Metabolic syndrome: Why the controversy?

As originally conceived, the metabolic syndrome defined a clustering of cardiovascular disease risk factors with insulin resistance as the common, underlying pathophysiologic determinant. The definition of the syndrome has evolved since then, with several groups proposing somewhat differing definitions. Partly, this has been motivated by efforts to make the syndrome a clinically useful entity. However, recent articles have called the clinical use of the metabolic syndrome into question. In this review, some of these concerns and counterarguments for the continued use of the metabolic syndrome are reviewed.     

Metabolic inflexibility in skeletal muscle: a prelude to the cardiometabolic syndrome?

Peripheral insulin resistance, which is largely dependent on skeletal muscle, is closely linked to the development of the cardiometabolic syndrome. Metabolic flexibility is the capacity for skeletal muscle to acutely shift its reliance between lipids or glucose during fasting or postprandial conditions. Obese and insulin-resistant individuals display elevated intramuscular lipids, impaired vasculature function, decreased fatty add oxidation during fasting, and reduced postprandial glucose metabolism. Impairments in metabolic flexibility are linked to physical inactivity, excess energy intake and obesity, and genetic predisposition. Each of these factors precludes the development of insulin resistance and the cardiometabolic syndrome by mechanistic links that are not fully understood.     

Metabolic syndrome

Corresponding author:Charles Shaeffer,MD,Desert Cardiology Center,Eisenhower Medical Center,39000 Bob Hope Drive,Rancho Mirage,CA92270-3221,USATel:760-346-0182;E-mail:sewfari @ earthlink.net     

Metabolic syndrome: Perception or reality?

Metabolic syndrome is associated with increased risk for type 2 diabetes and cardiovascular disease. It has garnered considerable clinical and research interest as a potential target to reduce cardiovascular risk in addition to the classical risk factors. Whether it exists as a distinct clinical entity has become a subject of controversy and debate. This review appraises the evidence in support of or against recognizing metabolic syndrome as a clinical condition that requires therapeutic intervention. Proper evaluation of cardiovascular disease risk should start with consideration of traditional risk factors using validated tools, such as the short-term 10-year Framingham risk score. Individuals with abdominal obesity should be further assessed for associated cardiometabolic risks. Global cardiovascular disease risk should take into consideration not only short-term but also lifetime risks.