Evaluating CMR

Differences between existing guidelines

As described in previous sections, there are no gold standard criteria for clinical diagnosis of the metabolic syndrome. Since proposed criteria differ between organizations and, more importantly, in their underlying rationale, the same individuals are not consistently identified with the metabolic syndrome when different screening tools are used. For instance, both NCEP-ATP III and IDF criteria include waist circumference. However, while NCEP-ATP waist circumference criteria are 102 cm for men and 88 cm for women, IDF criteria use much lower cut-offs that are also ethnic-specific (both organizations focused on the relationship between body mass index (BMI) and waist circumference to determine waist circumference cut-offs (6)). For example, waist circumference cut-off values for Europid men and women are 94 cm and 80 cm, respectively. As described in section “Comparison of Screening Tools,” screening tools for clinical diagnosis of the metabolic syndrome vary from one organization to another. This in turn provides individuals/organizations with fodder to criticize the use of the metabolic syndrome as a clearly defined condition (7). For instance, with NCEP-ATP III metabolic syndrome criteria, there are 10 different combinations of criteria for diagnosing the metabolic syndrome. It is reasonable to believe that not all these combinations carry equivalent CVD risk.

The joint statement from the ADA and EASD also questioned the clarity of existing criteria. According to initial NCEP-ATP III and WHO criteria, the respective cut-off values for elevated blood pressure were ≥ 130/85 mmHg and ≥ 140/90 mmHg.