Prevalence of Metabolic Syndrome and Its Associations with Other Metabolic Disorders and Cardiovascular Changes in Health Examination Population in Beijing

Chin Med Sci J December 2009

Vol. 24, No. 4 P. 227-230

CHINESE MEDICAL SCIENCES JOURNAL ORIGINAL ARTICLE

Prevalence of Metabolic Syndrome and Its Associations with Other Metabolic Disorders and Cardiovascular Changes in Health Examination Population in BeijingƸ Wei-ming Kang1, Jie-shi Zhang1, Min-shan Wang2, Ying-chao Gu1, and Jian-chun Yu1* 1

Department of General Surgery, 2Health Examination Center, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China

Key words: metabolic syndrome; prevalence; metabolic disorders; cardiovascular changes Objective To investigate the prevalence of metabolic syndrome (MS) and its associations with other metabolic disorders and cardiovascular changes in health examination population in Beijing. Methods Totally, 10 916 individuals who received health examination in Health Examination Center of Peking Union Medical College Hospital were enrolled. The height, weight, blood pressure, serum levels of triglyceride, high-density lipoprotein cholesterol (HDL-C), and fasting blood glucose were recorded. MS was diagnosed based on the working criteria of Chinese Diabetes Society 2004 (CDS2004). Meanwhile, other metabolic disorders, including fatty liver and hyperuricemia, were recorded. The cardiovascular changes were reflected by the reports of electrocardiogram (ECG) ST-T changes and atherosclerosis of retinal arteries. Results The overall prevalence rate of MS was 6.1% (666/10 916) in the population. The prevalence rate of MS in male was much higher than that in female (9.0% vs. 2.7%, P=0.000). For individuals with MS, the prevalence rates of fatty liver and hyperuricemia were significantly higher than those without MS, respectively (70.4% vs. 35.4%, P=0.000; 29.9% vs. 17.7%, P=0.000). As for cardiovascular changes, the prevalence rates of ECG ST-T changes and atherosclerosis of retinal arteries were significantly higher in individuals with MS than those without MS, respectively (13.8% vs. 11.7%, P=0.012; 12.0% vs. 6.8%, P=0.000). Conclusions The prevalence of MS in Beijing population is high. The individuals with MS have a higher risk for other metabolic disorders and cardiovascular changes. Received for publication August 21, 2009. *Corresponding author Tel: 86-10-65296038, E-mail: yu-jch@vip. sohu. com ƸSupported by the Grant for Young Scientist of PUMC Hospital (200577A).

M

ETABOLIC syndrome (MS) is a clustering of several metabolic factors that increase the risk for atherosclerotic cardiovascular disease and diabetes mellitus. Its prevalence and

predisposition to atherosclerotic cardiovascular disease

228

CHINESE MEDICAL SCIENCES JOURNAL

and diabetes mellitus have been reported in western

December 2009

Diagnostic criteria

1

countries. In China, with the westernization of lifestyle

Based on the recommendation of Chinese Diabetes Society

and aging of population in recent years, the prevalences of

2004 (CDS2004), the working criteria of MS were defined

overweight, obesity, and abnormity of blood lipids have

as meeting three or more of the following five features: (1)

rapidly elevated. Considering the importance and implica-

BMIı25 kg/m2; (2) serum TGı1.70 mmol/L; (3) serum

tions of MS for health care, our study aimed to investigate

HDL-C<0.91 mmol/L for male or serum HDL-C<1.01 mmol/L

the prevalence of MS and its associations with other

for female; (4) systolic blood pressure (SBP) ı140 mm Hg

metabolic disorders and cardiovascular changes in the

and/or diastolic blood pressure (DBP) ı90 mm Hg; (5)

health examination population in Beijing.

fasting blood glucoseı6.1 mmol/L.2 And hyperuricemia was defined as serum level of uric acid higher than 390 mmol/L.

SUBJECTS AND METHODS Subjects and subgroups

Statistical analysis

Totally, 10 916 individuals (5 910 males and 5 006 females)

The software of SPSS 16.0 was used for all analyses. The

who received health examination from April 2006 to De-

count data were expressed as percentage. Chi-square test

cember 2007 in Health Examination Center of Peking Union

was used to compare the differences of prevalence rates

Medical College Hospital were enrolled in our study, with a

between groups. Statistical significance was defined as P

mean age of 47.7±12.2 (range, 18-86) years. The majority

value <0.05.

of our subjects were employees from government, companies, etc. The whole study population was divided into

RESULTS

eight subgroups according to their ages, with a ten-year interval for each subgroup.

Prevalence of MS Among 10 916 individuals, there were 666 cases of MS

Examination methods

according to the criteria of CDS2004; the overall preva-

Fasting weight measured by 0.1 kg without shoes and

lence rate of MS was 6.1%. In male group, the prevalence

height measured by 0.1 cm without shoes were recorded,

rate of MS was 9.0% (531/5 910). While the overall pre-

then body mass index (BMI) was calculated with the fol-

valence rate in female group was 2.7% (135/5 006), which

2

lowing formula: BMI=weight/height . Blood pressure was

was significantly lower than that of male group (P=0.000).

recorded by 1 mm Hg. Fasting venous blood samples were

The prevalence rate of MS increased with age between 18

collected and sent to the central laboratory to test the

and 60 years, in both male and female groups, while there

levels of serum triglyceride (TG), high-density lipoprotein

was a decrease in the 61-70 years subgroup for male. For

cholesterol (HDL-C), blood glucose, and serum uric acid

the subgroups between 21 and 60 years, the prevalence

with the biochem-analyzer (Olympus AU5400). The fundus

rates of MS of male groups were significantly higher than

examination, abdominal ultrasound, and electrocardio-

those of the corresponding female groups (P=0.000).

gram (ECG) were performed to identify the metabolic and

However, in the 71-80 years subgroup, the prevalence rate

cardiovascular changes.

of female group was significantly higher than that of the corresponding male group (P=0.001) (Table 1).

Table 1. Prevalence rates of metabolic syndrome in population classified according to age and gender Subgroups by age (yr)

Total (%) 1.0 (

64)

0.0 (

0/

40)

1.000

3.0 ( 41/ 1 364)

5.5 ( 34/ 617)

0.9 (

7/ 747)

0.000

31-40

5.6 (161/ 2 869)

9.3 (146/1 576)

1.2 ( 15/1 293)

0.000

41-50

6.6 (214/ 3 260)

9.8 (183/1 876)

2.2 ( 31/1 384)

0.000

51-60

7.3 (153/ 2 110)

10.2 (115/1 128)

3.9 ( 38/ 982)

0.000

61-70

7.0 ( 57/

816)

6.7 ( 27/ 401)

7.2 ( 30/ 415)

0.781

9.9 ( 35/

352)

9.7 ( 21/ 216)

10.3 ( 14/ 136)

>80

9.8 (

41)

Total

6.1 (666/10 916)

1.6 (

12.5 (

1/

P value

21-30

4/

104)

Female (%)

18-20

71-80

1/

Male (%)

4/

32)

9.0 (531/5 910)

0.0 (

0/

0.001

9)

0.559

2.7 (135/5 006)

0.000

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CHINESE MEDICAL SCIENCES JOURNAL

229

prevalence rate of MS from 18 to 86 years was 6.1%.

Relations between MS and other metabolic disorders Based on the examination results of abdominal ultrasound,

Hyperuricemia is a common metabolic disorder com-

the prevalence rate of fatty liver was 70.4% (469/666) in

plicating the MS. The high level of uric acid has been proved

MS group, which was significantly higher than that of

to damage the vessel endothelium, which is involved in the

non-MS group (35.4%, 3627/10 250; P=0.000). And simi-

etiology of hypertension.5 And MS is known as the major

lar situation also occurred in those with hyperuricemia. The

primary risk factor for the fatty liver.6 The prevalence rates

prevalence rate of hyperuricemia was 29.9% (199/666) in

of hyperuricemia and fatty liver should be taken into ac-

MS group, which was significantly higher than that of

count in the study. We confirmed that individuals with MS

non-MS group (17.7%, 1815/10 250; P=0.000)(Table 2).

stand more chance to have hyperuricemia and fatty liver, than non-MS ones do. Some other studies proved that MS was related with

Relations between MS and cardiovascular changes As for cardiovascular changes screening, the prevalence

the severity of coronary artery disease and left ventricular

rates of ECG ST-T changes and atherosclerosis of retinal

hypertrophy in in-patient patients.7 In this study, we also

arteries were significantly higher in MS groups (8.0% and

evaluated the status of ECG ST-T changes and athero-

12.0%, respectively) than those in non-MS groups (5.7%

sclerosis of retinal arteries, as the index of cardiovascular

and 6.8%, respectively, P<0.05) (Table 3).

disease, in individuals taking health examination. The results indicated that individuals with MS had poor vessel situation. These findings may suggest that MS is a risk

DISCUSSION

factor for cardiovascular disease.

MS, including the clustering of overweight, hyperten-

In conclusion, the prevalence of MS in Beijing popula-

sion, abnormity of blood lipid and glucose, has been con-

tion is high. The individuals with MS have a higher risk for

sidered as a risk factor for cardio-cerebral-vascular disease

other metabolic disorders and cardiovascular changes.

1

and diabetes. Since there was no universal agreement, some different standards were used to define the MS. Cur-

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4

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Table 2. Relations between metabolic syndrome and fatty liver as well as hyperuricemia Fatty liver

Group Total (cases) Metabolic syndrome (cases) Non-metabolic syndrome (cases)

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Yes

No

Yes

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6 820

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469

197

199

467

3 627

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1 815

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61.586

0.000

0.000

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F

2

P value

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Yes

No

Yes

No

634

10 282

777

10 139

53

613

80

586

581

9 669

697

9 553

6.320

25.695

0.012

0.000

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