Cardiovascular risk factors are really linked in the metabolic syndrome: this phenomenon suggests clustering rather than coincidence.
BACKGROUND
The accumulation of cardiovascular risk factors can be seen in a single person but it needs to be determined if this occurs more frequently than might be explained by mere coincidence.


METHODS
This study involved 119,412 adults: 41,819 males and 77,593 females, who were 40 years of age or older and who underwent an annual health examination. From the clinical and biochemical data, the actual prevalence of a combination of 3 or more factors: abnormal body mass index (> or =25.0), hypertension, high triglyceride (> or =150 mg/dl), low HDL cholesterol (<40 mg/dl) and abnormal fasting glucose metabolism (fasting blood sugar > or =110 mg/dl or HbA1c. > or =5.5%) was determined. Then, the prevalence of a corresponding combination of 3-5 factors was predicted from the prevalence of each factor on the assumption that their combination occurs as a result of coincidence.


RESULTS
The criteria of metabolic syndrome (> or =3 risk factors) was met in 17,842 (14.9%) of the examinees. The actual prevalence of any combination of 3-5 factors of metabolic syndrome was more frequent than those expected to occur by coincidence (P < 0.001). When compared with the prevalence of the total examinees, the prevalence of obesity and insulin resistance was 2.5 and 2.9 times higher in metabolic syndrome compared to that in the total examinees but it was 1.7 to 2.1 times higher in hypertension and high triglyceride. The former two were clustering more than hypertension or high triglyceride in metabolic syndrome. Abnormal levels of serum creatinine and total cholesterol were found more often in metabolic syndrome.


CONCLUSIONS
Combinations of risk factors of metabolic syndrome were found more frequently than coincidental phenomenon in the subjects from the general population. These finding suggest that these risk factors do cluster and obesity and insulin resistance were suggested to be linked with metabolic syndrome more than hypertension or high triglyceride.
Aizawa
Yoshifusa
Y
Niigata University Graduate School of Medical and Dental Science Division of Cardiology, Japan. aizaways@med.niigata-u.ac.jp
Kamimura
Norihito
N
Watanabe
Hiroshi
H
Aizawa
Yoshiyasu
Y
Makiyama
Yashiro
Y
Usuda
Yoshimaru
Y
Watanabe
Tohru
T
Kurashina
Yoshiaki
Y
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology* / Q000503:physiopathology; D008076:Cholesterol, HDL / Q000097:blood; D016000:Cluster Analysis; D015986:Confounding Factors, Epidemiologic; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000453:epidemiology / Q000503:physiopathology; D007333:Insulin Resistance; D007564:Japan / Q000453:epidemiology; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000453:epidemiology* / Q000503:physiopathology; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000453:epidemiology / Q000503:physiopathology; D011237:Predictive Value of Tests; D015995:Prevalence; D012307:Risk Factors; D014280:Triglycerides / Q000378:metabolism
D015415:Biomarkers; D001786:Blood Glucose; D008076:Cholesterol, HDL; D014280:Triglycerides; D003404:Creatinine