Current Understanding of Multiple Risk Factors as the Metabolic Syndrome: Distillation or Deconstruction

Abstract

The "metabolic syndrome" is a new term that defines the clustering of vascular risk factors, such as hyperlipidemia, obesity, elevated blood pressure, and elevated blood glucose. Controversy exists regarding the use of the term, which raises the question of whether the unique grouping of vascular risk factors adds more clinical risk then the additive effect of multiple risk factors viewed as separate but important entities. Whatever the answer, the metabolic syndrome constitutes a major public health problem with over 47 million persons in the United States meeting criteria for the metabolic syndrome. Although studies have demonstrated that the metabolic syndrome is a risk factor for overall mortality as well as cardiovascular events, the relationship between the metabolic syndrome and ischemic stroke has not been well characterized. Two large cross-sectional studies report an association between metabolic syndrome and increased risk of a history of stroke. One large multiethnic prospective study found the metabolic syndrome to be significantly associated with an increased risk of ischemic stroke after adjustment for sociodemographics and other cardiovascular risk factors. This study estimated that the metabolic syndrome may account for 19% of ischemic strokes including 30% of stroke in women and over 40% of stroke in Hispanics. Despite debate about the utility of its definition, there is evidence to suggest that the metabolic syndrome is an important risk factor for ischemic stroke, with differential effects by gender and race-ethnicity. Further, the metabolic syndrome has important clinical and public health implications by helping to easily identify individuals at greatest risk of vascular events.

Metabolic Syndrome and Physical Performance in Elderly Men: The Osteoporotic Fractures in Men Study

“…It has been debated whether the particular clustering of vascular risk factors described as MetS is multiplicative versus additive and whether this particular risk cluster confers excess health risks in addition to those of standard risk factors 7–9 . The relationship between number of MetS components and performance was mostly graded, as shown in Figure 1.…”

“…The age‐adjusted prevalence of MetS is nearly 24% in the United States 1 and increases with age; 2 in adults age 60 and older, prevalence exceeds 40% 1 . MetS increases risk for stroke, cardiovascular disease (CVD), diabetes mellitus, and mortality, 3–6 although there is widespread debate as to whether this particular clustering of risk factors is multiplicative, rather than additive, and whether it improves risk prediction for diabetes mellitus, CVD, or mortality beyond standard risk factors 7–9 . Nonetheless, it is clear that the components of MetS are important vascular risk factors that occur together more commonly than would be expected according to chance 7 …”

Multiple metabolic risk factors and mammographic breast density

“…There are racial/ethnic (hereafter racial) differences in the prevalence of specific metabolic conditions; for example, hypertension, high blood glucose and dyslipidemia are respectively more common among African American, Hispanic and White populations in the U.S. (13). Research on metabolic abnormalities and breast cancer risk in racial minorities is further warranted given the disproportionately greater prevalence and earlier age of onset of metabolic disorders in many racial minority populations (14, 15), and the potentially adverse impact of metabolic disorders on breast cancer mortality (16). The purpose of this study was to examine whether diagnoses of hypertension, diabetes and high cholesterol, individually and in combination with each other and with having an obese body size, are associated with breast density in a predominantly African American and Caribbean sample of women.…”

Role of metabolic syndrome components in human immunodeficiency virus–associated stroke

“…Metabolic syndrome (MetS) is a constellation of disorders, including abdominal obesity, atherogenic dyslipidemia, hypertension, glucose intolerance, and a prothrombotic/inflammatory state, that increase the risk of cerebrovascular disease (Boden-Albala, 2006). Having just a single condition is not diagnostic of MetS, but does increase the overall risk of stroke (Bonora, 2006).…”