Obesity survival paradox in patients hospitalized with community-acquired pneumonia. Assessing sex-differences in a population-based cohort study

Abstract

To assess the effect of obesity status (no obesity/obesity/ morbid obesity) on hospital outcomes (length of hospital stay [LOHS] and in-hospital mortality [IHM]), among patients hospitalized with community-acquired pneumonia (CAP) and according to sex. We conducted a retrospective cohort study based on national hospital discharge data of all subjects aged≥ 18 years hospitalized with CAP in Spain from 2016 to 2019. We identified 519,750 hospital discharges with CAP. The prevalence of obesity was 6.38% and 1.78%. for morbid obesity. The mean age was higher for patients without obesity followed by those with obesity and morbid obesity (74.61, 72.5 and 70.2 years respectively; p<0.001). The mean number of comorbidities was similar for patients with obesity and morbid obesity (2.30 and 2.29) and significantly higher than for non-obese individuals (2.10). The crude IHM was higher among the non-obese patients (12.71%) followed by those with morbid obesity (8.56%) and obesity (7.72%), without finding differences between men and women. Among men, after multivariable logistic regression analysis, the probability of dying in the hospital was significantly lower for those with obesity (Adjusted-OR 0.59;95%CI 0.55-0.63) and morbid obesity (Adjusted-OR 0.62;95%CI 0.54-0.71) compared with non-obese. The protective effect of obesity (Adjusted-OR 0.71;95%CI 0.67-0.75) and morbid obesity (Adjusted OR 0.73;95%CI 0.66-0.8) was also observed among women. Obese and obesity morbid patients with CAP have a lower risk of IHM than non-obese patients, without sex differences in this association. These data confirm the existence of the obesity paradox in this patient population.