METABOLIC SYNDROME CRITERIA: CAUSE VERSUS EFFECT OF CARDIOMETABOLIC DISEASE


T. Barry Levine, M.D., Drexel University College of Medicine, Philadelphia, PA, USA

Although metabolic syndrome (MetSyn)-criteria provide a convenient tool to recognize individuals at increased cardiometabolic disease-risk, they appear haphazard, mixing descriptors of body-phenotype with lab-tests and a vascular condition. Are MetSyn-criteria causes or effects? Can they explain MetSyn-pathophysiology and guide therapy?

Insulin resistance (IR) underlies MetSyn. IR arises in response to stressors. Inflammatory/oxidative stress-pathways underlie IR-mechanisms. IR is the metabolic expression of inflammation. IR terminates anabolic/vascular insulin-signaling in non-essential organs and engenders an insulin-resistant catabolic state to fuel essential immune cells. Concurrently, mitogenic insulin-signaling is enhanced by secondary hyperinsulinemia. Barring reversal of precipitating factors, IR begets further IR.

The acute survival-benefit of IR-pathways is lost when this acute fix becomes protracted. IR and underlying mechanisms erode intracellular/intramitochondrial biochemical pathways, eventually engendering cell senescence, cell drop-out, tissue dysfunction, physiologic aging, progressing to age-related chronic disease irrespective of chronological age, as reflected in MetSyn and comorbidities.

Causes and effects of IR can be dissected from MetSyn-criteria:

IR-related disease-pathways and target-tissues require a multifaceted approach, comprising antioxidant, anti-inflammatory, stress-relieving therapeutic-lifestyle-changes (TLCs) complemented by pharmacotherapies with broad-spectrum impact due to pleiotropic (antioxidant, anti-inflammatory, mitochondrioprotective, anticoagulant, vasculoprotective, antiproliferative, insulin-sensitizing) effects that comprehensively reverse IR and delay/prevent MetSyn-comorbidities.