With the epidemic of obesity in children, we are seeing an emergence of traditionally adult diseases in this younger population. In addition to medical issues, the psychological sequelae of obesity during some of the most formative years of life have significant impact on how these children and adolescents adapt as effective members of society (Table 48–1). The potential ramifications of these issues on our country's health-care system and on the future health of our nation are quite alarming.
As in adults, obesity in adolescents is associated with a large number of health consequences. Although these obesity-related comorbidities occur more frequently in adults, significant consequences of obesity as well as the antecedents of adult disease occur in obese children and adolescents.
Metabolic Syndrome and Cardiac Risk Factors
The metabolic syndrome is a cluster of risk factors that links insulin resistance, hypertension, dyslipidemia, type 2 diabetes, and other metabolic abnormalities with an increased risk of later cardiovascular disease.46 This syndrome, at first thought to be only an adult phenomenon, is unfortunately becoming more prominent in adolescents and children. Cook and colleagues47 studied the prevalence of metabolic syndrome in a sample of adolescents from the third National Health and Nutrition Examination Survey (NHANES III) and found the syndrome to be present in 28.7% of overweight adolescents (BMI ≥ 95th percentile). More recent findings, using modified criteria, suggest that the metabolic syndrome is far more common (nearly 50%) among overweight children and adolescents and that its prevalence increases directly with the degree of obesity.48
Obese children and adolescents have increased blood lipids as well as glucose intolerance and diabetes.49–51 Although thought to be a traditionally “adult” disease, type 2 diabetes is becoming shockingly more common in obese children and adolescents. The incidence among adolescents has increased 10-fold since 1982 and is felt to account for one-third of all new cases of diabetes in children,52 these numbers being even higher in women and Hispanics.53
Hypertension is yet another example of a predominantly adult disease, with a rising incidence in the pediatric population.54–56 The long-term consequences are as yet unknown; however, there is some evidence that childhood hypertension can lead to adult hypertension, and thus the associated development of left ventricular hypertrophy, atherosclerosis, and even early development of coronary artery disease.44,57–62
Sleep apnea is another significant health consequence of childhood obesity. Symptoms which may include snoring, poor school performance, enuresis, and hyperactivity can have significant effects on quality of life.63,64 The prevalence of obstructive sleep apnea (OSA) in obese children and adolescents is quoted anywhere from 24% to 59%65–68; however, a direct correlation between reduction in OSA indices and reduction in BMI has not been demonstrated.69
Pseudotumor cerebri (PTC) is a rare disorder characterized by increased intracranial pressure. Symptoms include headache, visual field disturbances (the most severe is blindness), and pulsatile tinnitus.70,71 PTC in adolescents has a direct correlation with obesity.72,73 Progressive visual impairment indicates the need for aggressive treatment of obesity in patients with this disease.44 Weight loss is associated with dramatic improvement in symptoms and improvements in objective measures of the disease including visual field abnormalities and lumbar pressures.74–76
Overweight children are susceptible to developing orthopedic complications because the tensile strength of bone and cartilage is not evolved to carry substantial quantities of excess weight. As a result, the excess weight carried by obese children is associated with bowing of long bones, which may cause injury to the growth plate and result in slipped capital femoral epiphysis, genu valga, tibia vara (Blount's disease), scoliosis, osteoarthritis, and other injuries.44,66 Both slipped capital femoral epiphysis and Blount's disease are pediatric orthopedic injuries that are highly associated with obesity in children, and prompt and sustained weight reduction is essential in their treatment.77,78
Few problems in childhood have as significant an impact on emotional development as being overweight. Adolescence in and of itself is a tumultuous period of emotional and interpersonal growth and development for children. It is not surprising therefore that the psychosocial consequences of obesity may in fact be the most prevalent of associated comorbidities. Obesity is one of the most stigmatized and least socially acceptable conditions in childhood.79 Health related quality of life studies document marked impairments in all domains including physical functioning, emotional well-being, social relations, and school functioning in adolescents with severe obesity (BMI ≥ 40 kg/m2). This level of impairment is even worse than for those youth with chronic disease or cancer.64,80,81
Relative to average-weight peers, obese adolescents, particularly females, are socially marginalized and are less likely to be nominated by their peers as a friend.79 Given the importance of peer acceptance, body image, and physical fitness to social and emotional development, overweight may have lasting implications on child development and adolescent well-being. These adolescents are clearly at considerable risk of continued and mounting psychosocial impairment and poor developmental adaptation.82 Among severely obese adolescents, there is a high incidence of low self-esteem, sadness, and moderate to severe depressive symptoms. Extreme obesity is associated with an increased risk of suicide and suicidal ideation among adolescents.66,83,84 The impact of this psychosocial impairment is grand, and some studies even suggest that obesity may be the worst socioeconomic handicap that women who were obese adolescents can suffer.44,45