Makindo Medical Notes

Any combination of hypercholesterolemia, hypertriglyceridemia, impaired glucose tolerance, diabetes, hyperuricemia, and hypertension.

About

• Syndrome X or Metabolic Syndrome is a group of risk factors for heart disease and stroke.
• It includes diabetes, obesity, hypertension, and cholesterol abnormalities.
• Prevalent in approximately one-third of the US population.

Aetiology

• The underlying factor is insulin resistance, often due to obesity.
• Factors include insulin resistance, visceral adiposity, atherogenic dyslipidemia, endothelial dysfunction, genetic susceptibility, and elevated blood pressure.
• Hypercoagulable states, chronic stress, and abnormal adipocytokines such as TNF, IL-1, IL-6, leptin, and adiponectin are also involved.

Definition

Central obesity (waist circumference > 94 cm for men and 80 cm for Europid women) plus any two of the following four factors:

• Raised triglyceride level (>150 mg/dL or 1.7 mmol/L) or specific treatment for this lipid abnormality.
• Reduced HDL cholesterol (<40 mg/dL in males, <50 mg/dL in females) or treatment for this lipid abnormality.
• Raised blood pressure (≥130/85 mmHg) or treatment for hypertension.
• Raised fasting plasma glucose (≥100 mg/dL or 5.6 mmol/L) or previously diagnosed type 2 diabetes. OGTT is recommended if glucose is ≥100 mg/dL, but not required to define the syndrome.

Risk Factors

• Insulin resistance, aging, sedentary lifestyle.
• Complex, poorly understood physiology.

Clinical Features

• Increased waistline, high blood pressure, diabetes, central obesity.

Differentials

• Cardiovascular disease.
• Increased risk of type 2 diabetes mellitus.
• Prescribed reduction in dietary fat intake.
• Smoking cessation.

Management

• Lifestyle modifications: Initial intervention should focus on diet and exercise. Restricting dietary carbohydrate intake can reduce symptoms of metabolic syndrome.
• Pharmacological treatment: Considered for those whose risk factors are not reduced adequately with lifestyle changes.
• This review outlines the syndrome’s definition, epidemiology, underlying pathogenesis, and treatment approaches for each risk factor.