Investigating the Obesity Paradox: Patient Outcomes in Common Cardiac Procedures with Obesity

Abstract

BackgroundThe ``obesity paradox'' is a surprising phenomenon where obesity appears to provide a protective benefit, resulting in better survival rates in certain patient groups. This paradox has been observed in patients undergoing procedures like PCI, CABG, and TAVR for heart conditions. Obese patients typically show improved short- and long-term outcomes compared to non-obese or underweight individuals. This study aimed to investigate the impact of obesity on in-hospital mortality rates for US patients receiving these cardiac procedures. MethodsIn this study, we examined the 2020 National Inpatient Sample (NIS) to identify obese patients (BMI > 30) undergoing PCI, CABG, and TAVR. Using logistic and linear regression, we analyzed associations while accounting for potential confounders. A 2-tailed p-value of 0.05 was considered statistically significant for our findings. ResultsDuring 2020, a total of 331,520 hospitalizations were recorded for PCI, 153,744 for CABG and 77,230 for TAVR. Upon adjusting for variables such as age, race, gender, hospital bed size, location, teaching status, insurance coverage, income level, and Elixhauser comorbidities; we observed that obesity was associated with a reduced rate of in-hospital mortality for PCI (aOR 0.37, 95% CI 0.31 – 0.44), CABG (aOR 0.54, 95% CI 0.44- 0.65), and TAVR (aOR 0.45, 95% CI 0.27- 0.73) (Figure 1). ConclusionOur study revealed that obese patients admitted for PCI, CABG, or TAVR had significantly lower in-hospital mortality risk. To better understand the obesity paradox, larger, robust studies are needed, which will uncover underlying mechanisms, enhance understanding, and inform improved patient care strategies.