Summary
Definition
History and exam
Key diagnostic factors
- height
- weight
Other diagnostic factors
- waist circumference
- comorbid conditions
Risk factors
- hypothyroidism
- hypercortisolism
- age ≥40 years
- peri- and postmenopause
- prior pregnancy
- married
- sleep deprivation
- history of tobacco smoking
- less formal education
- poor in utero nutrition
- low socioeconomic status
- sedentary lifestyle
- television watching and video games >2 to 3 hours daily
- diet high in sugar, cholesterol, fat, and fast food
- heavy alcohol intake (>2 drinks per day)
- binge-eating disorder
- night eating syndrome
- leptin deficiency
- corticosteroid therapy
- antidepressant therapy
- antipsychotic therapy
- beta-blocker therapy
- adjuvant breast cancer therapy
- psychiatric diagnosis
Diagnostic investigations
1st investigations to order
- clinical exam
Investigations to consider
- FBC
- serum transaminases
- thyroid function tests
- ECG
- abdominal ultrasound scan
- polysomnography (sleep study)
Treatment algorithm
BMI ≥30 kg/m²; or else BMI ≥27 kg/m² with an obesity-related comorbidity
BMI ≥40 kg/m²; or else BMI ≥35 kg/m² with significant comorbidities and dietary attempts at weight control have been ineffective
Contributors
Authors
Constantine T. Frantzides, MD, PhD, FACS

Director, Chicago Institute of Minimally Invasive Surgery (CIMIS)
Director, Laparoscopic and Bariatric Fellowship Program
Clinical Professor of Surgery, University of Illinois
Chicago
IL
Disclosures
CTF declares that he has no competing interests.
Mark A. Carlson, MD, FACS

Professor, Department of Surgery
Professor, Department of Genetics, Cell Biology and Anatomy (courtesy)
Director, Center for Advanced Surgical Technology (CAST)
University of Nebraska Medical Center
Staff Physician, Surgery Department
Omaha VA Medical Center
Omaha
NE
Disclosures
MAC declares that he has no competing interests.
Kelsey R. Tieken, MD

General Surgery Resident
University of Nebraska Medical Center
Omaha
NE
Disclosures
KRT declares that she has no competing interests.
Acknowledgements
Dr Constantine T. Frantzides, Dr Mark A. Carlson, and Dr Kelsey R. Tieken would like to gratefully acknowledge Dr Minh B. Luu and Dr Scott N. Welle, previous contributors to this topic.
Disclosures
MBL and SNW declare that they have no competing interests.
Peer reviewers
Carel Le Roux, MRCP, PhD, FRCPath
Consultant in Metabolic Medicine
Imperial College London
Charing Cross Hospital
London
UK
Disclosures
CLR declares that he has no competing interests.
Arya M. Sharma, MD, PhD, FRCPC
Professor of Medicine
Chair for Obesity Research & Management
University of Alberta
Royal Alexandra Hospital
Edmonton
Canada
Disclosures
AMS declares that he has no competing interests.
Edward H. Livingston, MD, FACS
Chair in Surgery
Division of Gastrointestinal and Endocrine Surgery
University of Texas
Southwestern Medical Center
Dallas
TX
Disclosures
EHL declares that he has no competing interests.
Differentials
- Hypothyroidism, primary
- Hypothyroidism, central
- Cushing's syndrome
More DifferentialsGuidelines
- Obesity: identification, assessment and management
- AGA clinical practice guidelines on intragastric balloons in the management of obesity
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Obesity - diet and exercise
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