B P4 C30 Obesity: Medical and Surgical Management Flashcards
A medical perspective defines _____ as excess body fat associated with comorbid conditions and increasing mortality risk.
Obesity
BMI cut off for
Overweight
Obesity
Severe obesity
Overweight - BMI >/= 25kg/m2
Obesity - BMI >/= 30kg/m2
Severe obesity - BMI >/= 40kg/m2 or >/= 35kg/m2 + comorbidities
A BMI value above approximately 25 kg/m2 associates with a progressive increase in mortality rate and risk of chronic conditions.
Metabolic abnormalities associated with Metabolic Syndrome
Insulin resistance
Glucose intolerance leading to type 2 diabetes
Atherogenic dyslipidemia (including increased triglyceride levels, increased concentrations of non-highdensity lipoprotein [HDL] cholesterol and apolipoprotein B, low HDL cholesterol levels, small dense low-density lipoprotein [LDL] and HDL particles)
Elevated blood pressure (BP)
Subtle chronic inflammation
Prothrombotic profile
How to measure waist circumference?
This variable should be assessed while the patient is standing, placing the tape just above the iliac crest
If a given patient has a large waistline for a given BMI, with altered risk factors, the CVD risk factor profile likely reflects excess abdominal visceral fat
Because the waistline and BMI correlate strongly, waist circumference alone largely reflects _____ adiposity
Total adiposity
The ____________________ of body fat is much more important than adipose tissue mass.
Regional distribution
A large accumulation of lower body fat rather links with a reduced risk of developing these outcomes, consistent with previous findings that hip and thigh fat are associated with a favorable CVD risk profile. In contrast, excess abdominal fat, particularly visceral adipose tissue, confers heightened risk
Identify this hypothesis in visceral obesity
In vitro studies of the metabolic properties of visceral adipose tissue mainly the omental fat depot drained by the portal vein—have shown that these omental adipocytes exhibit a hyperlipolytic state poorly inhibited by insulin compared to subcutaneous adipose tissue.
Therefore, the hypertrophied omental adipocytes in visceral adipose tissue deliver FFAs directly through the portal vein, leading to overproduction of triglyceride-rich lipoproteins, reduction of insulin extraction, and increased hepatic glucose production, hallmarks of obesity and type 2 diabetes.
Portal Free Fatty Acid Hypothesis
Identify
Macrophages accumulate especially in visceral adipose tissue, contributing to local inflammation and an expanding list of “adipokines” that could exacerbate the metabolic risk profile of the patient with excess visceral adiposity. Also, activation of the sympathetic nervous system may occur particularly in visceral adipose tissue.
Visceral Adipose Tissue as an Endocrine Organ
Viscerally obese individuals have an increased accumulation of fat in lean tissues such as the liver, heart, skeletal muscle, and kidney, a phenomenon described as “ectopic fat deposition.”
Thus, excess visceral adipose tissue may be a marker or consequence of the relative inability of subcutaneous adipose tissue to act as a protective “metabolic sink” and thus favor ectopic fat deposition
Visceral Adipose Tissue: Marker of Dysfunctional Subcutaneous Adipose Tissue
______ population develop diabetes because of excess visceral/ectopic fat at lower BMI values than whites or blacks.
Asians
Ectopic fat deposits with systemic effects
Visceral adipose tissue
Intracellular lipids
Liver fat
Pancreas fat
Ectopic fat depots with local effects
Perivascular fat
Epi/pericardial fat
Renal fat
Identify drugs that may lead to weight gain
______________ should not be the sole target for CVD risk reduction in the management of overweight and obese patients.
Weight loss
The most obvious group of patients with disturbed sleeping habits are those with _________________, a condition frequently observed among sedentary overweight and obese patients, particularly those with an excess of visceral/ectopic fat
Sleep apnea
Drugs currently specifically approved for the chronic management of obesity have not yet demonstrated improved cardiovascular outcomes or efficacy in reducing visceral adipose tissue or ectopic fat
Examples?
Subsets of patients that bariatric surgery should be proposed
BMI ≥40 kg/ m2 or BMI ≥35 kg/m2 with obesity-related comorbidities that are difficult to control with lifestyle and pharmacotherapy
Data from a network of multiple randomized controlled trials showed no significant difference in weight loss (BMI reduction and percent of excess weight loss) between Roux-en-Y gastric bypass and sleeve gastrectomy, although they were both superior to laparoscopic adjustable gastric band. Moreover, Roux-en-Y gastric bypass and sleeve gastrectomy resulted in a comparable rate of type 2 diabetes remission in studies with 2 to 5-year follow-up.
