The association between body mass index and outcomes in patient with sepsis and acute respiratory failure

Abstract

Background: Patients with increased body mass indices (BMIs) often present practicalproblems during their management for acute medical disorders in intensive care units. Somestudies suggested obese patients have longer ICU stays but lower in-hospital mortality rates.This study considers the effect of BMI on outcomes in patients with sepsis and respiratoryfailure.Methods: The electronic medical records of patients hospitalized between 2010 and2016 with sepsis who required mechanical ventilation were reviewed to collect demographiccharacteristics, clinical information including BMI subcategory, management requirements,and outcomes, such as mortality, ICU length of stay (LOS), and hospital LOS.Results: This study included 312 adult patients. The mean age was 59.1 ± 16.3 years;57.4% were men. The mean BMI was 29.3 ± 10.7 kg/m2. The median APACHE II score was14, 46.2 % of the patients had pulmonary infections, and 34.9% had extrapulmonary infections.The overall mortality was 42.6%. The mean LOS was 12.4 ± 11.8 days in the ICU and16.6 ± 13.6 days in the hospital. The mortality rates were 38.5% in underweight patients (BMI<18.5kg/m2), 51.1% in normal weight patients (BMI 18.5–24.9 kg/m2), 38.5% in overweightpatients (BMI 25–29.9 kg/m2), and 40.2% in obese patients (BMI >30 kg/m2). Body mass indexdid not have an independent effect on mortality after adjusting for age, gender, and APACHEII scores; however, overweight patients required more mechanical ventilation days and had anincreased LOS in the ICU and the hospital.Conclusions: This study demonstrates that patients with sepsis requiring mechanicalventilation have a high mortality rate and that BMI did not have an effect on mortality. Aprospective study which considers differences in clinical characteristics, managementrequirements, complications, and inflammatory parameters in different BMI subcategories isneeded. Overweight patients had an increased ICU and hospital LOS.