ROLE OF OBESITY IN THE PROGNOSIS OF COMMUNITY-ACQUIRED BACTERIAL PNEUMONIA: A SYSTEMATIC REVIEW AND META-ANALYSIS
Community-acquired pneumonia; Bacterium; Body mass index; Obesity; Prognosis; Mortality; Infection.
Introduction: Obesity is associated with comorbidities that considerably increase the risk of acquiring infections, especially community-acquired pneumonia (CAP) caused by bacteria. Paradoxically, some studies indicate that excess adiposity may be directly related to better survival in patients hospitalized with bacterial pneumonia. Objectives: In this context, the objective of this study was to determine the real impact of body mass index (BMI) on mortality from bacterial CAP through a systematic review and meta-analysis. Methods: Studies were searched in five databases. After selection according to the established eligibility criteria, the selected articles were read in full and the variables of interest were extracted. The 30-day and 90-day bacterial CAP mortality were used to estimate the pooled odds ratio using the Mantel-Haenszel statistical method in the Review Manager (RevMan)® 5.3 software. The heterogeneity of the primary data was analyzed using the I2 test. Results: Nine studies, which together included 25,398 patients diagnosed with bacterial CAP (10,800 controls, 7,486 overweight and 7,112 obese), were selected for this systematic review. Patients with normal weight have a higher risk of 30-day mortality from bacterial CAP compared to overweight patients (odds ratio:1.28; p-value <0.00001; I2=0%) and obese patients (odds ratio: 1.83; p-value <0.00001; I2=0%). Similarly, in the meta-analysis of the 90-day lethality, normal-weight patients also had a worse prognosis when compared to obese patients (odds ratio: 1.79; p-value <0.00001; I2=0%). Conclusion: Obesity stands out as an important protective factor against death from bacterial CAP.