Obesity Microchapters |
Diagnosis |
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Treatment |
Lifestyle Intervention and Counseling (Comprehensive Lifestyle Intervention) |
Case Studies |
USPSTF Recommendations and Guidelines on Management of Obesity |
2017 Guidelines for Screening of Obesity in Children and Adolescents |
AHA/ACC/TOS Guidelines on Management of Overweight and Obesity |
2013 AHA/ACC/TOS Guidelines on Management of Overweight and Obesity |
Obesity screening On the Web |
American Roentgen Ray Society Images of Obesity screening |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2]; Associate Editor(s)-in-Chief: Karol Gema Hernandez, M.D. [3] Usama Talib, BSc, MD [4]
Screening for obesity is recommended among children more than 6 years of age, and at least once a year among adults. Screening strategies include calculation of the body mass index (BMI), measurement of waist circumference, and measurement of body fat.
Screening for obesity should be performed at least once a year among adults. The cut-off values of BMI to define obesity and overweight among adults are as follows:
Clinical practice guidelines and systematic review[1][2] by the United States Preventive Services Task Force in 2010 stated:[3][4]
The review included a meta-analysis of trials of weight management programs and concluded that weighted mean BMI decrease of 2.4 with comprehensive, medium- to high-intensity programs.[2]
BMI does not take into account differing ratios of adipose to lean tissue; nor does it distinguish between differing forms of adiposity, some of which may correlate more closely with cardiovascular risk. Increasing understanding of the biology of different forms of adipose tissue has shown that visceral fat or central obesity (male-type or apple-type obesity) has a much stronger correlation, particularly with cardiovascular disease, than the BMI alone.[5]
The absolute waist circumference (>102 cm in men and >88 cm in women) or waist-hip ratio (>0.9 for men and >0.85 for women)[5] are both used as measures of central obesity.
In a cohort of almost 15,000 subjects from the National Health and Nutrition Examination Survey (NHANES) III study, waist circumference explained obesity-related health risk significantly better than BMI when metabolic syndrome was taken as an outcome measure.[6]
An alternative way to determine obesity is to assess percent body fat. Doctors and scientists generally agree that men with more than 25% body fat and women with more than 30% body fat are obese. However, it is difficult to measure body fat precisely. The most accepted method has been to weigh a person underwater, but underwater weighing is a procedure limited to laboratories with special equipment. Two simpler methods for measuring body fat are the skinfold test, in which a pinch of skin is precisely measured to determine the thickness of the subcutaneous fat layer; or bioelectrical impedance analysis, usually only carried out at specialist clinics. Their routine use is discouraged.[7]
Other measurements of body fat include computed tomography (CT/CAT scan), magnetic resonance imaging (MRI/NMR), and dual energy X-ray absorptiometry (DXA).[8]
Class I |
"1. Measure height and weight and calculate BMI at annual visits or more frequently. (Level of Evidence: E)" |
"2. Use the current cutpoints for overweight (BMI >25.0-29.9 kg/m2) to identify adults who may be at elevated risk of CVD and the current cut points for obesity (BMI≥30) to identify adults who may be at elevated risk of mortality from all causes. (Level of Evidence: A)" |
"3. Advise overweight and obese adults that the greater the BMI, the greater the risk of CVD, type 2 diabetes, and all-cause mortality. (Level of Evidence: A)" |
Class IIa |
"1. Measure waist circumference at annual visits or more frequently in overweight and obese adults. Advise adults that the greater the waist circumference, the greater the risk of CVD, type 2 diabetes, and all-cause mortality. The cutpoints currently in common use (from either NIH/NHLBI or WHO/IDF) may continue to be used to identify patients who may be at increased risk until further evidence becomes available. (Level of Evidence: B)" |
USPSTF Obesity Guidelines for Children and Adolescents 6 years and older |
"1. The USPSTF recommends that clinicians screen for obesity in children and adolescents 6 years and older and offer or refer them to comprehensive, intensive behavioral interventions to promote improvements in weight status.(Recommendation Grade: B)" |
USPSTF Obesity Guidelines for Adults |
"1. The USPSTF recommends screening all adults for obesity. Clinicians should offer or refer patients with a body mass index (BMI) of 30 kg/m2 or higher to intensive, multicomponent behavioral interventions.(Recommendation Grade: B)" |