The obesity paradox is an unexpected phenomenon where obesity seems to provide a protective effect, resulting in better survival rates for specific patient groups. This study investigates whether the obesity paradox exists in patients admitted for aortic stenosis (AS) in the United States.

We conducted a study using the 2020 National Inpatient Sample (NIS) to identify all patients admitted with a primary diagnosis of aortic stenosis (AS). We then singled out those with an ICD-10 code for obesity. To analyze associations, we employed logistic and linear regression, adjusting for potential confounders. A 2-tailed p-value of 0.05 was considered significant for our findings.

Using the 2020 National Inpatient Sample (NIS), we identified 102,615 aortic stenosis-related hospitalizations, with 18,969 (18.5%) involving obese patients. Results showed that obese patients with AS experienced reduced in-hospital mortality (aOR 0.57, 95% CI 0.42 – 0.77), increased use of mechanical ventilation (aOR 1.39, 95% CI 1.21- 1.61), and a lower likelihood of initiating hemodialysis (HD) (aOR 0.63, 95% CI 0.49- 0.79) compared to non-obese patients.

In conclusion, our findings indicate that obese patients with a primary diagnosis of AS have significantly lower odds of in-hospital mortality and hemodialysis initiation, but higher rates of mechanical ventilation compared to non-obese patients. To better understand the obesity paradox and its impact on clinical outcomes for patients with AS, further large-scale, methodologically robust studies are needed. These investigations will help uncover the underlying mechanisms and reasons for the persistence of the paradox, leading to improved patient care strategies.