Prevalence of the metabolic syndrome in US populations

Endocrinol Metab Clin N Am

33 (2004) 333–350

Prevalence of the metabolic syndromein US populations

Earl S. Ford, MD, MPHDivision of Adult and Community Health, National Center for Chronic Disease Prevention

and Health Promotion, Centers for Disease Control and Prevention, 4770 Buford Highway,

MS K66, Atlanta, GA 30341, USA

The metabolic syndrome comprises a constellation of metabolicabnormalities that occur together more often than expected by chance.Elements that typically have been included in the definition includea measure of excess weight, high blood pressure, dyslipidemia, andhyperglycemia. Measures of insulin resistance, inflammation, thrombosis,hyperuricemia, and renal function also have been considered for inclusion.

The triad of hyperglycemia, hypertension, and hyperuricemia wasdescribed as early as 1923 [1]. A major milestone in the history of this syn-drome occurred in 1988, when Reaven proposed the concept of syndrome X,which he described as the co-occurrence of resistance to insulin-stimulated glucose uptake, glucose intolerance, hyperinsulinemia, increasedvery low-density lipoprotein triglyceride, decreased high-density lipoprotein(HDL) cholesterol, and hypertension [2]. This paper stimulated renewedinterest in the syndrome. In 1998, the World Health Organization (WHO)proposed a formal definition of the metabolic syndrome [3]. Three yearslater, the National Cholesterol Education Program Adult Treatment PanelIII (NCEP/ATP III) proposed its definition of the metabolic syndrome[4]. The European Group for the study of Insulin Resistance (EGIR)also developed a definition [5,6]. The attention that the NCEP/ATP IIIreport brought to the metabolic syndrome has ignited an intense interest, asevidencedby thenumerouspublications andmeetings concerning themetabolicsyndrome.

Understanding the prevalence of a condition is critical in helping definethe public health burden of that condition. Meaningful prevalence estimatesare difficult to develop without a suitable definition, however, which, in thecase of the metabolic syndrome, continues to be debated. In this article,

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334 E.S. Ford / Endocrinol Metab Clin N Am 33 (2004) 333–350

I review available data about the prevalence of the metabolic syndrome inthe United States.

Definition of the metabolic syndrome

Researchers have used various terms to describe the cluster ofabnormalities that make up the metabolic syndrome (Box 1). Consequently,the lack of a standard definition has impeded greatly the efforts to determinethe prevalence of this syndrome and further the establishment of asurveillance system. Efforts by WHO, NCEP/ATP III, and EGIR todevelop standard definitions have been critical in trying to determine theprevalence of this syndrome. The three major definitions that have beenproposed are shown in Table 1. Although they share similarities, they alsodiffer considerably. The American Association of Clinical Endocrinologistsalso proposed another definition that includes four criteria [7]. Two majordepartures from the NCEP/ATP III definition were the omission ofa measure of excess weight or central adiposity and the proposed use ofa 2-hour insulin concentration of 140 mg/dL or more as a measure of hyper-glycemia. Because no number of criteria, such as two or three, was proposed,this definition is difficult to operationalize and is not included in thisdiscussion.

To meet the WHO definition, a person must have either glucoseintolerance or insulin resistance plus two of the following four criteria:central obesity, hypertension, dyslipidemia, and albuminuria. In 1999,

Box 1. Terminology used to describe the metabolic syndrome

Athero-thrombogenic syndromeBeer-belly syndromeCardiovascular metabolic syndromeChronic cardiovascular risk factor clustering syndromeDeadly quartetDysmetabolic syndromeDysmetabolic syndrome XInsulin resistance syndromeInsulin resistance-dyslipidemia syndromeMetabolic cardiovascular syndromeMetabolic syndromeMetabolic syndrome XMultiple metabolic syndromePlurimetabolic syndromeReaven’s syndromeSyndrome X

335E.S. Ford / Endocrinol Metab Clin N Am 33 (2004) 333–350

a modification to the WHO definition was proposed: the blood pressurethreshold was lowered from 160/90 mm Hg to 140/90 mm Hg, and thealbumin:creatinine ratio threshold was raised from 20 mg/g to 30 mg/g [8].To meet the NCEP/ATP III definition, a person must have three of thefollowing five abnormalities: abdominal adiposity, hypertension, hyper-triglyceridemia, low high-density lipoprotein (HDL) cholesterol, or hyper-glycemia. Of note is that WHO and NCEP/ATP III included diabetes intheir definitions, but there has been extensive debate about the appropri-ateness of including persons with diabetes in prevalence estimates of themetabolic syndrome. The EGIR definition specifically excludes diabetes.Although all three definitions include a measure of abdominal obesity,elevated blood pressure, dyslipidemia, and hyperglycemia, the exactmeasures and cut points used to define elevations differ among the threedefinitions.

The NCEP/ATP III definition is perhaps the most straightforward toimplement because the five criteria are clearly defined. Perhaps the onlydetails that were not specifically spelled out were whether people who usedantihypertensive medications should be considered as having high bloodpressure and whether people who use hypoglycemic medications should becounted as having hyperglycemia. The WHO definition is more difficult toimplement for several reasons. First, an oral glucose tolerance test should beperformed so that hyperglycemia can be defined using WHO criteria.Second, microalbuminuria is not commonly measured in medical practice.Finally, insulin resistance must be determined. Because a gold standardmethod for measuring insulin resistance currently is not feasible in clinicalpractice, surrogate measures that depend one way or another on measur-ing insulin concentration are used. At least two difficulties exist with thisapproach, however. First, the measurement of insulin concentrationcurrently is not adequately standardized [9]. Second, even if insulinconcentration could be measured accurately, a cut point for insulinresistance has not been established specifically. The WHO proposalsuggested that insulin resistance be defined as follows: ‘‘under hyper-insulinaemic euglycaemic conditions, glucose uptake below lowest quartilefor background population under investigation.’’ Investigators have im-plemented this definition in different ways, however, which has resulted invarying estimates of insulin resistance and the prevalence of the metabolicsyndrome.

Prevalence of the metabolic syndrome

Before the NCEP/ATP III report proposed a definition of the metabolicsyndrome, several studies had estimated the prevalence of the metabolicsyndrome based on other definitions (Table 2). These estimates ranged from4.6% among white women in the Atherosclerosis Risk in Communities

Table 1

Definitions of the metabolic syndrome

Criteria NCEP/ATP I

European Group for the Study of

Insulin Resistance

�Three of th

five criteria

paired

sting

No diabetes plus �two of the

following four criteria:

Central obesity 1. Waist circu

>102 cm i

>88 cm in

men

ody

1. Waist circumference �94 cm

for men, �80 cm for women

Dyslipidemia 2.Trigyceride

(1.695 mm

mol/L)

mol/L)

2. Triglycerides �190 mg/dL

(2 mmol/L) or high-density

lipoprotein cholesterol

concentration\40 mg/dL

(1 mmol/L) or treatment

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II World Health Organization

e following

:

Presence of diabetes mellitus, im

glucose tolerance, impaired fa

glucose, or insulin resistance

plus �two of the following

four criteria:

mference

n men and

women

1. Waist-to-hip ratio of >0.9 in

or >0.85 in women and/or b

mass index >30 kg/m2

s �150 mg/dL

ol/L)

2. Triglycerides �150 mg/dL

(1.695 mmol/L) and/or

high-density

lipoprotein

cholesterol\35 mg/dl (0.9 m

in men and\39 mg/dL (1 m

in women

3. Low high-density

Hig

p

3. Blood pressure

�160/90 mm Hga3. Blood pressure: systolic blood

pressure �140 or diastolic blood

pressure �90 or treatment for

hypertension

Hig

)

Oth 4. Microalbuminuria: urinary

albumin excretion rate

�20 lg/min or albumin/

creatinine ratio �20 mg/ga

4. Insulin resistance or fasting

insulin concentration above

the upper quartile for

nondiabetic subjects

ted blood pressure was defined as �140/90 mm Hg and the albumin:creatinine ratio was increased to

30

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lipoprotein cholesterol:

\40 mg/dL (1.036 mmol/L)

in men and\50 mg/dL

(1.295 mmol/L) in women

h blood

ressure

4. Blood pressure

�130/85 mm Hg

h glucose 5. Fasting glucose:

�110 mg/dL (�6.1 mmol/L

er

a In 1999, revised WHO criteria were published. Eleva

mg/g.

Table 2

Preva

Refer efinition Prevalence

Haffn wo or more or three or

more of the following:

15.8% (2 criteria)

4.8% (3 criteria)

. Hypertension: DBP

�95 mm Hg and/or

medication

. Hyperglycemia: old

WHO criteria or

medications—

NIDDM, IGT

. Low HDLC:

men\35 mg/dL

(0.91 mmol/L),

women\45 mg/dL

(1.17 mmol/L)

. Hypertriglyceridemia:

>250 mg/dL (2.82

mmol/L)

Schm hree or more of the

following:

African-American men:

11.5%

. Hypertension: �140/

90 mm Hg and/or

medications

White men: 10.6%

. Diabetes: �140 mg /

dL (7.8 mmol/L) and/

or diagnosis and/or

medication

African-American

women: 4.6%

. Hyperuricemia: �476

lmol/L

White women: 4.6%

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lence of the metabolic syndrome from US studies

ence Study Period Population D

er et al [10] San Antonio Heart

Study

1979–1982 1125 Mexican-American

and white participants

aged 25–64 years

T

1

2

3

4

idt et al [11] Atherosclerosis Risk in

Communities Study

1987–1989 14,481 African-

American and white

men and women

aged 45–64 years

T

1

2

3

4. Hypertriglyceridemia:

�200 mg/dL (2.26

ol/L)

w HDLC:\35 mg/

(0.9 mmol/L)

L abetes: medication

fasting glucose

140 mg/dL

8 mmol/L)

Total: 2.5%

pertension: SBP

40 mm Hg or DBP

0 mm Hg or

dication


2.8%

slipidemia: TG

200 mg/dL (2.26

ol/L) and/or

LC\35 mg/dL

9 mmol/L) in men,

5 mg/dL (1.2

ol/L) in women

African-American

women: 4.0%

White men: 2.2%

White women: 2.1%

M or more of the

lowing:

Men: 29.4%

perinsulinemia:

ting insulin: >90th

centile of those

h normal glucose

erance

Women: 23.1%

slipidemia: HDLC:

n\35 mg/dL (0.91

ol/L), women\45

/dL (1.16 mmol/L)

TG: >200 mg/dL

26 mmol/L)

(continued on next page)

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mm

5. Lo

dL

iese et al [12] Atherosclerosis Risk in

Communities Study

1987–1989 14,406 African-

American and white

men and women aged

45–65 years

6. Di

or

>

(7.

7. Hy

�1

�9

me

8. Dy

>

mm

HD

(0.

\4

mm

eigs et al [13] Framingham Offspring

Study

1991–1993 1144 men, 1295 women

aged 26–82 years

Two

fol

1. Hy

fas

per

wit

tol

2. Dy

me

mm

mg

or

(2.

Table 2 (continued)

Reference Study Period Population Definition Prevalence

Obesity: central:

WHR >1 in men,

>0.9 in women or

overall: �27.8 kg/m2

in men, �27.3 in

women

W hree or more of the

following:

Men: approximately

17%

HDLC: lowest

sex-specific quintile

Women: approximately

17%

Total cholesterol:

highest sex-specific

quintile

BMI: highest sex-

specific quintile

SBP: highest sex-

specific quintile

TG: highest sex-

specific quintile

Plasma glucose:

highest sex-specific

quintile

Ka hree or more of the

following:

Men: 22%

Hypertension Women: 27%

Dyslipidemia

Glucose intolerance

Obesity

Left ventricular

hypertrophy

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3.

ilson et al [14] Framingham Offspring

Study

1971–1974 2406 Men, 2569 women

aged 18–74 years

T

1.

2.

3.

4.

5.

6.

nnel [15] Framingham Study Not stated Not stated T

1.

2.

3.

4.

5.

Ford et al [16] National Health and

Nutrition Examination

1988–1994 8814 Men and women

aged �20 years

NCEP/ATP III White men: 24.8%


16.4%

Mexican-American men:

28.3%

Other men: 20.9%

White women: 22.8%

African-American

women: 25.7%

Mexican-American

women: 35.6%

Other women: 19.9%

Ara NCEP/ATP III 34.3%

NCEP/ATP III 12.9%

Res NCEP/ATP III 55.2%

Han NCEP/ATP III 31%

WHO 1999 31%

Me NCEP/ATP III White men: 24.7%

White women: 21.3%


29%

Mexican-American

women: 32.8%


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Survey III

neta et al [17] San Diego County 1995–1999 294 Filipino women

aged 50–69 years

Rancho Bernardo

Heart and Chronic

Disease Study

1992–1995 379 White women aged

50–69 years

nick et al [18] Strong Heart Study Baseline

examination

4549 American Indians

aged 45–74 years

son et al [20] Pima 1993–1998 890 Pima Indians aged

�20 years without

diabetes

igs et al [19] San Antonio Heart

Study

1988–1996 470 White men, 611

white women, 682

Mexican-American

men, 974 Mexican-

American women

Age: 30–79 years

without diabetes

Table 2 (continued)

Reference Study Period Population Definition Prevalence

HO 1999 White men: 24.7%

White women: 17.2%


32%

Mexican-American

women: 28.3%

CEP/ATP III White men: 26.9%

White women: 21.4%

HO 1999 White men: 30.3%

White women: 18.1%

H CEP/ATP III Total: 26.9%

Whites NFG/NGT:

14.1%

Whites IFG/IGT:

42.8%

African-Americans

NFG/NGT: 6.8%

Whites IFG/IGT:

42.6%

Hispanics NFG/NGT:

22.8%

Hispanics IFG/IGT:

50%

HO 1999 Total: 34.1%

Whites NFG/NGT:

11.7%

Whites IFG/IGT:

57.2%

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W

Framingham Offspring

Study

1991–1995 1503 White men,

1721 white women

aged 30–79 years

N

W

anley et al [21] Insulin Resistance

Atherosclerosis Study

1992–1994 1035 Nondiabetic

participants; mean

age 53.8–56.3 years

N

W

African Americans

NFG/NGT: 13%

Whites IFG/IGT:

56.5%

Hispanics NFG/NGT:

26.5%

Hispanics IFG/IGT:

67.7%

Chil

ad

Che Presence of following

four criteria:

White children: 4.8%

1. High blood pressure:

extreme quartiles

specific for race, sex,

and age

African-American

children: 3.7%

2. Dyslipidemia: high

TG and/or low

HDLC: extreme

quartiles specific for

race, sex, and age

White adolescents: 3.0%

3. Hyperinsulinemia:

extreme quartiles


and age

African-American

adolescents: 2.7%

4. Obesity without

hyperglycemia:

extreme quartiles


and age


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dren and

olescents

n et al [24] Bogalusa Heart Study 1991–1993 1088 Children aged

5–11 years; 1427

adolescents aged

12–17 years

Table 2 (continued)

Ref pulation Definition Prevalence

Coo 0 Boys and girls aged

2–19 years

Three or more of the

following:

Male: 6.1%

1. Abdominal obesity:

waist circumference

�90th percentile

Female: 2.1%

2. Hypertriglyceridemia:

�110 mg/dL

(1.243 mmol/L)

3. Low high-density

lipoprotein

cholesterol:

\40 mg/dL

(1.036 mmol/L)

4. High blood pressure:

�90th percentile

5. High fasting glucose:

�110 mg/dL

(�6.1 mmol/L)

C; high-density lipoprotein cholesterol; IFG; impaired fasting glucose; IGT;

imp se tolerance; NIDDM; non–insulin-dependent diabetes mellitus; SBP; systolic

bloo

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erence Study Period Po

k et al [25] National Health and

Nutrition Examination

Survey III

1988–1994 243

1

Abbreviations: BMI; body mass index; DBP; diastolic blood pressure; HDL

aired glucose tolerance; NFG; normal fasting glucose; NGT: normal gluco

d pressure; TG; triglycerides.


Study to 29.4% among men in the Framingham Offspring Study.Comparing prevalence estimates from these studies is difficult for severalreasons. First, all of the studies used different definitions of the metabolicsyndrome. An example of how different definitions can result in widelydifferent prevalence estimates is demonstrated by two publications of theAtherosclerosis Risk in Communities Study [11,12]. Second, the de-mographic composition of the studies differed. Finally, the studies wereconducted in different geographic regions and during different time periods.

Although the definition of the metabolic syndrome developed by NCEP/ATP III is open to discussion, a major advantage is that it allows studyinvestigators to determine the prevalence of the metabolic syndrome inexactly the same way, which improves cross-study comparisons ofprevalence estimates. Since the release of this definition, several US studieshave produced prevalence estimates of the metabolic syndrome based on theNCEP/ATP III definition.

Results from National Health and Nutrition Examination Survey III,which was conducted from 1988 to 1994, showed that the unadjustedprevalence of the metabolic syndrome among adults aged 20 years or olderwas 21.8%, and the age-adjusted prevalence was 23.7% [16]. The prevalencewas 6.7% among participants aged 20 to 29 years, peaked at 43.5% amongpersons aged 60 to 69 years, and was 42% among participants aged 70 yearsor older. Significant racial or ethnic differences also were present. Amongmen, the age-adjusted prevalence was 24.8% among whites, 16.4% amongAfrican Americans, 28.3% among Mexican Americans, and 20.9% amongother participants. Among women, the age-adjusted prevalence was 22.8%among whites, 25.7% among African Americans, 35.6% among MexicanAmericans, and 19.9% among other participants. Applying the prevalenceestimates from NHANES III to the US population for the year 2000suggested that approximately 47 million people in the United States had themetabolic syndrome. If people without diabetes (self-reported diabetes ora fasting plasma glucose concentration �126 mg/dL) were excluded, the age-adjusted prevalence was 20.1% (men, 20%; women, 20.1%).

Among Filipino women aged 50 to 69 years who lived in San DiegoCounty, the prevalence of the metabolic syndrome was found to be 34%[17]. In comparison, the prevalence among white women who participated inthe Rancho Bernardo Heart Study and Chronic Disease Study a few yearsearlier was 13%. The prevalence of the metabolic syndrome was high(approximately 55%) among participants of the Strong Heart Study [18].More recently, the prevalence of the metabolic syndrome was estimated forparticipants of the Framingham Offspring Study and the San Antonio HeartStudy who did not have diabetes [19]. The prevalences ranged from 21.3%to 32.8%. Like NHANES III, the prevalence was higher among Mexican-American participants than white participants. Among Pima Indians whodid not have diabetes, 31% were found to have the metabolic syndrome [20].Finally, the prevalence of the metabolic syndrome among participants of the


Insulin Resistance Atherosclerosis Study who had a normal fasting glucoseand normal glucose tolerance was 14.1% among whites, 6.8% amongAfrican Americans, and 22.8% among Hispanics [21]. Among participantswho had impaired fasting glucose or impaired glucose tolerance, 42.8% ofwhites, 42.6% of African Americans, and 50% of Hispanics had themetabolic syndrome.

Little is known about the prevalence of the metabolic syndrome amongchildren and adolescents. Given the rapid increase in obesity and type 2diabetes in this group [22,23], knowing the prevalence of the metabolicsyndrome is important for monitoring the health of children andadolescents. As with adults, however, the lack of a standard definition inthis age group has hampered efforts to calculate the prevalence. Researchersfrom the Bogalusa Heart Study examined clustering of risk factors forcardiovascular disease in young people. They found that the prevalence ofthe metabolic syndrome was 4.8% for white children aged 5 to 11 years, 3%for white adolescents aged 12 to 17 years, 3.7% for African-Americanchildren aged 5 to 11 years, and 2.7% for African-American adolescentsaged 12 to 17 years [24]. Using the components of the metabolic syndromeas proposed by NCEP/ATP III but modifying the thresholds, the prevalenceof the metabolic syndrome among US children and adolescents aged 12 to19 years was estimated to be 6.1% among boys and 2.1% among girls [25].

Comparing the National Cholesterol Education Program Adult Treatment

Panel III and World Health Organization Definitions in

United States studies

A few studies have compared prevalence estimates of the metabolicsyndrome using the definitions of the NCEP/ATP III and WHO. Resultsfrom NHANES III showed that the prevalence of the metabolic syndromewas similar using both definitions [26]. The age-adjusted prevalence of thesyndrome was 23.9% (men, 24.2%; women, 23.5%) using the NCEP/ATPIII definition and 25.1% (men, 27.9%; women, 22.6%) using the WHOdefinition. The two definitions did produce different estimates for variousracial or ethnic groups, however. The estimates for African-American andMexican-American participants were higher under the WHO definition. Themost pronounced difference occurred among African-American men: theprevalence was 16.5% using the NCEP/ATP III definition and 24.9% usingthe WHO definition. Among Pima Indians who did not have diabetes, theprevalence of the metabolic syndrome was 31% under both definitions [20].Comparisons of prevalence estimates of the two definitions also have beenconducted with data from the Framingham Offspring Study and SanAntonio Heart Study [19]. In the Framingham Offspring Study, the WHOdefinition produced somewhat higher estimates than the NCEP/ATP IIIdefinition among men (NCEP/ATP III, 26.9%; WHO, 30.3%) but a lowerestimate among women (NCEP/ATP III, 21.4%; WHO, 18.1%). In the San


Antonio Heart Study, the two definitions produced identical estimates forwhite men, but the WHO definition produced a lower estimate among whiteand Mexican-American women and a higher estimate among Mexican-American men. Finally, the prevalence of the metabolic syndrome using theWHO definition (34.1%) was higher than that using the NCEP/ATP IIIdefinition (26.9%) among participants of the Insulin Resistance Athero-sclerosis Study who did not have diabetes [21]. This study recruited highproportions of participants with impaired glucose tolerance or diabetes. Theracial or ethnic patterns were similar to those described using the NHANESIII data. No estimates in US populations have been made using the EGIRdefinition.

Trends in the metabolic syndrome

To date, information about temporal trends in the prevalence of themetabolic syndrome is not available. Examining the trends in thecomponents that make up the metabolic syndrome may be instructive,however. During the period from 1988 to 1994 through 1999 to 2000,increases have occurred in the prevalence of obesity [27], mean waistcircumference [28], and the prevalence of hypertension [29]. The prevalenceof diabetes remained stable, however [30]. Although little is known abouttrends in concentrations of triglycerides and HDL cholesterol, the trends inthe other components that are part of the definition for the metabolicsyndrome suggest that an increase in the prevalence of the syndrome amongUS adults probably occurred between the period from 1988 to 1994 and1999 to 2000. The prevalence of the metabolic syndrome among childrenand adolescents in the United States probably also increased because ofunfavorable trends in components and determinants of the metabolicsyndrome [31].

Summary

By highlighting the metabolic syndrome in its report, the NCEP/ATP IIIdrew new attention to this syndrome and at the same time served tounderscore the gaps in our related knowledge. One such gap was thedimension of the metabolic syndrome epidemic in the United States. Toestablish the prevalence of the metabolic syndrome in the United States,a standard definition was required. For too long, such a definition wasunavailable, which resulted in a multitude of definitions being used togenerate widely varying prevalence estimates. By providing a workingdefinition of the syndrome, NCEP/ATP III has contributed to betterdefining the burden of the metabolic syndrome in the United States and hashelped to establish the metabolic syndrome as an emerging public health


issue. The NCEP/ATP III’s standard definition allows the development ofa surveillance system for this syndrome in the United States and facilitatescomparisons among studies. Future changes to this and other definitions ofthe metabolic syndrome are likely to occur as more is learned aboutthe underlying mechanisms of this syndrome. Improving the clarity of thecriteria will help to avoid differential implementation of definitions of themetabolic syndrome and improve the ability to make comparisons amongstudies. The appropriateness of cut points of individual components of thesyndrome may require review. For example, the need for ethnic-specific cutpoints to define overweight and obesity has been debated [32,33]. Ascurrently considered, the metabolic syndrome is an all-or-nothing diagnosis.Future refinements of the definition may include developing a classificationscheme comparable to that for excess weight to reflect a gradient of risk formetabolic syndrome–associated morbidity and mortality. A major improve-ment would be for a single standard definition of this syndrome to beadopted by all, thus facilitating cross-study and population comparisons.

The prevalence of the metabolic syndrome using either the NCEP/ATPIII or WHO definitions is high and likely increasing among US adults. Thelarge number of people with the metabolic syndrome has seriousimplications for public health and clinical practice. The associated costs,which have not been defined so far, are likely to be substantial. Futureincreases in the incidence of cardiovascular disease and diabetes couldoccur. Because patients with the metabolic syndrome will make up a largeproportion of the practices of health care professionals, health careprofessionals must be knowledgeable about the metabolic syndrome andbe prepared to diagnose it. The NCEP/ATP III definition providesa straightforward approach to the diagnosis. Measurements of bloodpressure and concentration of triglycerides, HDL cholesterol, and glucoseare routinely performed. Routine measurements of patients’ waist circum-ference will be required for accurate diagnosis of the metabolic syndromeusing the NCEP/ATP III definition, however.

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Prevalence of the metabolic syndrome in US populations