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EVIDENCE-STATEMENT:
OBESITY (Screening and Counseling)
Why This Chapter is
• Obesity is epidemic in the United States. Between 1976 to 1980 and 1999 to Important for
2002, the proportion of adults classified as obese doubled. During that period, Employers:
the proportion of children (aged 6 to 11 years) classified as overweight doubled An Overview
and the proportion of overweight adolescents (aged 12 to 19 years) tripled.1 • Nearly 80% of obese adults suffer from diabetes, high blood pressure, coronary artery disease, high cholesterol, osteoarthritis, or a combination of theseconditions.2 • Because it contributes to so many other serious conditions, obesity is considered to be one of the most important, underlying, and preventablecauses of poor health and premature death.3 • Obesity contributes significantly to medical costs in the United States.4• The cost to employers of obesity-related health problems in 1994 was estimated to be $13 billion per year, including $8 billion in medical claims,$2.4 billion in paid sick leave, $1.8 billion in life insurance, and almost $1billion in disability insurance.5 • Each year, an estimated 39 million work days are lost to obesity-related • For adults, losing excess weight has positive effects on overall health status. A 5% to 7% reduction in body weight decreases the risk of type 2 diabetes,reduces blood pressures, and improves lipid profiles.7 Among patients withexisting glucose intolerance, weight loss through lifestyle change is associatedwith as much as a 58% reduction in incidence of diabetes.8 Clinical Preventive Service Recommendations
U.S. Preventive
The U.S. Preventive Services Task Force (USPSTF) recommends that clinicians Services Task Force
screen all adult patients for obesity and offer intensive counseling and behavioral Recommendation
interventions to promote sustained weight loss for obese adults.9 Evidence Rating: B
The USPSTF found good evidence that body mass index (BMI), calculated as (Recommended/At
weight in kilograms divided by height in meters squared, is reliable and valid for Least Fair Evidence)
identifying adults at increased risk for mortality and morbidity due to overweightand obesity. There is fair to good evidence that high-intensity counseling —about diet, exercise, or both — together with behavioral interventions aimed atskill development, motivation, and support strategies produces modest, sustainedweight loss (typically 3 to 5 kg for 1 year or more) in adults who are obese (asdefined by BMI Ͼ 30 kg/m2). Although the USPSTF did not find directevidence that behavioral interventions lower mortality or morbidity from obesity,the USPSTF concluded that changes in intermediate outcomes, such as improvedglucose metabolism, lipid levels, and blood pressure, from modest weight lossprovide indirect evidence of health benefits.9 EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
Other Evidence-
The FDA has approved two medications for the treatment of obesity that can Based Research
reduce patient weight by an average of 2.6 to 4.8 kg (5.7 to 10.6 lbs) for at least Food and Drug
2 years: orlistat (Xenical®) and sibutramine (Meridia®).10-11 Administration (FDA)
Evidence Rating:
Recommended
The NHLBI recommends that surgical procedures for obese patients be reserved Guidance
for patients with class III obesity (BMI Ͼ 40) and patients with class II obesity The National Heart,
(BMI of 35 to 39.9) who also have at least one obesity-related illness.12 Lung, and Blood
Institute (NHLBI)
Evidence Rating:
Information Sources
The recommendations and supporting information contained in this documentcame from several sources, including the: • American Academy of Bariatric Surgery• American Academy of Family Physicians (AAFP)• American Academy of Pediatrics (AAP)• American Medical Association (AMA)• Food and Drug Administration (FDA)• National Academy of Sciences, Institute of Medicine (IOM)• National Center for Education in Maternal and Child Health• National Heart, Lung, Blood Institute (NHLBI)• Peer-reviewed research• U.S. Department of Health and Human Services• U.S. Preventive Services Task Force (USPSTF) The background and supporting information in this document is based on acompilation of research findings. All of the information presented in thisdocument should be attributed to its referenced source and should not beconsidered a reflection of the opinions of other organizations cited in the text. Condition/Disease-Specific Information
Epidemiology of
The Body Mass Index (BMI) is widely used as an index of body composition and Condition/Disease
weight. BMI’s in the range of 18.5 to 24.9 are generally considered to be optimalfor adults. “Underweight” is generally defined as a BMI less than 18.5,“overweight” as BMI between 25 to 29.9, and “obesity” as a BMI greater than30. Age- and gender-specific standards also exist for children and adolescents thattake into account the changes in body composition that occur as children grow(See “Other Important Information,” below).
Obesity is epidemic in the United States. Between 1976 to 1980 and 1999 to2002, the proportion of adults classified as obese doubled.1 Nearly 80% of obese EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
adults suffer from diabetes, high blood pressure, coronary artery disease, highcholesterol, osteoarthritis, or a combination of these conditions.2 Research hasalso documented that obesity is associated with decreased quality of life.13 During this period, the proportion of children (aged 6 to 11 years) classified asoverweight doubled and the proportion of overweight adolescents (aged 12 to 19 years) tripled.1 The complications of being overweight are particularly severefor children due to the years of life they are at risking of losing as a result ofearly-onset chronic diseases, such as diabetes14 and cardiovascular disease.15 For adults, losing excess weight has positive effects on overall health status. A 5%to 7% reduction in body weight decreases the risk of type 2 diabetes, reducesblood pressures, and improves lipid profiles.7 Among patients with existingglucose intolerance, weight loss through lifestyle change is associated with asmuch as a 58% reduction in incidence of diabetes.8 The USPSTF found limiteddata on the positive effect that weight loss may have on overall mortality, mentalhealth, and daily functioning.9 Condition/Disease
Obesity is more common among adult women, Native Americans, African- Risk Factors
Americans, Native Hawaiians, and Hispanics than other populations.7 Value of Prevention
Economic Burden of
Obesity contributes significantly to medical costs in the United States. In 1998, Condition/Disease
9.1% of total annual medical expenditures could be attributed to obesity.4Between 1987 and 2001, 27% of the growth in inflation-adjusted per-capitahealthcare spending was associated with obesity.6 The annual cost of obesity isestimated to range from $69 billion to $117 billion (including $61 billion fordirect medical expenses and $56 billion for indirect expenses such as lostproductivity [in year 2000 dollars]).16 The expected lifetime costs of cardiovascular disease (including coronary heartdisease, heart attack, and stroke) increase by 20% with mild obesity (class I: BMIof 30 to 34.9), 50% with moderate obesity (class II: BMI of 35 to 39.9), andnearly 200% with severe obesity (class III: BMI of 40 or higher).5 One largehealth plan found that its yearly total medical claims were 18% higher foroverweight individuals and 32% higher for obese than for healthy-weightindividuals.17 A 2001 study found obese adults had, on average, about 37% higher healthcareexpenses per person than normal-weight adults. This excess expense increasedprivate healthcare spending by nearly 12% (more than $36 billion).6 Workplace Burden of
The cost to employers of obesity-related health problems in 1994 was estimated Condition/Disease
to be $13 billion per year, including $8 billion in medical claims, $2.4 billion inpaid sick leave, $1.8 billion in life insurance, and almost $1 billion in disabilityinsurance.5 EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
Obesity and related illnesses are also a major cause of disability. Each year, anestimated 39 million work days are lost to obesity-related illnesses.6 Economic Benefit of
Nutrition education, diet, and exercise counseling are effective interventions for Preventive
obesity prevention and have the potential to significantly reduce the direct and Intervention
indirect costs of obesity-related illnesses. Researchers have estimated that even amodest reduction of 10% in body weight in an obese individual might reducethe expected lifetime healthcare costs of major obesity-related diseases for theindividual by $2,200 to $5,300, depending on age, sex, and initial BMI.18 Estimated Cost of
The cost of BMI screening is negligible when height and weight measurements Preventive
are already recorded as part of a routine physical exam. In 2004, the private- Intervention
sector cost of obesity counseling averaged $39 per session; approximately 95% ofall paid claims fell within the range of $0 to $129 per session.19 Estimated Cost of
In the United States, the costs associated with treating obesity vary by location, Treatment
provider type, and treatment modality. For example, in 2006 the average wholesaleprice of a 1-month supply of pharmacological therapy for obesity was $207.04 fororlistat (Xenical“) (120 mg three times daily) and $423.60 for a 3-month supply ofsibutramine (Meridia“) (15 mg daily).28 In contrast, the average price of a surgicalprocedure for obesity in 2004 ranged from $20,000 to $35,000.21 Cost-Effectiveness
The cost-effectiveness of screening for and treating obesity is unclear. Because and/or Cost-Benefit
obese individuals are at risk for serious and costly complications, such as diabetes Analysis of
and cardiovascular disease, screening for obesity and early intervention to reduce Preventive
excess weight could improve lives and increase the cost-effectiveness of healthcare Intervention
dollars. However, few studies have tested the cost-effectiveness of screening forand treating obesity in the United States, although several cost-effectivenessstudies have been conducted in England, Australia, and Northern Europe. Thestudies conducted abroad applied their-effectiveness analyses to morbidly obesepatients (i.e., persons with BMIs Ն 40, which is approximately 100 pounds overnormal weight for a typical person). The studies found that a range ofinterventions (such as pharmacotherapy, surgery, and intensive diet andbehavioral therapy) can be inexpensive or even cost-saving, depending on thepopulation’s risk and the interventions used.22 These results cannot be generalizedto patients who are not morbidly obese. Further, the results may not begeneralizable to the U.S. population because of differences between thepopulations studied and the U.S. population and differences in healthcare systemfunding and delivery mechanisms in the countries studied.
Preventive Intervention Information
Preventive
Because obesity is a modifiable major risk factor for several serious conditions, Intervention:
screening for obesity and treating it successfully can be expected to produce Purpose of Screening
significant health benefits. Screening for obesity allows clinicians to identify and Counseling
patients at risk and begin treatment before serious weight-related complicationsoccur. Unfortunately, weight is frequently overlooked in primary care practice;only 42% of obese patients report receiving advice to lose weight during aroutine check-up in the previous year.23 EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
Benefits and Risks
Although the USPSTF did not find direct evidence that behavioral interventions of Intervention
lower mortality or morbidity from obesity, the USPSTF concluded that changesin intermediate outcomes, such as improved glucose metabolism, lipid levels, andblood pressure, from modest weight loss provide indirect evidence of healthbenefits.9 The USPSTF was unable to find studies that suggested harms associated withscreening or counseling obese patients.24 However, the USPSTF notes thatbecause obesity carries a stigma, there is a potential risk in labeling patients asobese. The USPSTF found evidence that dieting among overweight and obeseadults does not lead to problems in psychological functioning or eating disorders.
However, the USPSTF notes that the evidence is limited and conflicting on theharms of weight cycling (losing and then regaining a large amount of weight). Inaddition, the USPSTF notes that some forms of treatment, specificallypharmacological therapy and surgical intervention, carry potential harm.24 The USPSTF concluded that the benefits of screening and behavioralinterventions outweigh potential harms.
Initiation, Cessation,
The USPSTF did not find evidence to determine the optimal times for the and Interval
initiation, cessation, or interval of obesity screening. Several health organizations, Screening
including the American Academy of Family Physicians (AAFP),25 the AmericanHeart Association (AHA),26 and the American College of Preventive Medicine(ACPM),27 agree on the importance of screening for obesity and recommendperiodically measuring the height and weight of all patients. Some authoritieshave recommended that height and weight be recorded and BMIs calculated atevery healthcare visit. Counseling
High-intensity counseling is defined by the USPSTF as 2 or more person-to-person sessions per month for at least the first 3 months of treatment for a totalof 6 counseling sessions per calendar year.
Intervention Process
The USPSTF notes that the most effective interventions for obesity combinenutrition education, diet and exercise counseling, and behavioral strategies tohelp obese patients acquire the skills they need to successfully change their eatinghabits and to become more physically active.9 Screening
The preferred method of screening an adult patient for obesity is to measure theirbody-mass index (BMI). This is a reliable and valid measurement of adult weightstatus. BMI is defined as weight in pounds divided by height in inches squaredand multiplied by 703, or as weight in kilograms divided by height in meterssquared. BMI charts provide completed calculations and can be used todetermine BMI by simply entering weight and height. The following definitionsfrom the Clinical Guidelines on the Identification, Evaluation, and Treatment ofOverweight and Obesity in Adults12 should be used to classify weight status: Screening for obesity may also include measurement of waist circumferencebecause central adiposity (excess fat around the middle) can also increase anindividual’s risk of developing cardiovascular disease. A waist circumference EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
greater than 102 centimeters for men and 88 centimeters for women is associatedwith an increased risk of cardiovascular disease. However, waist measurements arenot reliable indicators of cardiovascular disease risk in obese patients with a BMIof 35 or above.24 BMI Chart for Adults
Classification
Counseling and
The most effective behavioral interventions for obesity combine nutrition Treatment
education, diet and exercise counseling, and behavioral strategies to help obese Information
patients acquire the skills they need to change their eating habits and becomemore physically active.28 Clinicians should offer a treatment plan of intensive counseling and behavioralinterventions to obese patients. Intensive counseling is defined as 2 or moreperson-to-person individual or group sessions per month for at least 3 months.24If clinicians are unable to offer obese patients intensive counseling and behavioralinterventions, they should refer patients to a program or provider that can offerthese services. However, this should not undermine the existing patient-physicianrelationship because research has shown that clinicians’ advice plays a role inmany health outcomes.29-30 No evidence exists to show that one counseling method is better than another forobese patients. Clinicians must therefore use their own judgment to select anappropriate counseling method for a given patient. The “5-A” framework31 that isused for smoking cessation counseling might be useful for the initial evaluationand counseling of an obese patient and might be helpful in broaching the subjectof weight loss with patients: • Assess the patient’s weight by measuring his or her BMI and waist and evaluate
the patient’s factors that affect choice of behavior change goals/methods.
• Advise the patient to lose weight through physical activity and a healthy diet
using clear, specific, and personalized messages.
• Agree with the patient on specific changes he or she can make to reach his or
• Assist the patient in making changes by offering support services, education,
• Arrange for follow-up and support services.
Experts recommend that pharmacological therapy for obesity, such asmedications that induce weight loss or suppress appetite, only be used as part of a EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
treatment plan that also includes lifestyle modifications such as intensive diet,exercise, and behavioral counseling.9 The Food and Drug Administration (FDA)has approved two medications for the treatment of obesity that can reducepatient weight by an average of 2.6 to 4.8 kg (5.7 to 10.6 lbs) for at least 2 years:orlistat (Xenical®) and sibutramine (Meridia®).10-11 While these drugs are effective,they may produce unwanted side effects and few data are available on the safetyof their long-term use. The National Heart, Lung, and Blood Institute (NHLBI) recommends thatsurgical procedures be reserved for obese patients with class III obesity (BMIgreater than 40) and patients with class II obesity (BMI of 35 to 39.9) who haveat least one obesity-related illness. Surgical procedures, such as bariatric surgery,are effective for treating obesity in the short-term (on average, extremely obesepatients lose 10 to 159 kg [22 to 349.8 lbs] in 1 to 5 years).12 Bariatric surgery produces improvements in health for most of the patients. Forexample, a meta-analysis of bariatric surgery studies found that 60% to 70% ofpatients lost all of their excess weight and that diabetes was brought undercontrol in almost 77% of patients who had had diabetes prior to the surgery.32Although the long-term health effects of surgery for obesity are not wellcharacterized, surgical cohort studies suggest that large amounts of weight lossmay be linked to dramatic improvements in glucose metabolism. In addition,some evidence indicates that surgically treated patients are more likely to haveresolution of diabetes, hypertension, and certain lipid disorders than patients whodo not undergo surgery.28 However, bariatric surgery is associated with serious risks, including the risk ofdeath, and 25% of patients may need a second operation within 5 years.28 Other Important Information
The USPSTF concluded that the evidence was insufficient to recommend for oragainst routine screening for overweight in children and adolescents as a means toprevent adverse health outcomes.33 The USPSTF found 1) fair evidence that BMI is a reasonable measure foridentifying children and adolescents who are overweight or are at risk forbecoming overweight, 2) fair evidence that overweight adolescents and children(Ն 8 years old)are at increased risk for becoming obese adults, 3) insufficientevidence for the effectiveness of behavioral counseling or other preventiveinterventions with overweight children and adolescents that can be conducted inprimary care settings or to which primary care clinicians can make referrals, and4) insufficient evidence to ascertain the magnitude of the potential harms ofscreening or prevention and treatment interventions. The USPSTF was unable todetermine the balance between potential benefits and harms of routine screeningof children and adolescents for overweight.
Although the USPSTF found insufficient evidence to recommend for or againstscreening children and adolescents for overweight, many health organizations EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
have created guidelines for this type of screening. For example, the AmericanAcademy of Family Physicians (AAFP),34 American Academy of Pediatrics(AAP),35 National Center for Education in Maternal and Child Health,36 andAmerican Medical Association (AMA) have developed guidelines that includerecommendations for measuring height and weight as part of periodic healthexaminations for children and adolescents. In 2003, the AAP published a policy statement on the prevention of pediatricoverweight and obesity. In this report, the AAP stated that a BMI between the85th and 95th percentiles for age and sex indicates that the child or adolescent isat risk for overweight and a BMI at or above the 95th percentile indicates thatthe child or adolescent is overweight or obese.35 Because obesity is associated withsignificant health problems in children, the AAP proposed strategies to fosterprevention and early detection of overweight and obesity. In addition to thehealthy nutrition recommendations, the AAP developed a policy statement onactive healthy living for the prevention of childhood obesity.37 According to thispolicy, physicians and other healthcare professionals should advocate for policychanges at the community, state, and national levels to support healthy nutrition,reduce sedentary time, and increase physical activity levels in children andadolescents while providing education and supervision of the child’s health on theimportance of regular physical activity and reduced sedentary time to families. Strength of Evidence for the Clinical Preventive Service
The level of evidence supporting the recommendations contained in this
chapter is described below.
Evidence-Based Research:
U.S. Preventive Services Task Force (USPSTF) Strength of evidence: B (Recommended/At Least Fair Evidence) • The USPSTF found fair to good evidence to support screening all adult patients for obesity and offering intensive counseling and behavioralinterventions to promote sustained weight loss for obese adults.9 Food and Drug Administration (FDA)Strength of Evidence: Clinical Trials The FDA has approved two medications for the treatment of obesity that canreduce patient weight by an average of 2.6 to 4.8 kg (5.7 to 10.6 lbs) for at least2 years: orlistat (Xenical®) and sibutramine (Meridia®).10-11 Recommended Guidance::
The National Heart, Lung, and Blood Institute (NHLBI) Strength of evidence: Not Specified• The NHLBI recommends that surgical procedures for obese patients be reserved for patients with class III obesity (BMI Ͼ40) and patients with classII obesity (BMI of 35 to 39.9) who also have at least one obesity-relatedillness.12 EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
Authored by:
Tohill BC, Campbell KP, Chattopadhyay S. Obesity evidence-statement: screening, counseling, and treatment. In: Campbell KP, Lanza A, Dixon R, Chattopadhyay S, Molinari N, Finch RA, editors.
A Purchaser’s Guide to Clinical Preventive Services: Moving Science into Coverage. Washington, DC:National Business Group on Health; 2006.
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9. U.S. Preventive Services Task Force. Guide to Clinical Preventive Services. 3rd ed. Rockville, MD: Agency for Health Care 10. Food and Drug Administration. FDA approves orilstat for obesity. FDA Talk Paper. [cited 2006 Oct 21]. Available from: http://www.fda.gov/bbs/topics/ANSWERS/ANS00951.html. 11. Food and Drug Administration. FDA approves sibutramine to treat obesity. FDA Talk Paper. [cited 2006 Oct 21]. Available from: http://www.fda.gov/bbs/topics/ANSWERS/ANS00835.html. 12. National Heart, Lung, and Blood Institute. Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. Available from: http:/www.nhlbi.nih.gov/guidelines/obesity/ob_gdlns.htm. 13. Livingston EH, Fink AS. Quality of life: cost and future of bariatric surgery. Arch Surg 2003;138:383-8.
14. Ludwig DS, Ebbeling CB. Type 2 diabetes mellitus in children, primary care and public health considerations. JAMA 15. Must A, Jacques PF, Dallal GE, Bajema CJ, Dietz WH. Long-term morbidity and mortality of overweight adolescents. A follow-up of the Harvard Growth Study of 1922 to 1935. N Engl J Med 1992;327:1350-5.
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17. Kaiser Network. Blue Cross and Blue Shield of North Carolina introduces benefits package featuring obesity treatments.
Kaiser Daily Health Policy Report, 2004. Available from:http://www.kaisernetwork.org/daily_reports/rep_index.cfm?hint=3&DR_ID=26217. EVIDENCE-STATEMENT: Obesity (Screening and Counseling)
18. Oster G, Thompson D, Edelsberg J, Bird AP, Colditz GA. Lifetime health and economic benefits of weight loss among obese persons. Am J Public Health 1999;89:1536-42.
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Leawood (KS): American Academy of Family Physicians; 2005. 26. Klein S, Burke LE, Bray GA, Blair S, Allison DB, Pi-Sunyer X, et al. Clinical implications of obesity with specific focus on cardiovascular disease: a statement for professionals from the American Heart Association Council on Nutrition, PhysicalActivity, and Metabolism: endorsed by the American College of Cardiology. Circulation 2004;110:2952-67.
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