First Published: Friday, March 8, 2002
Pediatric Obesity in the Clinical Setting: Epidemiology of Childhood Obesity.
Primary Care Interventions, and Needs Assessment for Future Prevention
Jennifer R. McCarthy, MPH, Mary Ann Burg, MSW, PhD,
Kristen Smith, MPH, Cathy Burns, BSN, MA
University of Florida
Dept. of Comm. Health & Fam. Med.
706 SW 4th Avenue
Gainesville, FL 32601
Pediatric obesity has become a modern
epidemic of considerable import.
It has also become the focal point for numerous health studies. Most often defined as the Body Mass Index (BMI) for age and height over the 95th percentile, pediatric obesity has reached its way into every ethnic group and every class in America. Obesity in children is a predictor of many secondary cardiovascular diseases and is not easily treated. It is often perpetuated from generation to generation in obese families as lifestyle patterns and health behaviors are usually shaped in the home. The increasing rate of pediatric obesity in the United States is unsettling when considering the medical toll and the annual expenditures of treating obesity and its sequellae. Accelerated prevention activities in community and primary care settings may be the most crucial component to controlling the burden of pediatric obesity in our country.
Finding prevention modalities that are both effective and feasible may be more problematic than it would first seem. Four significant barriers to prevention and intervention with childhood obesity are:
- time available for counseling families,
- lack of effective treatment protocols,
- reimbursement, and
- lack of commitment of primary care providers to care for affected patients.1
The aim of this paper is to review the current literature on pediatric obesity prevention and treatment. This review includes: 1) an examination of the most current epidemiological data and existing literature which contributes to the rising awareness of pediatric obesity as a necessary focus for general practitioners, 2) published interventions which have attempted to reverse the effects of childhood obesity by targeting overweight children in a clinical setting, 3) and, an assessment of the existing needs for pediatric obesity interventions and prevention within family practices across the country. Articles selected for this review were identified through a computerized Medline literature search using the following key words: pediatric obesity, childhood obesity, obesity prevention, obesity interventions, obesity and primary care. The search was limited to dates of publication of articles ranging from 1991 to 2001. Cross-references from articles produced by Medline search results were additionally used.
I. Rationale: Epidemiology of Pediatric Obesity in America
Several large cohort studies have confirmed the upward trend in the prevalence of obesity in children.2 As of 2001, approximately 22% of children in the United States were overweight (above the 85th percentile) and more than 11% of children were obese (above the 95th percentile).2 According to the most recent data from the Centers for Disease Control's National Health and Nutrition Examination Survey (NHANES), the country's most extensive health and nutrition survey, the past two decades have seen the number of overweight children and teenagers nearly double.3 According to data from the 1999 NHANES, 13% of children ages 6-11 years old and 14% of adolescents ages 12-19 years old were obese,3 compared to 1983, when only 8.5% of U.S. children were obese.4 Between 1973 and 1994, average body weight of children increased by .2 kilograms per year.2 Each race, sex, and age group have shown increases in obesity rates, although the changes have been the greatest for older preschool children.4
Obesity is the cause of 300,000 deaths each year.5 Pediatric obesity seriously increases the risks of acquiring obesity-related medical conditions later in life if not during adolescence.2 The increasing rate of pediatric obesity has undoubtedly contributed to the significant 10-fold increase in Type II Diabetes in kids between 1982 and 1994.2 Research has shown an association between obesity in childhood and blood pressure, diabetes, respiratory disease, adult obesity, orthopedic disorders, and psychological disorders.4 Overweight individuals are also at increased risk for coronary heart disease, dyslipidemia, gallbladder disease, some cancers, gout, and arthritis.6 Childhood obesity may even lead to menstrual problems in women in early adulthood.7 The Bogalusa Heart Study revealed that when the guidelines for the National Cholesterol Education Program were used to evaluate risk status, 91% of participants with high cholesterol at follow-up could have been identified during childhood with cholesterol screening or obesity measurements.2 An autopsy study revealed that atherosclerotic plaques and cardiovascular disease had already begun in young adulthood.2
The Harvard Growth Study showed that men who were overweight during adolescence were twice as likely to die as men in the lean group, and that women who were overweight adolescents were eight times as likely to have problems with activities of daily living than their lean counterparts.2 A Danish study of men confirmed that men over 18 with BMIs over 31 experienced excess mortality from all causes when compared to national Danish vital statistics.8 Strangely enough, one 1997 study even reported that adults who were obese as children would have increased mortality independent of their adult weights.5
Childhood obesity also increases the likelihood of emotional and social problems in children and adults. It has been reported that as early as six years old overweight children have been described as lazy, stupid, ugly, and dishonest.8 The Bogalusa Heart Study revealed that being overweight at baseline with a BMI at or above the 95th percentile was associated with lower income, lower intelligence, and lower parental education for women.2 The Bogalusa study also showed that women who were overweight as adolescents were less likely to get married, had lower household incomes, and completed fewer years of school. Overweight men were less likely to marry than their non-overweight counterparts.2 Additionally, overweight women were more likely to have poorer job chances.7
Obesity in children is more prevalent among minority groups than among the Caucasian majority.2 The highest prevalence of obesity in girls is found among non-Hispanic African Americans, with rates of 17-31% for girls 6-11 and 15-30% in 12-17 year-olds.2 For boys, the highest prevalence of obesity is found in Mexican Americans, with 18-33% of 6-11 year-olds and 13-27% of 12-17 year-olds being obese.2 Among grown women, 1997 data reported that 34% of non-Hispanic whites, 52% of non-Hispanic blacks, and 50% of Mexican Americans were overweight.6 Some women of color may be at increased risk because of their sedentary behaviors and high-fat "diets of poverty".9 According to NHANES III, the late '90s also showed a significant decrease in physical activity among girls. Approximately 20% of 14-16 year-old girls reported taking part in one or fewer episodes of vigorous physical activity in a week, while 26% of kids reported watching greater than or equal to 4 hours of television per day.2 This same data revealed that boys and girls who watched this amount of television also had the highest skin fold thicknesses and BMIs, and that 43% of non-Hispanic African Americans were watching TV to this extent.2 Interestingly, BMIs were not significantly correlated with physical activity but were correlated with sedentary behavior.2
Data indicates that 65% of high school students participate in vigorous activity three or more days per week, and 27% participate in moderate physical activity on five or more days per week.10 Seventy-three percent of 9th graders but only 61% of 12th graders participate in physical activity on a regular basis.10 Male students are much more likely to participate in vigorous physical activity, moderate physical activity, and team sports than their female classmates.10 High school students' daily participation in physical education dropped from 42% in '91 to 29% in '99. 10 This downward trend may continue as many public school systems face increasing budget cuts leading to a reduction of physical education programs.
Pediatric obesity begins early in life and it often persists into early and later adulthood.2 Eighty percent of obese children become obese adults.5 It has been reported that the more severe and earlier the onset of pediatric obesity, the more severe the adult obesity will be.5 Some researchers have determined that the most accurate predictor of adult obesity is weight at the age of 18, while weight at the age of 13 or under being only moderately predictive.2 Another study agreed that the relationship between adolescence and adulthood adiposity was greater than the relationship between childhood and adulthood adiposity.7 Additionally, the odds ratio for being overweight in adulthood has been reported to be significantly greater for children with BMIs in the 75th percentile as compared to the 50th percentile.2
Obesity has also been linked to familial patterns and behavioral relationships.
One study showed that the risk of adult obesity was greater at any age in both
obese and non-obese children if at least one parent was obese.2 The association
between parent and child obesity was most pronounced among children 10 years-old
or younger.2 Another study published in 1996 determined that children had an
80% chance of becoming obese if both parents were obese, and a 40% chance of
becoming obese if one parent was obese.11 When neither parent was obese, the
odds dropped to 7%.11 The same study reported that children with obese mothers
were 2.5 times more likely to become obese than children with non-obese mothers.11
A mother's activity level and the frequency of her exercise was also associated
with her child's performance in the one mile walk/run, according to a 1991 study.12
Parental neglect may predict an increased risk of obesity in young adulthood.11
Cultural factors, such as a mother taking pride in a fat baby, giving food as
a reward, or believing that rapid weight gain is a symbol of good health have
also been imputed as causes of pediatric obesity. 11 Also, it appears that no
difference exists between attitudes toward physical activity or taking part
in physical activity between obese and non-obese children, and that physical
activity for both groups is low.12
The best data indicates that the primary reasons for the increasing upward trends of childhood obesity are the combination of sedentary behaviors and diet.5 The fat content in American diets has increased and more foods with higher fat contents are now available.5 Studies which have utilized self-report of food eaten have shown very little evidence that obesity is caused by overeating5. In 1998, a publication was released reporting that grams of fat consumed have increased over time, beverage consumption in sodas has increased, especially for adolescent males, and that grain consumption has increased while fewer dairy products are being consumed.13 There has also been a substantial increase in the consumption of carbohydrates.13
II. Obesity Interventions in Clinical Settings
A few studies have examined rates of diagnosis and treatment for pediatric obesity in outpatient settings. Studies indicate that health care providers recognize and initiate treatment for less than 20% of obese children.5 Physicians who say they specialize in obesity range from 4.5% of family practitioners to 36.4% of endocrinologists.14 Primary care providers reportedly view obesity management as their responsibility, but may feel ill-equipped to appropriately intervene, often refer obese patients out, and may tend to "blame the victim" for his or her lack of self-control.14 Due to the feeling of incompetence some clinicians experience, mild cases of obesity may go undiagnosed and untreated.14 A cross-sectional survey of nurses found that nurses were likely to give advice on weight control, but that they had low expectations of positive outcomes in obese patients.15 A historical cohort study utilizing chart audits reported that patients diagnosed with obesity were more likely to receive weight and diet counseling, but no more likely to receive exercise counseling as non-obese patients.16 It is clear that there are significant clinical gaps in obesity prevention and intervention.
It is important to consider the value of intervening on obesity before individuals reach adulthood. An overall assessment of obesity interventions focused on adult patients confirms that short-term weight loss seems possible among adults, while long-term success is highly unlikely. According to one study, less than 5% of adults who lose weight are able to maintain their weight loss after five years, and 62% of adults regain all of their lost weight.5 Intervention studies aimed at adult weight loss have reported similar findings. A pilot study published in 1999 reported that a weight-loss workbook approach to weight control, designed to be used with a family physician, was successful at one month in only 32% of patients.17 The same study reported that a discussion of weight loss was more likely to be continued with men than women after using the workbook.17 This intervention's low success rate was considered less due to patients' lack of interest or adherence, and more due to physicians not accurately assessing patient's readiness for change.17 Another very recent study reported that increasing treatment length and putting more emphasis on energy expenditure just modestly improved long-term weight loss in adults.18
On the other hand, it has been shown that obesity prevention and intervention programs for children have more potential for success and long-term benefits. A primary reason for success at younger ages is that children's' behavior patterns are not yet fully formed, and are thus more modifiable.5 Family-based interventions for childhood obesity have demonstrated great success. One non-clinical study revealed that when parents were included in a weight loss program with homework and take-home videos that more than half of the parents changed their eating habits, too.19 Other studies have shown that providing appropriate eating and lifestyle behavior education to parents reduces the prevalence of obesity in children for periods of three months to three years when compared to families not receiving advice or support.20 It has also been reported that short and long-term weight regulation effects are improved if at least one parent is included with the child as an active participant in treatment.21 Family and friend support has also been reported to benefit a patient trying to lose weight.21 All members of the family or friends participating are then very likely to benefit. 20
A specific example of a pediatric obesity intervention used in the clinical setting is the SHAPEDOWN method, a clinical process developed at the University of California, San Francisco, in 1979. This method relies on a series of four steps: 1) identification of the obesity, 2) preventive care, 3) comprehensive assessment, and 4) treatment.22 A full SHAPEDOWN process includes the following steps: a) a clinician first helps a parent and child recognize the child's weight as a concern; b) the clinician then elicits psychosocial, biomedical, and behavioral information to diagnose the origin of the obesity in terms of genetics, lifestyle, emotional dependence, or medical factors; for example, the child may be labeled an "emotional overeater", a "too comfortable child" (parental limit-setting should be practiced), or a "too uncomfortable child" (parent's nurturing should be strengthened); c) the clinician then performs a routine physical. The end result is a report for the parent and a report for the provider. The program would lastly utilize workbooks and parent guides to treat the psychosocial and biological components of the child's obesity in a developmentally-conscious way.22 The duration of care in this fashion can range from three months to several years.22 Participation in the SHAPEDOWN method has been associated with significant improvements in relative weight, weight-related behavior, depression, and knowledge, and was recognized by the American Medical Association in 1988 as an exemplary program.22
However, this method may prove too time-consuming for busy clinicians and providers may not be trained in the program's utilization or aware of its benefits.
Frequent patient visits are required to adequately treat obesity. A two-year
study conducted in Brazil found that the best predictors of positive outcomes
in treating obesity were a higher frequency of physician visits and shorter
intervals between the visits.23 This study also revealed that dietetic counseling
based on small, permanent modifications in eating habits would be effective
in controlling weight gain in the long run.23
Though very few approaches suggested by experts for pediatric obesity are evidence-based, health professionals from many specialties have come together to form medical guidelines for treating childhood obesity.24 Guidelines suggest that clinicians should see patients as frequently as every two weeks when treating obesity.24 Part of coming up with a successful intervention then is simply developing a working model in which obesity is viewed as a chronic disease, in which a patient is treated with respect and praise for even small improvements, and in which doctors know ahead of time that working with obese patients will take time and patience. The experts also suggest that clinicians' language be sensitive and non-accusatory and that if a patient or the parent does not seem "ready" for obesity treatment that he or she not be put on treatment. A negative experience of failure before one is actually ready to make behavioral changes could lead to the belief that one is destined to fail in the future, as well, and could be detrimental to self-esteem.24 According to expert recommendations for treating obesity in children, if a doctor does not have the time to treat an obese patient frequently with continuous monitoring then the patient should be sent elsewhere for treatment.24
The goals for treating obesity should be aimed at medical management, behavioral changes, and weight control.24 Children and their families need to be reminded that weight control will lead to overall health. They need support in gaining skills as a family which will aid in weight control, and in becoming aware of the behaviors which have contributed to obesity in the first place. The health care provider can make suggestions for instituting small, permanent changes, rather than drastic changes, and that the patient work first on maintaining current weight rather than losing weight, since children's natural growth patterns will often help them to overcome obesity.24 Sedentary behaviors such as TV watching should be limited to 1-2 hours per day. Families should be taught to eat well when dining out, and daily activity should be encouraged in children as they will then be more likely to continue in physical activity.24 This is a holistic approach to health and should be explained as a process rather than a one-time event.
More research in this arena is greatly needed. Few studies of long-term weight control in children exist.24 There is also a shortage of controlled studies examining the influence of exercise in treating pediatric obesity.25 No model of treatment will be complete without a sound clinical trial of considerable length to back up what the experts are currently recommending as proper intervention.
Research is also needed to assess effective clinician roles in obesity management and to support the development of evidence-based physician guidelines.14 In one study published in 1997, it was reported that physicians in the Netherlands seek nutrition guidance from dieticians (72%) and from the literature (34%).26 Another study revealed clinicians' inability to obtain obesity materials because of cost or being unsure of the sources was a barrier to their treatment of obesity.27 The same study reported that doctors requested wellness and nutrition materials in the form of one-page, printed handouts.27 Clearly, clinicians are struggling to give the best treatment possible in a short period of time and providing them with clinically-proven guidelines and materials should be a national priority in the fight against obesity.
Probably the most significant "finding" of this review of the literature on pediatric obesity is that there is a paucity of evidence-based research on effective interventions. The existing research has found that most methods of weight loss are unsuccessful over time.6 The take-home message from the few experimental studies of pediatric obesity that exist is that prevention is clearly the best way to deal with pediatric obesity. Prevention should begin as early as possible. In fact, one study revealed that when a general practitioner gave healthy eating advice to pregnant women and their children, it restricted the rate of obesity to 2% compared to levels of 8% in those who did not receive advice.20 Prevention should start with proper training in terms of breastfeeding, weaning, and diets for toddlers.20
Children nine years old and younger may have the most to gain from primary obesity prevention, but little is being done in the health care system, the school system or in the community to push the message of obesity prevention.2 Population-based approaches to the prevention of obesity, like those aimed at smoking prevention, may prove to be the most effective method for creating a significant change in trends of obesity in children, but the experiment still remains to be done.7
The literature also makes it clear that different ethnic groups have different ideals and concepts of attractiveness and beauty, and that this should be considered when designing interventions aimed at obesity prevention.9 For example, it should not be assumed that every adolescent wants to be the smallest size genetically possible. One study reported that African American women are not concerned with looking sexy for men (inferring that white women may stay in shape for this reason), and that they prefer to be full-figured and healthy.9
All available evidence points to the fact that families must be included in childhood treatment of obesity. If an alliance is not developed with a family, family members may be defensive and hesitant to talk about obesity. Clinicians should obtain a history for the whole family of both active and sedentary behaviors.28 Behaviors will not change unless the family is comfortable talking openly about it.29 Family participation is key especially with children still young enough to tend to model parents' behavior rather than peer behavior.19 It has been reported that using open-ended questions, "overweight" instead of "obese", treating parents at the same time, using positive reinforcement, concentrating on the parent who controls the food preparation, using contractual agreements between parents and children, and emphasizing family participation in physical activities will all aid in the treatment of obesity in children.29 If a child is not being supported in his or her efforts at home, the clinician will be at a serious disadvantage in maintaining any control over the necessary intervention.
Changing the trend of childhood obesity is truly a laudable effort for many reasons. One study reported that initial success in pediatric weight loss was associated with long-term favorable changes in the serum-lipid profile, and also reduced hyperinsulinemia.18 It has also been reported that successful weight loss in children contributes to overall improvements in "total problems" and psychological health.30 Clearly, weight loss in children is more successful than in adults over the long-term, and the health benefits of preventing adult obesity are enormous. The future may see more group models of treatment attempted in clinical settings, as suggested in one study, for treating pediatric obesity in a time-deficient setting.1 Additionally, the amelioration of reimbursement problems will probably be successful when managed care and private insurance companies come to realize that they will be saving money in the long-term by treating obesity in its earliest stages. Treating obesity in small steps with family support should lead the way to finding working and long-term solutions to the growing epidemic.
1. Dietz, W., Nelson, A. Barriers to the treatment of childhood obesity: a call to action. J Pediatr. 134:535-6. May 1999.
2. Goran, M. Metabolic precursors and effects of obesity in children: a decade of progress, 1990-1994. Amer J of Clinical Nutr. 73:2, 158-171. Feb 2001.
3. More American teens are overweight. Nat Center for Health Stats. http://www.cdc.gov. March, 2001.
4. Mei, Z., Scanlon, K., et. al. Increasing prevalence of overweight among US low-income preschool children: CDC's pediatric nutrition surveillance 1983-1995. Pediatrics. 101:1, e12. Jan. 1998.
5. Schonfeld-Warden, N., Warden, C. Pediatric obesity: an overview of etiology and treatment. Ped Endocrin. 44:2, 339-354. 1997.
6. Update: prevalence of overweight among children, adolescents, and adults-United States, 1988-1994. MMWR Weekly. 46:9, 199-202. March, 1997.
7. Power, C., Lake, J., Cole, T. Measurement and long-term health risks of child and adolescent fatness. Inter J of Obesity. 21:507-526. 1997.
8. Morbidity and mortality associated with elevated body weight in children and adolescents. Amer Soc for Clin Nutr. 63:445s-7s. 1996.
9. Urgo, M. New obesity guidelines: minority women at risk. Closing the Gap. 6-7. June/July 1998.
10. CDC's guidelines for school and community programs: promoting lifelong physical activity. http://www.cdc.gov. Oct 2000.
11. Keller, C., Stevens, K. Childhood obesity: measurement and risk assessment. Ped Nursing. 22:6, 494-498. Dec 1996.
12. Romanella, N., Wakat, D., Loyd, B., Kelly, L. Physical activity and attitudes in lean and obese children and their mothers. Inter J of Obesity. 15:407-414. 1991.
13. Morton, J., Guthrie, J. Changes in children's total fat intakes and their food group sources of fat, 1989-91 versus 1994-95: implications for diet quality. Fam Econ & Nutr Review. 11:3. 44-57. 1998.
14. Kristeller, J., Hoerr, R. Physician attitudes toward managing obesity: differences among six specialty groups. Preventive Med. 26:542-9. 1997.
15. Hoppe, R., Ogden, J. Practice nurses' beliefs about obesity and weight related interventions in primary care. Inter J of Obesity. 21:141-146. 1997.
16. Logue, E., Gilchrist, V., Bourguet, C., Bartos, P. Recognition and management of obesity in a family practice setting. JABFP. 6:5, 457-462. Sept-Oct 1993.
17. Lewis, B., Montes, S., Illige-Saucier, M. A pilot study examining patient response to a weight loss workbook designed to be used in a family medicine outpatient setting. Arch Fam Med. 9:759-764. Aug 2000.
18. Nuutinen, O., Knip, M. Long-term weight control in obese children: persistence of treatment outcome and metabolic changes. Inter J of Obesity. 16:279-287. 1992.
19. American Dietetic Association. Behaviorally focused nutrition education programs for children. J of Amer Diet Assoc. 99:11, 7. Nov 1999.
20. Gill, T. Key issues in the prevention of obesity. British Med Bulletin. 53:2, 359-388. 1997.
21. Epstein, L. Family based behavioral intervention for obese children. Int J Obes Relat Metab Disord. 20 Suppl. 1:S14-21. 1996.
22. Mellin, L., Frost, L. Child and adolescent obesity: the nurse practitioner's use of the SHAPEDOWN method. J of Ped Health Care. 6:187-93. 1992.
23. Valverde, M., Patin, R., et. al. Outcomes of obese children and adolescents enrolled in a multidisciplinary health program. Inter J of Obesity. 22:513-519. 1998.
24. Barlow, S., Dietz, W. Obesity evaluation and treatment: expert committee recommendations. Pediatrics. 102:3. Sept 1998.
25. Epstein, L., Coleman, K., Myers, M. Exercise in treating obesity in children and adolescents. Med & Sci in Sports & Exer. 28:4, 428-435. 1996.
26. Hiddink, G., Hautvast, J., et. al. Information sources and strategies of nutrition guidance used by primary care physicians. Am J Clin Nutr. 65:1996S-2003S. 1997.
27. Moore Kenner, M., Taylor, M., et. al. Primary care providers need a variety of nutrition and wellness patient education materials. J of Amer Diet Assoc. 99:4, 462-466. April 1999.
28. Bronfin, D., Urbina, E. The role of the pediatrician in the promotion of cardiovascular health. Amer J of Med Sci. 310:S42-46. Dec 1995.
29. AACE/ACE position statement on the prevention, diagnosis, and treatment of obesity. Amer Assoc of Clin Endocrin. National Guideline Clearinghouse. 1998.
30. Myers, M., Raynor, H., Epstein, L. Predictors of child psychological changes during family based treatment for obesity. Arch Ped Adol Med. 152. 1998.
Jennifer McCarthy conducts health research for the University of Florida's Dept. of Community Health & Family Medicine and for the College of Medicine's Women's Health Research Center. Mary Ann Burg was Research Director of the Dept. of Community Health & Family Medicine until Fall 2001 and is currently Executive Director for the College of Medicine's Women's Health Research Center at UF. Kristen Smith is the Assistant Director of the MPH program at UF and conducts health research for the Dept. of Health Policy and Epidemiology. Cathy Burns is the Project Co-ordinator for Research out of the Dept. of Community Health & Family Medicine at University of Florida.
Copyright Priory Lodge Education Ltd (Publishers) 2002