Obesity Paradox as a Component of Reverse Epidemiology in Heart Failure

Abstract

We read with great interest the article by Curtis et al¹ on the inverse relationship between BMI and survival in patients with HF due to systolic dysfunction. We were pleased to see that the findings of this study further support our respective groups initial descriptions of an inverse association between BMI and mortality in this patient population.^2-4 However, it is important to note that BMI is not the only conventional cardiovascular risk factor with a paradoxical association with clinical outcomes in patients with HF.⁴ High levels of both low-density lipoprotein and total cholesterol have been associated with a survival advantage in HF⁵ along with an inverse relationship between blood pressure and outcome in patients with HF.⁴ These consistent findings across an array of cardiovascular risk factors in patients with HF support the more inclusive term reverse epidemiology.⁴ Reverse epidemiology has also been observed in hemodialysis patients, elderly individuals, and patients with advanced malignancies, AIDS, and other chronic diseases.⁶ This means that more than 20 million individuals, including 5 million patients with HF, in the United States alone may be subject to this reverse epidemiology. We believe that this could have very important implications for public advice on health matters because conventional recommendations pertaining to the management of cardiovascular risk factors such as weight reduction or aggressive treatment of hypercholesterolemia may not be appropriate.⁶