Metabolic syndrome also called insu...

Metabolic syndrome also called insulin resistance syndrome or syndrome X is a cluster of risk factors that is responsible for abundant of the excess cardiovascular disease morbidity among overweight and obese patients and those somebodys with type 2 diabetes mellitus. (1) Differences in body-fat distribution (i.e., gynecoid versus android) associated with an altered metabolic profile were documented in the medical literature 50 years ago. Given the name syndrome X in 1988 (2) each component part of the syndrome has been associated with an increased risk of cardiovascular disease. (3) A report (4) from the National Cholesterol Education Program--Adult Treatment Panel (NCEP--ATP III) identified metabolic syndrome as an independent risk factor for cardiovascular disease and considered it an indication for intensive lifestyle modification.

Definition

The major characteristics of metabolic syndrome include insulin resistance, abdominal obesity, elevated descendants pressure, and lipid abnormalities (i.e., elevated horizontals of triglycerides and low of the same heights of high-density lipoprotein [HDL] cholesterol) Initially defined according to an expert panel of the World Health Organization in 1998 (5) the NCEP--ATP III (4) has created an operational definition of metabolic syndrome: the co-occurrence of any three of the abnormalities mentioned above (Table 1 (45))

Metabolic syndrome is associated with a proinflammatory/prothrombotic state that may include elevated on a levels of C-reactive protein, endothelial dysfunction, hyperfibrinogenemia, increased platelet aggregation, increased flats of plasminogen activator inhibitor 1 elevated uric acid of the same heights microalbuminuria, and a shift toward small, compact particles of low-density lipoprotein (LDL) cholesterol Insulin resistance also has been implicated in polycystic ovary syndrome and nonalcoholic steatohepatitis (NASH).

Epidemiology/Prevalence

The prevalence of metabolic syndrome varies on definition used and population studied. (6) Based onward data from the Third National Health and Nutrition Examination contemplate (1988 to 1994), the prevalence of metabolic syndrome (using the NCEP--ATP III criteria) varies from 16 percent of black men to 37 percent of Hispanic women (Figure 1) (7) The prevalence of metabolic syndrome increases with age and increasing dead body weight. Because the U.S. population is aging, and because more than united half of adults are overweight or obese, it has been estimated that metabolic syndrome before long will overtake cigarette smoking as the primary risk factor for cardiovascular disease. (8) Metabolic syndrome is an level stronger predictor of risk for protoplast 2 diabetes mellitus. (9)

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Etiology

The etiology of the metabolic syndrome has not been established definitively. single hypothesis presumes that the primary cause is insulin resistance. Insulin resistance correlates with visceral fat measured at waist circumference or waist to hip ratio. The link between insulin resistance and cardiovascular disease probably is mediated by dint of oxidative stress, which produces endothelial confined apartment dysfunction, promoting vascular damage and atheroma formation. (10)

The other hypothesis blames hormonal changes for the evolution of abdominal obesity. One research (11) demonstrated that persons with elevated evens of serum cortisol (caused by means of chronic stress) developed abdominal obesity, insulin resistance, and lipid abnormalities. The investigators conclud that this inappropriate activation of the hypothalamic-pituitary-adrenal axis by means of stress is responsible for the link between psychosocial and economic riddles and acute myocardial infarction.

Clinical Evaluation

The routine medical and family history helps to identify patients at risk for cardiovascular disease or diabetes mellitus. Questions about newly come or past weight changes, and a brief diet and physical activity history, (12) including occupational and leisure-time physical activity, are important. The patient should be asked to estimate by what mode many hours a day he or she is sedentary. Questions about typical fare intake and efforts to bring into dietary fat or other specific dietary changes allow the physician to estimate the patient's readiness to change lifestyle habits.

The patient's height, weight, and kin pressure should be measured. corpse mass index (BMI) should be determined at calculating weight (kg)/height ([m.sup.2]), and waist circumference should be measured at the narrowest point between the umbilicus and the rib cage. Waist circumference appears to be a better predictor of cardiovascular risk than waist-to-hip ratio. (13) Patients suspected of having metabolic syndrome should have a fasting grape-sugar level and a fasting lipid profile flat obtained. A euglycemic clamp or homeostasis example assessment is used in research studies to accurately assess insulin resistance, nevertheless is impractical for use in the clinical setting. (14)

Fasting insulin flushs and glucose challenge tests are indicators of insulin resistance still do not need to be measured in principally situations because a fasting grape-sugar level alone suffices for the definition of metabolic syndrome If LDL cholesterol is normal, measuring horizontals of apolipoprotein B is not necessary. recently made known tests that measure LDL particle size are expensive and unnecessary, because grave HDL cholesterol levels and high triglyceride evens predict small, dense LDL particles.