Obesity and the Metabolic Syndrome
Introduction
Obesity is characterized by excess fat mass and defined
according to the body mass index (BMI, kg/m2), a calculation based on weight
and height [BMI = body weight (in kg) ÷ square of stature (height in meters)].
BMI is correlated with body fat and the WHO defines overweight as a BMI of
>25 and obesity as >30 kg/m2.
Clinical Findings
Physiologic changes in the skin related to obesity
include alterations in epidermal barrier function, increased sweating along
with larger skin folds, and increased skin surface pH in intertriginous areas,
poor lymphatic drainage, impaired wound healing and impaired responsiveness of
the microvasculature.
Cutaneous Disorders Associated with Obesity
|
Metabolic ·
Acanthosis
nigricans ·
Acrochordons ·
Keratosis
Pilaris ·
Hyperandrogenism ·
Hirsutism ·
Tophaceous
gout ·
Candidiasis ·
Dermatophytosis ·
Intertrigo ·
Cellulitis ·
Erysipelas ·
Necrotizing
fasciitis Mechanical ·
Plantar
hyperkeratosis ·
Striae
distensae ·
Lymphedema ·
Elephantiasis
nostras verrucosa ·
Venous
stasis ·
Cellulite Miscellaneous ·
Hidradenitis
supprativa ·
Adiposis
dolorosa ·
Psoriasis |
It is now well recognized that the presence of
abdominal—central rather than subcutaneous—obesity (more than just increased
BMI) is associated with insulin resistance, hyperlipidemia, hypertension, and vascular
inflammation. The coexistence of these disorders increases the risk for
diabetes and cardiovascular disease and has been called the metabolic syndrome.
It is not clear that the metabolic syndrome confers risk beyond that of the
individual components but because the traits co-occur, those with one trait are
likely to have others. The most important therapy is weight reduction and
exercise along with adequate control of cardiac risk factors.
Criteria for the clinical
diagnosis of metabolic syndrome
|
1.
Abdominal
Obesity-elevated waist circumference (population and country-specific
definitions) 2.
Serum
triglycerides ≥150 mg/dl (or drug treatment for elevated triglycerides) 3.
Serum
HDL cholesterol <40 mg/dl in men and <50 mg/dl in women (or drug
treatment for low HDL-C) 4.
Blood
pressure ≥130/85 (or drug treatment for elevated blood pressure) 5.
Fasting
plasma glucose≥100 mg/dl (or
drug treatment for elevated blood glucose) |
Metabolic
syndrome is identified by the presence of three of these five criteria. Most
patients with type 2 diabetes mellitus meet criteria for metabolic syndrome.
Women with polycystic ovary syndrome have a
greater frequency of metabolic syndrome and often present with acanthosis nigricans,
acne vulgaris, and hirsutism. An association between psoriasis vulgaris and
metabolic syndrome has also been identified. Patients with moderate to severe
psoriasis are at increased risk of atherosclerotic cardiovascular disease,
which is linked to their propensity for the metabolic syndrome.
The cornerstones of treatment for overweight and obesity
are dietary changes, increased physical activity, and behavioral modification.
In high-risk patients with comorbid conditions, pharmacologic therapy (sibutramine
or orlistat)
can be considered as an additional intervention. In clinically severe obesity,
surgical therapies may be appropriate. All successful patients will require
long-term nutritional adjustments that reduce caloric intake. The role of
liposuction in weight loss has been studied and despite the removal of a large
volume of subcutaneous adipose tissue there is no improvement seen in the
metabolic risk factors associated with obesity.
