The prevalence of metabolic syndrome depends on the criteria used to determine inclusion and the composition (age, sex, race, ethnicity) of the population studied. The most widely used criteria are those of the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) and the International Diabetes Federation (IDF).[4]Cornier MA, Dabelea D, Hernandez TL, et al. The metabolic syndrome. Endocr Rev. 2008 Dec;29(7):777-822.
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In a large study of the US population using the NCEP-ATP III criteria in 2002, the unadjusted and age-adjusted prevalences of metabolic syndrome were 21.8% and 23.7%, respectively.[5]Ford ES, Giles WH, Dietz WH. Prevalence of the metabolic syndrome among US adults: findings from the third National Health and Nutrition Examination Survey. JAMA. 2002 Jan 16;287(3):356-9.
https://jama.jamanetwork.com/article.aspx?articleid=194559
http://www.ncbi.nlm.nih.gov/pubmed/11790215?tool=bestpractice.com
Similar results were found in a Greek study based on the NCEP-ATP III criteria, in which the age-standardized prevalence of metabolic syndrome was 23.6%.[6]Athyros VG, Bouloukos VI, Pehlivanidis AN, et al; MetS-Greece Collaborative Group. The prevalence of the metabolic syndrome in Greece: the MetS-Greece Multicentre Study. Diabetes Obes Metab. 2005 Jul;7(4):397-405.
http://www.ncbi.nlm.nih.gov/pubmed/15955126?tool=bestpractice.com
Prevalence seems to be higher using the IDF criteria than using the NCEP-ATP III criteria.[4]Cornier MA, Dabelea D, Hernandez TL, et al. The metabolic syndrome. Endocr Rev. 2008 Dec;29(7):777-822.
http://www.ncbi.nlm.nih.gov/pubmed/18971485?tool=bestpractice.com
In a comparison of IDF with NCEP-ATP III criteria, the age-adjusted prevalence of metabolic syndrome defined by NCEP-ATP III was 24.5%, whereas that defined by IDF was 43.4% (P <0.0001), although the calculated vascular event risk was lower in those with IDF-defined metabolic syndrome.[7]Athyros VG, Ganotakis ES, Elisaf M, et al. The prevalence of the metabolic syndrome using the National Cholesterol Educational Program and International Diabetes Federation definitions. Curr Med Res Opin. 2005 Aug;21(8):1157-9.
http://www.ncbi.nlm.nih.gov/pubmed/16083523?tool=bestpractice.com
One study using American Heart Association/National Heart, Lung, and Blood Institute criteria found that from 1999-2000 to 2017-2018, the prevalence of metabolic syndrome in the US increased from 36.2% to 47.3%.[8]O'Hearn M, Lauren BN, Wong JB, et al. Trends and disparities in cardiometabolic health among U.S. adults, 1999-2018. J Am Coll Cardiol. 2022 Jul 12;80(2):138-51.
http://www.ncbi.nlm.nih.gov/pubmed/35798448?tool=bestpractice.com
The study also found that in 2017-2018 the prevalence was higher in older adults, those with lower education, and those with lower income.[8]O'Hearn M, Lauren BN, Wong JB, et al. Trends and disparities in cardiometabolic health among U.S. adults, 1999-2018. J Am Coll Cardiol. 2022 Jul 12;80(2):138-51.
http://www.ncbi.nlm.nih.gov/pubmed/35798448?tool=bestpractice.com
The prevalence of metabolic syndrome increases consistently with increasing age (independently of sex), from 6.7% for patients ages 20 to 29 years, to 43.5% for ages 60 to 69 years, and 42% for ages 70 years and older.[5]Ford ES, Giles WH, Dietz WH. Prevalence of the metabolic syndrome among US adults: findings from the third National Health and Nutrition Examination Survey. JAMA. 2002 Jan 16;287(3):356-9.
https://jama.jamanetwork.com/article.aspx?articleid=194559
http://www.ncbi.nlm.nih.gov/pubmed/11790215?tool=bestpractice.com
[6]Athyros VG, Bouloukos VI, Pehlivanidis AN, et al; MetS-Greece Collaborative Group. The prevalence of the metabolic syndrome in Greece: the MetS-Greece Multicentre Study. Diabetes Obes Metab. 2005 Jul;7(4):397-405.
http://www.ncbi.nlm.nih.gov/pubmed/15955126?tool=bestpractice.com
The prevalence of metabolic syndrome seems to be similar for men and women, but lower in white, non-Hispanic women than men, and higher in African-American women than men.[4]Cornier MA, Dabelea D, Hernandez TL, et al. The metabolic syndrome. Endocr Rev. 2008 Dec;29(7):777-822.
http://www.ncbi.nlm.nih.gov/pubmed/18971485?tool=bestpractice.com
[5]Ford ES, Giles WH, Dietz WH. Prevalence of the metabolic syndrome among US adults: findings from the third National Health and Nutrition Examination Survey. JAMA. 2002 Jan 16;287(3):356-9.
https://jama.jamanetwork.com/article.aspx?articleid=194559
http://www.ncbi.nlm.nih.gov/pubmed/11790215?tool=bestpractice.com
[6]Athyros VG, Bouloukos VI, Pehlivanidis AN, et al; MetS-Greece Collaborative Group. The prevalence of the metabolic syndrome in Greece: the MetS-Greece Multicentre Study. Diabetes Obes Metab. 2005 Jul;7(4):397-405.
http://www.ncbi.nlm.nih.gov/pubmed/15955126?tool=bestpractice.com
The incidence of metabolic syndrome components defined by the same criteria varies by ethnicity. In particular, obesity-related conditions (type 2 diabetes mellitus, hypertension, dyslipidemia) occur more frequently at a lower body mass index in Asians than in white people, and people of Far East Asian origin have a higher risk of cardiovascular disease.[9]Misra A, Khurana L. Obesity and the metabolic syndrome in developing countries. J Clin Endocrinol Metab. 2008 Nov;93(11 Suppl 1):S9-30.
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[10]Wu CC, Yeh WT, Crow RS, et al. Comparison of electrocardiographic findings and associated risk factors between Taiwan Chinese and US White adults. Int J Cardiol. 2008 Aug 18;128(2):224-31.
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In Canada the age-standardized proportional rates of death from coronary artery disease were much higher among Canadians of South Asian origin than among Canadians of European origin, but the reason for this higher prevalence is unknown.[11]Sheth T, Nair C, Nargundkar M, et al. Cardiovascular and cancer mortality among Canadians of European, south Asian and Chinese origin from 1979 to 1993: an analysis of 1.2 million deaths. CMAJ. 1999 Jul 27;161(2):132-8.
https://www.cmaj.ca/content/161/2/132.full
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Metabolic syndrome is more frequent with: current smoking; heavy (>60% of total calories) compared with moderate carbohydrate intake; physical inactivity; alcohol intake; lower household income; and residence in an urban area.[4]Cornier MA, Dabelea D, Hernandez TL, et al. The metabolic syndrome. Endocr Rev. 2008 Dec;29(7):777-822.
http://www.ncbi.nlm.nih.gov/pubmed/18971485?tool=bestpractice.com
Commonly associated comorbid conditions (which are also related to obesity and insulin resistance but are not components of metabolic syndrome required for diagnosis) include polycystic ovary syndrome, hypogonadism, obstructive sleep apnea, and metabolic dysfunction-associated steatotic liver disease (previously known as nonalcoholic fatty liver disease).[4]Cornier MA, Dabelea D, Hernandez TL, et al. The metabolic syndrome. Endocr Rev. 2008 Dec;29(7):777-822.
http://www.ncbi.nlm.nih.gov/pubmed/18971485?tool=bestpractice.com