Metabolic Syndrome

Indications for Testing

• High blood pressure
• Overweight or obesity
• Physical inactivity
• Increased waist circumference
• Abnormal results for one component of syndrome (triglycerides, HDL, plasma glucose)
• Suspicion for metabolic syndrome due to other history (use of oral steroids, atypical antipsychotics, myocardial infarction, or stroke)

Criteria for Diagnosis

• Several definitions for metabolic syndrome – 4 main areas of dysfunction
  • Increased visceral adipose
  • Dyslipidemia
  • High blood pressure
  • Derangements in glucose handling
• National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria for diagnosis of metabolic syndrome (Grundy, 2005) – must meet ≥3 of the 5 criteria
  • Waist circumference
    • Men ≥40 inches, women ≥35 inches
    • Measure at the top of the iliac crest after inspiration
  • Triglyceride concentration – ≥150 mg/dL
  • High-density lipoprotein cholesterol (HDL-C) – men <40 mg/dL, women <50 mg/dL, or individual receiving pharmacologic therapy to treat cholesterol
  • Hypertension – blood pressure (BP) ≥130/85 or individual receiving pharmacologic therapy for hypertension
  • Fasting blood glucose – ≥100 mg/dL (American Diabetes Association [ADA] guidelines, 2014)
• Criteria for major definitions of metabolic syndrome

  Criteria for Major Definitions of Metabolic Syndrome
  	WHO 1999 ≥2 of the following	NECP ATP III 2001 ≥3 of the following	AACE 2003 ≥2 of the following	IDF 2005 ≥2 of the following
  Central obesity	BMI >30 or waist-to-hip ratio of >0.9 for men or >0.85 for women	WC >40 in (102 cm) for men or >35 in (88 cm) for women	Obesity is considered a risk factor for insulin resistance and is not included in diagnosis	Europid (Caucasians) – WC >37 in (94 cm) for men; WC >31 in (80 cm) for women Africans – Europid cutoffs should be used in the absence of more specific data Indian Asians – WC >35 in (90 cm) for men; WC >31 in (80 cm) for women
  Dyslipidemia – triglycerides	>150 mg/dL	>150 mg/dL	>150 mg/dL	>150 mg/dL or patient taking specific treatment for hypertriglyceridemia
  Dyslipidemia – HDL-C	<35 mg/dL for men or <40 mg/dL for women	<40 mg/dL for men or <50 mg/dL for women	<40 mg/dL for men or <50 mg/dL for women	<40 mg/dL for men or <50 mg/dL for women
  Hypertension	>140/90 mmHg or documented use of antihypertensive therapy	>130/85 mmHg or documented use of antihypertensive therapy	>130/85 mmHg	>130/85 mmHg or documented use of antihypertensive therapy
  Hyperglycemia	Either impaired glucose tolerance, impaired fasting glucose, insulin resistance, or diabetes	Fasting plasma glucose >100 mg/dL	Fasting plasma glucose 100-125 mg/dL or 2-hour postglucose challenge (75g) 140-200 mg/dL	Fasting plasma glucose >100 mg/dL or previously diagnosed type 2 diabetes
  Microalbuminuria	Urinary albumin-to-creatinine ratio >30 mg/g or albumin excretion >20 μg/min	Not included	Not included	Not included
  Abbreviations: AACE = American Association of Clinical Endocrinologists; BMI = body mass index; BP = blood pressure; EGIR = European Group for the Study of Insulin Resistance; HDL-C = high-density lipoprotein cholesterol; IDF = International Diabetes Federation; IRS = insulin resistance syndrome; MS = metabolic syndrome; NCEP ATP III = National Cholesterol Education Program Adult Treatment Panel III; OGT = oral glucose tolerance; TG = triglycerides; WC = waist circumference; WHO = World Health Organization

Laboratory Testing

• Lipid panel
• Glucose measurement
  • Fasting glucose
  • Glucose tolerance – may also use if criteria not met but suspicion for diabetes mellitus is moderate to high
  • Hemoglobin A1c (HbA1c) – not currently incorporated into diagnostic criteria