The rate of obesity in children, defined as having a weight greater than expected for height, is increasing at an alarming rate. Obesity is caused by ingesting more calories than are expended. According to the latest studies by the National Health and Nutrition Survey (NHANES III), 22% of children qualify as obese, up from 15% ten years ago.

In Iowa, Pediatric Nutrition Surveillance System (PedNSS) data collected at WIC (see insert page 2), and shared with the federal Centers for Disease Control and Prevention, confirm that the prevalence of obesity in Iowa WIC children increased from 7.6 percent in 1985 to 10.1 percent in 1999. The measurement frequently used in the assessment of obesity is Body Mass Index (BMI). Standard tables are available that display BMI percentiles per age.

Obesity in children is associated with specific complications:

• Poor self-esteem, which can exacerbate the obesity
• Depressive disorders, found in about 10% of obese children
• Sleep apnea secondary to upper airway obstruction. Sleeping habits should be detailed in obese children. A child with a history of loud snoring or pauses in breathing while sleeping should undergo a formal sleep study.
• Steatohepatitis
• Hypertension
• Atherosclerosis
• Type II diabetes mellitus. This disorder, increasing at an alarming rate in adolescents, correlates strongly with obesity. Obese children should be asked about such symptoms as excessive thirst and frequent urination.

The University of Iowa is also involved in studies looking at insulin resistance and correlations with different genetic mutations in children with obesity, including the glucocorticoid receptor gene. The glucocorticoid receptor is present in all cells of the body. A mutation of this receptor has been associated with increased sensitivity to glucocorticoids as well as insulin resistance.

Treatment

The options available for the treatment of obesity in children are limited. In adults with obesity, medications are available to help suppress appetite or interfere with the absorption of fats. The use of these medications has not been studied in pediatric populations. In obese children, the mainstays of therapy include diet and exercise, both important in order for weight management to be successful. In growing children the goal for weight management is often weight maintenance, or staying at a current weight while the child grows taller, thus achieving a more appropriate BMI. Caloric goals can best be estimated by working with a nutritionist, who can counsel the family about such goals, how to estimate portion sizes, and how to make appropriate food choices. Exercise should consist of 30 minutes of aerobic activity (brisk walking, swimming, or bike riding) every day.

Behavior therapies are also helpful in the treatment of obesity. The best technique is for the child to self-monitor, keeping a diary of exercise and foods eaten. If the parent of an older child tries to regulate the diet, the plan will often fail as the child finds other ways to obtain food. Behavioral changes that are important include sitting down at a table to eat, rather than eating in front of the television, as studies have shown that children who watch TV are likely to ingest more calories. Meals should be eaten on a regular schedule, so that a child learns appropriate timing for meals and minimizes snacks between meals. Building self-esteem and encouraging the child to approach weight management with a positive attitude will also improve success.

Obesity is a significant concern in our society today. Obese children tend to become obese adults; complications from obesity include cardiovascular disease, diabetes, and hypertension. Good preventative care will involve identifying obesity, identifying any complications, and initiating treatment.

Michael Tansey MD, Pediatric Endocrinology and Diabetes, University of Iowa Hospitals and Clinics, (319) 356-4511, michael-tansey@uiowa.edu.