Upon completion of the chapter, the reader will be able to:
Explain the underlying causes of overweight and obesity.
Identify parameters used to diagnose obesity and other objective information that indicates the severity of disease.
Identify desired therapeutic goals for patients who are overweight or obese.
Recommend appropriate nonpharmacologic and pharmacologic therapeutic interventions for overweight or obese patients.
Implement a monitoring plan that will assess both the efficacy and safety of therapy initiated.
Educate patients about the disease state and associated risks, comprehensive lifestyle interventions, drug therapy, and surgical options necessary for effective treatment.
Overweight and obesity are terms used to describe weight measurements greater than what is considered healthy for a given height.1 KEY CONCEPT Body mass index (BMI), waist circumference (WC), comorbidities, and readiness to lose weight are used in the assessment of overweight or obese patients. The primary modality in defining overweight and obesity is the BMI, a measure of body fat based on height and weight. BMI should be used to identify adults at increased risk for cardiovascular disease (CVD) and other obesity-related disorders. Evaluation of the patient’s risk status involves not only calculation of the BMI but also the measurement of WC and determination of obesity-related comorbidities and presence of CVD risk factors. KEY CONCEPT The presence of comorbidities (CVD, type 2 diabetes mellitus, and sleep apnea) and cardiovascular risk factors (cigarette smoking, hypertension, elevated low-density lipoprotein cholesterol, low high-density lipoprotein cholesterol, impaired fasting glucose) requires identification and aggressive management for overall effective treatment of the overweight or obese patient. Obese patients may be at very high risk for mortality if concomitant risk factors exist; therefore, high-risk patients require aggressive modification of risk factors in addition to obesity treatment.2
ETIOLOGY AND EPIDEMIOLOGY
Obesity is a multifactorial, complex disease that occurs because of an interaction between genotype and the environment. Although the etiology is not completely known, it involves overlapping silos of social, behavioral, and cultural influence; pathophysiology; metabolism; and genetic composition.3 The majority of overweight or obese individuals are adults, but these diseases are also prevalent in children between 2 and 19 years of age. While the prevalence of obesity appears to be leveling off, approximately 35% of US adults 20 years of age and older are currently considered obese. The prevalence of obesity in men and women of various racial and ethnic origins differ. Thirty-six percent of non-Hispanic white adults are considered obese, where approximately 40% of Mexican Americans and 50% of non-Hispanic black Americans are obese.4
Thirty-two percent of children and adolescents aged 2 through 19 years are considered either overweight or obese. The prevalence of obesity among this age group remains unchanged at 17%.5 Overweight children typically mature to overweight adults, but most obese adults were not overweight as children.6 Overweight and obesity, when present in ...