Metabolic Syndrome

Metabolic syndrome forms a cluster of metabolic dysregulations including insulin resistance, atherogenic dyslipidemia, central obesity, and hypertension. ^[1] It refers to the co-occurrence of several known cardiovascular risk factors that are interrelated and share underlying mediators, mechanisms, and pathways, identifying a subgroup of patients at high risk of developing cardiovascular disease and type 2 diabetes. ^[2] Several different definitions of the syndrome exist, causing substantial confusion as to whether they identify the same individuals, and there is still a need to develop uniform criteria. ^[3]

The pathogenesis of the syndrome encompasses multiple genetic and acquired entities that fall under the umbrella of insulin resistance and chronic low-grade inflammation. ^[1] It is a prothrombotic and proinflammatory state characterized by increased inflammatory cytokine activity. ^[4] Sedentary lifestyles and unbalanced dietary patterns are strongly suggested to play a fundamental role in the syndrome's development. ^[5]

In a meta-analysis of global data from more than 28 million individuals, the global prevalence of metabolic syndrome varied from 12.5% to 31.4% according to the definition considered and was higher in regions and countries with higher income levels. ^[6] The clustering of abdominal obesity, dyslipidemia, hyperglycemia, and hypertension is associated with a two-fold increase in the risk of coronary heart disease and cerebrovascular disease and a 1.5-fold increase in the risk of all-cause mortality. ^[7] Raised fasting glucose is one of the five defining diagnostic components of metabolic syndrome, three of which are required to establish the diagnosis ^[8].

If left untreated, metabolic syndrome is significantly associated with an increased risk of developing diabetes and cardiovascular disease, which constitute the leading cause of morbidity and mortality worldwide. ^[1] Early diagnosis is important in order to employ lifestyle and risk-factor modification. ^[9] The Mediterranean diet is a first-line dietary strategy for the prevention and treatment of metabolic syndrome, with evidence supporting beneficial effects on its component risk factors ^[10].