Healthcare

Many experts hold the view that the reason metabolic syndrome is associated with an increase in cardiovascular risk is that most patients with the metabolic syndrome also have type 2 diabetes mellitus.

However, in the recent meta analysis results published on September 28 of the Journal of the American College of Cardiology, lead by Dr Salvatore Motillo from McGill University, Montreal, QC, show that metabolic syndrome maintain its prognostic value for cardiovascular outcomes even in the absence of type 2 diabetes mellitus.

However, whether or not the prognostic significance of the metabolic syndrome exceeds the risk associated with the sum of its individual components, other prospective study should be established to answer it.

Overall, in this meta analysis as updates previous meta-analyses (included studies published prior to 2005), also included an additional 87 studies which involved 951,083 patients, showed in patients with metabolic syndrome had 2-fold increase in risk cardiovascular disease, cardiovascular mortality, myocardial infarction (MI), and stroke among patients with metabolic syndrome, and 1.5 fold increase in risk for all-cause mortality.

Based on the National Cholesterol Education Program (NCEP), released in 2004, the metabolic syndrome defined as having three or more of the following five cardiovascular risk factors;
- central obesity (waist circumference; men >102 cm and women >88 cm),
- elevated triglycerides (>150 mg/dL),
- low HDL (men <40 mg/dL and women 130/>85 mm Hg), and
- elevated fasting glucose (>110 mg/dL).

The modified NCEP and modified revised NCEP definitions use measurements of body mass index (BMI) (typically BMI >30 kg/m2 or BMI >27 kg/m2 in Asian populations) to define central obesity, and lowered threshold of fasting glucose from >110 mg/dL to >100 mg/dL.

The authors point out that this is the first meta-analysis to establish the cardiovascular risk associated with the revised National Cholesterol Education Program (NCEP) definition of the metabolic syndrome. However, they found little variation in cardiovascular risk between the two definitions.

According to the authors, to determine the higher estimates of risk in women than in men, the researchers note that patient-level data are needed to confirm this finding, but mechanisms that may explain the higher risk in women include the following;
- central adiposity tends to be more pronounced in women postmenopausal than in men,
- women have a different cholesterol profile from men,
- there is evidence that elevated triglycerides are more highly associated with CAD in women than in men,
- unique factors to women, including polycystic-ovary syndrome, hormonal contraceptive use, and gestational diabetes, may be important.

The authors conclude that healthcare workers should use the metabolic syndrome to identify patients who are at particularly high risk for cardiovascular complications and that the prevention and reduction of the metabolic syndrome is essential to reduce cardiovascular disease and to extend life in the adult population.