Impact of High Body Weight on Mortality in Critically Ill Patients Receiving Meropenem for Pneumonia

Abstract

Introduction: Body size has a significant impact on pharmacokinetics of antibiotics, and leaving body size out of consideration may increase the probability of therapeutic failure. The objective of this study is to evaluate the impact of high body weight on mortality in critically ill patients who received meropenem for pneumonia. Methods: The electronic medical records of a respiratory intensive care unit (RICU) were retrospectively screened for patients with the first diagnosis of pneumonia and receiving meropenem from 2014 to 2018. Clinical variables and outcome measures were collected in patients who met inclusion criteria. Patients were assigned to quartiles based on body weight (quartile (Q) 1 <52.25 kg; Q2 52.25-65.00 kg; Q3 65.01-72.85; Q4 >72.85 kg). Logistic regression analyses were used to investigate associations between the body weight and mortality. Mortality rates were compared among different body weight quartiles. Results: Of 1,621 patients admitted to the RICU, 146 patients met the inclusion criteria. There was no significant difference in mortality of patients in different body weight quartiles. In subgroup analysis of patients receiving mechanical ventilation, there was an association between body weight and RICU mortality (odds ratio, 2.97 [1.128-7.846]; P=0.027). In Q4, mortality rate of patients who received meropenem 2 g/day was significantly higher than that of patients who received 3 g/day (69.56% vs 35.71%; P=0.047). Conclusions: There was an association between body weight and mortality in patients receiving mechanical ventilation. Compared with low-dose meropenem, high-dose meropenem might decrease mortality rate of critically ill patients with highest body weight.