Definition
A.Also called insulin resistance syndrome.
B.A group of traits linked to obesity that puts people at risk for both cardiovascular disease (CVD) and type 2 diabetes.
C.Must have three of the following.
1.Waist circumference greater than 40 inches in men; greater than 35 inches in women (varies somewhat by ethnicity depending on which guidelines are used).
2.Triglyceride level of 150 mg/dL or higher or taking medication for elevated triglyceride levels.
3.High-density lipoprotein (HDL) below 40 mg/dL for men and below 50 mg/dL for women or taking medication for low HDL.
4.Blood pressure above 130/85 mmHg or taking antihypertensives.
5.Fasting glucose greater than 100 mg/dL or taking medication for elevated blood glucose.
D.Linked to type 2 diabetes, obesity, CVD, polycystic ovarian syndrome, nonalcoholic fatty liver disease, and chronic kidney disease.
E.Patients with metabolic syndrome are at twice the risk of developing CVD over the next 5 to 10 years as individuals without the syndrome. The risk of developing diabetes is five times higher for individuals with metabolic syndrome.
Incidence
A.About 34% of American adults are thought to have metabolic syndrome.
B.Risk increases as people age.
C.Prevalence is higher in non-Hispanic white men than Mexican American and non-Hispanic black men.
D.The condition is more common in Mexican American women than non-Hispanic black or non-Hispanic white women.
E.Prevalence is increasing globally due to increased obesity and sedentary lifestyles.
Pathogenesis
A.Contributing factors include increased free fatty acid levels, inflammatory cytokines from fat, and oxidative factors.
B.Patients with the characteristics of metabolic syndrome demonstrate a prothrombotic state and a proinflammatory state.
C.Elevated triglycerides and low HDL cholesterol is an atherogenic dyslipidemia condition.
D.The mechanism of how this constellation of risk factors contributes to development of type 2 diabetes and CVD is not completely understood.
Predisposing Factors
A.Sedentary lifestyle.
B.Western diet high in carbohydrates and fats, including saturated fats.
C.Obesity.
D.Family history of diabetes, heart disease, and hyperlipidemia.
Subjective Data
A.Typically, asymptomatic.
B.Patient presentation for a routine physical or a preoperative examination.
Physical Examination
A.Look for abdominal obesity: Record height, weight, body mass index (BMI), waist circumference, and waist to hip ratio.
B.Perform thorough cardiovascular examination.
C.Note skin findings consistent with obesity and insulin resistance.
1.Skin tags.
2.Acanthosis nigricans (see Figure 8.1).
D.Note presence of xanthelasma on medial aspect of eyelids, which is suggestive of hyperlipidemia.
Diagnostic Tests
A.Fasting lipid panel.
B.Fasting glucose.
Differential Diagnosis
A.Type 2 diabetes.
B.Prediabetes.
C.Hyperlipidemia.
D.Hypertension.
E.Obesity.
Evaluation and Management Plan
A.General plan. Treatment centers on two principles.
1.Identify individuals with metabolic syndrome.
2.Use risk factor modification to prevent CVD and type 2 diabetes.
B.Weight loss.
1.Routinely measure weight and anthropometric measurements.
C.Healthy diet.
1.Recommend saturated fat less than 7% of total calories.
2.Reduce trans fats.
3.Limit dietary cholesterol to less than 2,000 mg/d.
4.Restrict total fat to 25% to 35% of total calories.
5.Choose unsaturated fats.
6.Limit simple sugars.
D.Increased physical activity.
1.Encourage 30 to 60 minutes of moderate intensity aerobic activity, preferably daily, supplemented by increase in daily lifestyle activities.
E.Monitoring of blood glucose, lipoproteins, and blood pressure.
F.Treatment of individual risk factors following guidelines for hypertension, hyperlipidemia, and hyperglycemia.
G.Smoking cessation.
Follow-Up
A.Follow-up with primary care providers to monitor underlying problems and to treat cardiovascular risk factors.
Consultation/Referral
A.Endocrinology to manage any underlying problems with diabetes.
B.Cardiology to manage cardiovascular risk factors.
Special/Geriatric Considerations
A.The risk of metabolic syndrome increases with age.
B.People with metabolic syndrome are at increased risk of CVDs.
Bibliography
Aguilar, M., Bhuket, T., & Torres, S. (2015). Prevalence of the metabolic syndrome in the United States, 2003–2012. Journal of the American Medical Association, 313, 1973–1974. doi:10.1001/jama.2015.4260
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American Association of Diabetes Educators. (2008). AADE7 self-care behaviors. Diabetes Educator, 24, 445–449.
American Diabetes Association. (2010, January). Diagnosis and classification of diabetes mellitus. Diabetes Care, 33(Suppl. 1), S62–S69. doi:10.2337/dc10-S062
American Diabetes Association. (2012, January). Standards of medical care in diabetes—2012. Diabetes Care, 35(Suppl. 1), S11–S63. doi:10.2337/dc12-s011
American Diabetes Association Professional Practice Committee. (2013, January). American Diabetes Association clinical practice recommendations: 2013. Diabetes Care, 36(Suppl. 1), S1–S110.