidence of overweight children 5 years of age and younger is a major health problem identified by the Centers for Disease Control (CDC) among all ethnic groups.
2. The ratio of overweight boys to girls is about 1:1, although there is ethnic variability.
3. The prevalence of obesity in Mexican-American males (42.8%) aged 5 to 19 years is greater than in African Americans (31.0%) or whites (29.2%).
4. Obesity in African-American females occurs at a rate of 40.1%, greater than that in Mexican Americans (36.6%) or whites (27%).
5. Of U.S. children ages 8 to 16 years, 20% are physically active fewer than 2 times a week.
6. Over the last 2 decades the incidence of overweight or obesity has increased by 50%.
7. Four or more hours of daily television watching is related to increased BMI.
CLINICAL MANIFESTATIONS
COMPLICATIONS
1. Cardiovascular disease: hypertension, elevated cholesterol and triglycerides, stroke
3. Endocrine: diabetes Type 2, insulin-resistance syndrome
4. Gastrointestinal: gallbladder disease, colon cancer
5. Gynecologic: irregular menses, abnormal growth acceleration
6. Orthopedic: osteoporosis, growth plate abnormalities
7. Psychosocial: depression, low self-esteem, social isolation, eating disorders, suicide, behavior problem and syndromes, high-risk behavior (alcohol use, smoking, illicit drug use, early-onset sexual experimentation)
8. Respiratory: asthma, sleep apnea, snoring and other sleep-related disturbances
9. Increased risk for morbidities and early mortality in adulthood
LABORATORY AND DIAGNOSTIC TESTS
Refer to Appendix D for normal values and ranges of laboratory and diagnostic tests. The following are based on present and past medical history, physician preference, and health care coverage.
1. Annual BMI—recommended as the primary method to assess obesity in children and adolescents. BMI at or above 95th percentile is the clinical definition of obesity (Box 60-1).
2. Skinfold measurement—measurement involving skinfold thickness of the triceps. Clinicians must be proficient at using skin calipers if this test is to be accurately predictive. BMI and the skinfold measurements are equally predictive of the morbidity of obesity.
3. Sleep studies—gold standard is polysomnography assessing the electroencephalogram (EEG), electromyogram, electrooculogram, heart rate, respiratory rate, and behavior. It is performed to determine the presence of sleep disorders.
4. Pulmonary function test—to monitor children and adolescents with known respiratory disease and growth hormone deficiency, and to establish reduced physical activity as an etiology for obesity; in addition, evaluates fitness in patients with congenital heart diseases.
5. Diabetes management per hemoglobin A1C—to monitor blood glucose levels over a 5- to 6-week period; predicts a mean glucose level
6. Complete blood count—to evaluate the hemoglobin, hematocrit, white, red, and platelet cell counts, cell morphology
7. Lipid profile—to determine general baseline, and to assess for premature coronary artery disease, familial hypercholesterolemia, and rare but possible xanthomas
8. Hormone studies (luteinizing, follicle-stimulating or testosterone levels)—baseline studies to evaluate any potential growth, pituitary, or hormonal abnormality
9. Thyroid panel—associated with short stature or Cushing’s or Turner’s syndrome
10. Liver function—to assess for potential steatosis or steatohepatitis, which can be asymptomatic
11. Chemistry panel—to evaluate electrolyte imbalances
12. Electrocardiogram (ECG)—based on significant past and present medical history; used to assess for cardiac arrhythmias
13. Genetic evaluation—to determine if obesity is associated with physiologic, genetic, and/or psychologic history
MEDICAL MANAGEMENT
Medical management begins with complete physical examination including BMI and skinfold measurements. A complete psychosocial history is conducted including identification of high-risk behaviors. Laboratory and diagnostic tests are ordered to collect data that will contribute to the diagnostic work-up (refer to foregoing Laboratory and Diagnostic Tests section). Parents and child may be asked to complete a personal dietary and activity diary on the child to gather relevant information.
Based upon the comprehensive assessment, treatment modalities and referrals are initiated that can include dietary and weight management, exercise programs, and support groups. In addition, referrals are made as appropriate to a clinical psychologist, psychiatrist, and behavior modification programs such as Weight Watchers and Overeaters Anonymous. Consistent follow-up and monitoring is needed to provide ongoing support and treatment to ensure positive outcomes. Treatment modalities should accentuate long-term permanent changes, not rapid or short-term diet and activity programs.
Depending on the school district, the school may have weight management programs and educational programs related to nutrition and exercise. School nurses are integral members of the team managing the child’s long-term management needs. School nurses perform annual BMI screening and identify at risk children and adolescents. Physical education teachers may be the professional who identifies a student in physical education class who has a BMI at or above the 85th percentile, and may refer the child to appropriate community-based resources and support groups.
NURSING ASSESSMENT
1. Obtain information on the child’s present and past history and complaints.
4. Identify ethnicity and cultural beliefs.
5. Identify support systems (e.g., family, friends, teachers, health care).
6. Identify barriers to health promotion (access to health care, transportation, role models).
7. Make referrals as needed to social services, community clinics, interpreter services, and so forth.
NURSING INTERVENTIONS
1. Promote multidisciplinary approach in childhood obesity programs, including dietary changes, nutritional information, physical activity, behavior modification, parental involvement and education, and setting realistic goals.
2. Promote a positive, nonthreatening environment with parents and/or caregivers when discussing lifestyle changes, weight management, diet, and physical activity related to overweight or obesity.
3. Answer questions, reinforce information, and address parental and child’s concerns related to child’s problems with being overweight or obese.
4. Refer to appropriate community resources for childhood obesity.
5. Provide culturally appropriate education in schools and communities related to nutrition and regular physical activity based on dietary guidelines for Americans for individuals of all ages.
Box 60-2 Long-Term Advocacy Interventions
• Educate health care providers about overweight and obesity risk factors across the life span.
• Support the efforts of pediatric health care providers to promote and eradicate childhood overweight and obesity.
• Encourage health care providers, parents, and community members to get involved at the local, state, and federal levels to promote healthy living and decrease the incidence of overweight and obesity in children and adolescents.
• Collaborate with school nurses to facilitate annual BMI screening and routine follow-up with students at risk for being overweight and with overweight and obese students.
• Collaborate with physical education teachers to identify students who have a BMI at or above the 85th percentile through physical education classes; consult with students in a nonthreatening manner and refer to school nurse for appropriate interventions or referrals.
• Educate expectant parents on the benefits and potential long-term effects of breast-feeding.
• Facilitate task forces in community hospitals and nursing programs in the fight against childhood obesity.
• Support private and public funding and research to endorse effective strategies in the prevention of overweight and obesity in children and adolescents.
• Provide culturally appropriate education in schools and communities related to nutrition and regular physical activity based on dietary guidelines for Americans for individuals of all ages.
• Support the study of the prevalence of overweight and obesity among ethnically diverse individuals, and according to sex, social-economic status, and age groups, to identify effective and culturally competent interventions.
• Provide access to interpreter services to promote school and community educational efforts related to primary, secondary, and tertiary prevention in the treatment of childhood obesity.
• Promote family education and empower parents through anticipatory guidance; help them to recognize the impact they have on their child’s lifelong habits of nutrition, diet, and physical activity behavior(s).
• Use and refer parents to computer information resources promoting physical activity through the Obesity Education Initiative at www.nhlbi.nih.gov/about/oei/index.htm.
• Foster relationships with community agencies serving low-income families to develop programs and educational materials related to childhood obesity (refer to Appendix G).
• Support marketing research to promote healthy food choices and regular physical activity.
Discharge Planning and Home Care
1. Integrate the CDC nutrition and physical activity programs at www.cdc.gov/nccdphp/dnpa/programs/index.htm into long-term therapeutic home care program.
2. Establish partnerships with parent(s) in all stages of therapeutic plans related to overweight or obesity.
3. Promote and provide continuing information to parents and caregivers related to changes in regimen or special needs related to dietary and weight management programs.
4. Promote physical activity of at least 30 minutes a day, 4 to 5 days a week.
5. Recommend the Kids Walk to School program at www.cdc.gov/nccdphp/dnpa/kidswalk/resources.htm.
CLIENT OUTCOMES
1. Child or youth will maintain BMI below 85th percentile.
2. Parent(s) and child or adolescent will verbalize understanding of therapeutic regimen related to dietary and nutritional guidelines, and physical activity to decrease the incidence of overweight and obesity.
3. Professionals, families, and/or youth will access available health care resources to promote and limit the incidence of overweight and obese children and adolescents.
4. Interpreters will limit language and cultural barriers for individuals and/or family(s) in the promotion of healthy behaviors related to diet, nutrition, exercise, and health disparities in the prevention of overweight and obesity.
5. Parent or adolescent will verbalize age-appropriate understating of the long-term effects of breast-feeding and weight management.
6. Parent, child, and/or adolescent will verbalize understanding of the cardiovascular mortality and morbidity related to overweight and obesity.
American Academy of Pediatrics. Policy statement. Committee of nutrition; prevention of pediatric overweight and obesity. Pediatrics. 2003;112(8):2.
CDC Center for Disease Control and Prevention. Overweight and obesity. (website) www.cdc.gov/nccdphp/dnpa/obesity/index.htm Accessed July 25, 2006
Baker S, et al. Overweight children and adolescents: A clinical report of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition, Daniels SR et al: Overweight in children and adolescents: pathophysiology, consequences, prevention and treatment. Circulation. 2005;111:1999.
Doak CM, et al. The prevention of overweight and obesity in children and adolescents: A review of interventions and programmes. Obesity Rev. 2006;7:111.
Hill JO, et al. Obesity and the environment: Where do we go from here? Science. 2003;299(5608):853.
National Institute for Health Care Management. Childhood obesity—advancing effective prevention and treatment: An overview for health professionals. [NIHCM Foundation (serial online)] www.nihcm.org/ChildObesityOverview.pdf, 2007. Accessed Feb. 19, 2007
Snethen JA, Broome ME, Cashin SE. Effective weight loss for overweight children: A meta-analysis of intervention studies. J Pediatr Nurs. 2006;21(1):45.
Story MO, Tracy C. Building evidence for environmental and policy solutions to prevent childhood obesity: The healthy eating research program. Am J Prev Med. 2006;30(1):96.
