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Metabolic syndrome is a clustering of clinical findings made up of abdominal obesity, high glucose, high triglyceride, and low high-density lipoprotein cholesterol levels, and hypertension.
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Several definitions of metabolic syndrome have been proposed, with varied requirements, including those by the International Diabetes Federation and the National Cholesterol Education Program Adult Treatment Panel III.
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There is a proposed harmonized international definition that incorporates the criteria for
Metabolic Syndrome
Section snippets
Key points
Definitions
Despite multiple labels in the past, the term MetS is now used universally. It was first formalized by use in a working definition proposed by a diabetes consultation panel for WHO in 1998 and finalized in 1999.10 The section on MetS is a small portion of a document primarily focused on the diagnosis and classification of type 2 diabetes mellitus (T2DM),10 but it provoked discussion and position statements such as from the European Group for the Study of Insulin Resistance (EGIR)11 and the
Epidemiology
The reported prevalence of MetS varies depending on the definition used, age, sex, socioeconomic status, and the ethnic background of study cohorts. However, from studies published in the last decade, an estimated one-quarter to one-third of adults meet MetS criteria in multiple ethnic backgrounds. Cross-sectional data from 1999 to 2010 from the National Health and Nutrition Examination Survey (NHANES) in the United States show that, in adults older than 20 years, the age-adjusted overall
Consequences of MetS
MetS, by definition, is not a disease, but is a clustering of individual risk factors for disease, drawing the attention of the clinician to the probable coexistence of multiple cardiometabolic risk factors in patients when one of the components is found.47 Therefore, a diagnosis of MetS could be expected to predict risk. The goal is to target the different components of MetS with lifestyle and pharmacologic therapies to prevent disease, particularly CVD and diabetes.
Among the differing MetS
Pathophysiology
With extra caloric intake and a sedentary lifestyle, the excess energy balance is stored as fat. Adipose tissue depots are not metabolically equal. Visceral fat, compared with subcutaneous fat,73, 74, 75 has distinct gene expression patterns and is associated with higher insulin resistance, smaller LDL-C and HDL-C particle size, and increased LDL-C and very low–density lipoprotein (VLDL) particle numbers.76 In susceptible individuals, the inability for the β cell to compensate for insulin
Treatment
The treatment of patients with MetS aims to decrease the risk for CVD and T2DM. Overall management involves (1) implementation of lifestyle and dietary changes for weight loss, (2) treatment of atherogenic dyslipidemia, and (3) treatment of hypertension. Many patients with MetS are overweight or obese, and weight reduction through lifestyle changes with caloric restriction and increased physical activity is an important part of the strategy.108 In a systematic review of 11 randomized controlled
Controversies
Multiple critiques have been leveled at the construct of the MetS over the last decade. A Joint Statement of the ADA and the European Association for the Study of Diabetes outlined several thoughtful and now famous concerns regarding MetS.127 Because it is a vehicle first proposed to identify individuals at high risk for CVD, one criticism is that obvious risk factors are not accounted for in the definitions, including age, sex, smoking history, and LDL-C. These additional risk factors may
Summary and future considerations
The definition of MetS has been harmonized to the NCEP definition and there are likely to be additional iterations and discussions of the syndrome in the future. The relationship of WC to cardiovascular risk in varied populations needs further research and refinement.17 The basic research focus will be on further elucidation of pathophysiology and the gene interactions that underpin the clustering of MetS components.
There is no doubt that the clinical use of MetS has had its controversies.
References (130)
The degree of masculine differentiation of obesities: a factor determining predisposition to diabetes, atherosclerosis, gout, and uric calculous disease
Am J Clin Nutr
(1956)Sex hormones, risk factors and cardiovascular disease
Am J Med
(1978)- et al.
Prevalence and trends of metabolic syndrome in the adult US population, 1999–2010
J Am Coll Cardiol
(2013) - et al.
Increased prevalence of metabolic syndrome among hypertensive population: ten years' trend of the Korean National Health and Nutrition Examination Survey
Int J Cardiol
(2013) - et al.
Prevalence of the metabolic syndrome and overweight among adults in China
Lancet
(2005) - et al.
Can metabolic syndrome usefully predict cardiovascular disease and diabetes? Outcome data from two prospective studies
Lancet
(2008) - et al.
Incidence and treatment of metabolic syndrome in newly referred women with confirmed polycystic ovarian syndrome
Metabolism
(2003) - et al.
Differences in traditional and emerging cardiovascular risk factors of subjects discordantly classified by metabolic syndrome definitions of the International Diabetes Federation and the National Cholesterol Education Program
Nutr Metab Cardiovasc Dis
(2009) - et al.
Insulin resistance, the metabolic syndrome, and risk of incident cardiovascular disease: a population-based study
J Am Coll Cardiol
(2007) - et al.
Nonalcoholic fatty liver disease
Best Pract Res Clin Gastroenterol
(2010)
Abdominal obesity: role in the pathophysiology of metabolic disease and cardiovascular risk
Am J Med
Hypertriglyceridemia secondary to obesity and diabetes
Biochim Biophys Acta
Metabolic syndrome, diabetes and atherosclerosis: influence of gene-environment interaction
Mutat Res
Adipocyte death defines macrophage localization and function in adipose tissue of obese mice and humans
J Lipid Res
Dietary saturated fat, gender and genetic variation at the TCF7L2 locus predict the development of metabolic syndrome
J Nutr Biochem
Eskil Kylin (1885–1974)
Obes Rev
Metabolic syndrome: its history, mechanisms, and limitations
Acta Diabetol
Epidemiology and associated risk factors of hyperlipoproteinemia
Z Gesamte Inn Med
Diagnosis of primary hyperlipoproteinemias
Z Gesamte Inn Med
Banting lecture 1988. Role of insulin resistance in human disease
Diabetes
Obesity and diabetes in the developing world–a growing challenge
N Engl J Med
Definition, diagnosis and classification of diabetes mellitus and its complications. Part 1: diagnosis and classification of diabetes mellitus provisional report of a WHO consultation
Diabet Med
Comment on the provisional report from the WHO consultation. European Group for the Study of Insulin Resistance (EGIR)
Diabet Med
American College of Endocrinology position statement on the insulin resistance syndrome
Endocr Pract
Executive summary of the third report of The National Cholesterol Education Program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (adult treatment panel III)
JAMA
Definition of metabolic syndrome: report of the National Heart, Lung, and Blood Institute/American Heart Association conference on scientific issues related to definition
Arterioscler Thromb Vasc Biol
Metabolic syndrome–a new world-wide definition. A Consensus Statement from the International Diabetes Federation
Diabet Med
Harmonizing the metabolic syndrome: a joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention; National Heart, Lung, and Blood Institute; American Heart Association; World Heart Federation; International Atherosclerosis Society; and International Association for the Study of Obesity
Circulation
Metabolic syndrome in youth: chimera or useful concept?
Curr Diab Rep
Prevalence of a metabolic syndrome phenotype in adolescents: findings from the third National Health and Nutrition Examination Survey, 1988–1994
Arch Pediatr Adolesc Med
The metabolic syndrome in children and adolescents–an IDF consensus report
Pediatr Diabetes
Does the constellation of risk factors with and without abdominal adiposity associate with different cardiovascular mortality risk?
Int J Obes (Lond)
Metabolic syndrome in South Asians
Indian J Endocrinol Metab
Gender differences in prevalence of the metabolic syndrome in Gulf Cooperation Council Countries: a systematic review
Diabet Med
The utility of visceral fat level by bioelectrical impedance analysis in the screening of metabolic syndrome–the results of the Kyushu and Okinawa Population Study (KOPS)
J Atheroscler Thromb
Metabolic syndrome as a precursor of cardiovascular disease and type 2 diabetes mellitus
Circulation
The metabolic syndrome in older individuals: prevalence and prediction of cardiovascular events: the Cardiovascular Health Study
Diabetes Care
Increasing prevalence of metabolic syndrome in a Chinese elderly population: 2001–2010
PLoS One
Metabolic syndrome rates in United States adolescents, from the National Health and Nutrition Examination Survey, 1999–2002
J Pediatr
Metabolic syndrome is strictly associated with parental obesity beginning from childhood
Clin Endocrinol (Oxf)
Cardiometabolic aspects of the polycystic ovary syndrome
Endocr Rev
Prevalence and characteristics of the metabolic syndrome in women with polycystic ovary syndrome
J Clin Endocrinol Metab
Impaired glucose tolerance, type 2 diabetes and metabolic syndrome in polycystic ovary syndrome: a systematic review and meta-analysis
Hum Reprod Update
Metabolic syndrome in polycystic ovary syndrome (PCOS): lower prevalence in southern Italy than in the USA and the influence of criteria for the diagnosis of PCOS
Eur J Endocrinol
Revised 2003 consensus on diagnostic criteria and long-term health risks related to polycystic ovary syndrome (PCOS)
Hum Reprod
Dysregulation of glucose metabolism in HIV patients: epidemiology, mechanisms, and management
Endocrine
Metabolic syndrome before and after initiation of antiretroviral therapy in treatment-naive HIV-infected individuals
J Acquir Immune Defic Syndr
Prevalence of metabolic syndrome in HIV-infected patients receiving highly active antiretroviral therapy using International Diabetes Foundation and Adult Treatment Panel III criteria: associations with insulin resistance, disturbed body fat compartmentalization, elevated C-reactive protein, and [corrected] hypoadiponectinemia
Diabetes Care
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