OBJECTIVE To discuss possible explanations for the obesity paradox and explore whether the paradox can be attributed to a form of selection bias known as collider stratification bias. METHOD The paper is divided into three parts. First, possible explanations for the obesity paradox are reviewed. Second, a simulated example is provided to describe collider stratification bias and how it could ...

Although obesity and the associated metabolic syndrome negatively impact on health outcomes, a paradoxical relationship between obesity and mortality has been reported for specific patient populations - the "obesity paradox". However, underlying mechanisms remain unclear and several possible explanations are being discussed. First, a true protective effect of obesity is possible, mediated throu...

There is strong relationship exist between obesity and cardiovascular disease including coronary artery disease (CAD). However, better outcomes noted in obese patients undergoing percutaneous cardiovascular interventions for CAD, a phenomenon known as the obesity paradox. In this review, we performed extensive search for obesity paradox in obese patients undergoing percutaneous coronary interve...

Obesity, a risk factor for de novo chronic kidney disease (CKD), confers survival advantages in advanced CKD. This so-called obesity paradox is the archetype of the reverse epidemiology of cardiovascular risks, in addition to the lipid, blood pressure, adiponectin, homocysteine, and uric acid paradoxes. These paradoxical phenomena are in sharp contradistinction to the known epidemiology of card...

Obesity is a growing public health problem in the general population, and significantly increases the risk for the development of new-onset heart failure (HF). However, in the setting of chronic HF, overweight and mild to moderate obesity is associated with substantially improved survival compared to normal-weight patients. Evidence exists for an "obesity paradox" in HF, with the majority of da...