An Obesity Paradox: Increased Body Mass Index Is Associated with Decreased Aortic Atherosclerosis
Brodsky et al. (Cardiovasc Pathol 25(6), 515–520, 2016) recently have reported that there was an unexpected and highly significant inverse correlation between body mass index (BMI) and atherosclerosis of the aortas of morbidly obese decedents (BMI >40 kg/m2). In a series of 304 decedents, 65 of whom were morbidly obese, minimal or no atherosclerosis was seen in 46 of them (70%) versus 20 (30%) who had severe atherosclerosis (P = 0.008). This obesity paradox was unexpected and raises important questions about the etiology and pathogenesis of atherosclerosis, which will be the subject of this commentary. The concept of healthy versus unhealthy adiposity may in part provide an explanation for the “obesity paradox.” Another factor that will be considered is the possible role of adipokines and their genetic determinants that may significantly reduce the risk of developing aortic atherosclerosis in morbidly obese individuals. Considering the marked variability in the pattern and extent of atherosclerosis of the aorta, hemodynamic factors and endothelial cell shear stress may be the most important determinants that might explain the obesity paradox that we have observed. Finally, the possible role of gut microbiota and inflammation as factors in the etiopathogenesis of atherosclerosis will be considered, but their importance is less clear than that of hemodynamic factors. We conclude with the remarkable finding that a 5300-year-old, well-preserved mummy of the “Iceman,” Ötzi had atherosclerotic disease of a number of major arteries and the interesting questions that this raises.
KeywordsAtherosclerosis Morbid obesity Hypertension Obesity paradox
We thank Drs. Carl “Chip” Lavie and William C. Roberts for their helpful suggestions in developing this Commentary, and Ms. Loretta Bahn for secretarial assistance in the preparation of this manuscript.
Compliance with Ethical Standards
Conflict of Interest
The authors declare no conflicts of interest relevant to this manuscript.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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