Wayne H.-H. Sheu, M.D., Ph.D., Chen-Huan Chen, M.D.1, Division of Endocrinology and Metabolism, Department of Medicine, Taichung Veterans General Hospital, Taichung, Taiwan, 1Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan

According to the NCEP Adult Treatment Panel III report, subjects with the metabolic syndrome can be identified based on the presence of any three of the five easily obtainable components, namely, abdominal obesity, high blood pressure, high triglyceride, low high-density lipoproteinemia, and high plasma glucose. The so-identified subjects with the metabolic syndrome have a very high risk of developing diabetes and a moderate risk of developing cardiovascular diseases in the absence of diabetes [1-3]. Furthermore, the presence of the components of the metabolic syndrome in patients with diabetes also added to the cardiovascular risk. In fact, a recent report indicated that the presence of metabolic syndrome was associated with an increased risk of incident cardiovascular diseases 5 years after diagnosis of type 2 diabetes [4]. These findings support the hypothesis that there is a common underlying pathophysiology (likely to be insulin resistance and/or abdominal obesity) responsible for the individual components, the clustering of the components (metabolic syndrome), the genesis of diabetes plus metabolic syndrome, and cardiovascular diseases.

Previous studies have indicated the predictors of diabetes and/or cardiovascular diseases, and showed that, in general, the more components of metabolic syndrome an individual has, the greater the risk he or she has of developing diabetes and/or cardiovascular diseases [2,3]. However, there is scant data on the effects of different predictors of diabetes alone, metabolic syndrome alone, and diabetes plus metabolic syndrome in a prospective cohort. In our report [5], subjects who were free of diabetes and metabolic syndrome at enrollment (1,501 men, 2,128 women with mean age 46.7 ± 11.0 years) (mean ± SD) were followed up for 10 years (range 8-10 years). The incidence rate of diabetes was 7.8% (9.8% in men and 6.3% in women, respectively), and that of metabolic syndrome was 24.2% (23.4% in men and 24.7% women, respectively). The incidence rate of diabetes plus metabolic syndrome was 5.7% in men and 4.7% in women, respectively. After adjustment for related covariable factors, each component of metabolic syndrome in women, and higher triglyceride and greater waist circumference in men, independently predicted incident diabetes plus metabolic syndrome in these subjects as compared with those who remained free of diabetes and metabolic syndrome.

Our findings suggest that several components of metabolic syndrome are precursors for diabetes plus metabolic syndrome. In particular, high waist circumference and high serum triglyeride level are potentially useful red flags for both men and women. Although other markers may also be predictive of diabetes and/or cardiovascular diseases, such as circulating level of C-reactive protein (CRP) and adiponectin [6-8], the simple, clinically identifiable components of the metabolic syndrome recommended by both ATP III and IDF, may turn out to be the most useful markers. Identification of individuals who are at risk of developing diabetes plus metabolic syndrome, patients with the highest risk for future cardiovascular risk, may help to provide opportunities to intervene earlier.

References

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