Presentation of obesity may range from asymptomatic to presentation complicated by multiple comorbidities, including cancer, coronary artery disease, diabetes, hypertension, gout, obstructive sleep apnea, and osteoarthritis. Worldwide, it is estimated that nearly 4 million people die each year as a consequence of weight-related comorbidities.
The definitive test for obesity remains the body mass index (BMI; obesity is defined as a BMI ≥30 kg/m²).
Central or abdominal obesity has a stronger association with obesity-related comorbidity than peripheral (i.e., subcutaneous) obesity, so waist circumference may be a better indicator of the risk for obesity-related comorbidity than BMI.
The mainstay of nonsurgical treatment of obesity is diet and exercise, with psychological therapy as a recommended adjunct for all patients. However, the overall efficacy and durability of this combination is poor, and the management of obesity is evolving with new pharmacologic options and improved surgical outcomes.
Pharmacotherapy may be considered as an adjunct to diet and exercise (preferably not as monotherapy) for patients with a BMI ≥30 kg/m².
Surgical treatment is an option for patients with more severe obesity, or for those who do not achieve substantial durable weight loss or comorbidity improvement with nonsurgical management. Potential complications are numerous, but have declined in recent decades. Studies indicate that surgical treatment is more effective for severe obesity than nonsurgical treatment.
Obesity can be defined as a chronic condition due to an excess amount of body fat. While there are many methods to determine the relative amount of body fat, the most widely used method to diagnose obesity is the body mass index, defined as weight divided by height squared ([weight in kg]/[height in m]²). See Classification.
History and exam
Key diagnostic factors
Other diagnostic factors
- waist circumference
- comorbid conditions
- age ≥40 years
- peri- and postmenopause
- prior pregnancy
- marital status
- sleep deprivation
- education level
- poor in utero nutrition
- socioeconomic status
- sedentary lifestyle
- television watching or video gaming
- diet high in sugar, cholesterol, fat, and fast food
- heavy alcohol intake
- binge-eating disorder
- night eating syndrome
- leptin deficiency
- corticosteroid therapy
- antidepressant therapy
- antipsychotic therapy
- beta-blocker therapy
- adjuvant breast cancer therapy
- psychiatric diagnosis
1st investigations to order
- clinical exam
Investigations to consider
- serum aminotransferases
- thyroid function tests
- abdominal ultrasound scan
- polysomnography (sleep study)
BMI ≥30 kg/m²; or else BMI ≥27 kg/m² with an obesity-related comorbidity
BMI ≥35 kg/m² with or without comorbidities
- Hypothyroidism, primary
- Hypothyroidism, central
- Cushing syndrome
- 2022 ASMBS and IFSO: indications for metabolic and bariatric surgery
- AGA clinical practice guideline on pharmacological interventions for adults with obesity
Obesity - diet and exercise
Obesity - drugs and surgeryMore Patient leaflets
Body Mass Index (Quetelet's index)More Calculators
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