The Effect of Antibiotic Resistance and Inappropriate Empirical Antibiotic Therapy on 3-Day and 28-Day Mortality in Bacteremic Patients in the Intensive Care Unit: 5-Year Retrospective Analysis

Abstract

Aim: The aim of this study was to examine the effects of antibiotic resistance, empirical antibiotic therapy, and comorbid diseases on 3-day and 28-day mortality in patients with bloodstream infections. Material and Methods: Files of the patients with positive blood cultures results, between January 1st, 2015, and January 1st, 2020 were analyzed retrospectively. The primary outcome was 3-day mortality and the secondary outcome was 28-day mortality. Results: A total of 515 patients, 208 (40.4%) female and 307 (59.6%) male, were included in the study. The median age of the patients was 73 (range, 18-95) years. Vancomycin resistance was detected in 8 (3.4%) of 233 gram-positive bacteria. Third-generation cephalosporin, meropenem, and colistin resistance rates of the 282 gram-negative bacteria were found to be 72.7% (n=205), 53.2% (n=150), and 9.9% (n=28), respectively. The 3-day and 28-day mortality rates were 14.4% (n=74) and 64.3% (n=331), respectively. Charlson comorbidity index score (CCIS) (p=0.001) and acute physiology and chronic health evaluation (APACHE) II score (p=0.019) were found to be risk factors for 3-day mortality. Risk factors for 28-day mortality were; age (p<0.001), CCIS (p<0.001), APACHE II score (p=0.001), chronic obstructive pulmonary disease (p=0.007), hospital-acquired infection (p=0.033), and inappropriate antibiotic therapy (p<0.001). Conclusion: There was no association between antibiotic resistance and mortality, but inappropriate antibiotic treatment was found to increase the risk of 28-day mortality. In addition, since high CCIS and APACHE II scores increase the risk of both 3-day and 28-day mortality, we think that considering these scoring systems will reduce the risk of mortality.