Impact of Antimicrobial Resistance on In-Hospital Mortality and Length of Hospital Stay for Pneumonia: A Retrospective Cohort Study in Spain

Based on a large nationwide cohort, this study systematically analyzed the impact of antimicrobial resistance (AMR) on in-hospital mortality and length of stay among patients with bacterial pneumonia, revealing the significant clinical burden associated with AMR and providing important insights for public health policies and clinical practice.

 

Literature Overview
This study, titled 'Impact of Antimicrobial Resistance on In-Hospital Mortality and Length of Hospital Stay for Pneumonia,' published in the journal Antibiotics, reviews and summarizes clinical data from hospitalizations for bacterial pneumonia in Spain between 2017 and 2022, analyzing the impact of AMR on patient outcomes. The article provides detailed data on the epidemiology, clinical characteristics, and outcome disparities associated with AMR pneumonia, offering important evidence for antimicrobial resistance research.

Background Knowledge
Antimicrobial resistance (AMR) has become a major global public health challenge, particularly for infectious diseases such as bacterial pneumonia. Bacterial pneumonia is one of the leading causes of mortality worldwide, and pneumonia caused by AMR presents fewer treatment options, higher toxicity, and greater risk of treatment failure. Despite global action plans and national policy frameworks, AMR continues to rise, and its impact on in-hospital mortality and length of stay has not been fully quantified. This study systematically examines the clinical impact of AMR pneumonia using a national healthcare database from Spain, filling an important data gap and offering significant practical relevance.

 

 

Research Methods and Experiments
The study employed a retrospective cohort design, utilizing the Spanish RAE-CMBD national database to include adult patients hospitalized for bacterial pneumonia between 2017 and 2022. Hospitalizations were categorized into AMR and non-AMR groups based on ICD-10-CM codes. Multivariable logistic regression, Poisson regression, and propensity score matching were used to analyze the impact of AMR on in-hospital mortality and length of hospital stay, adjusting for potential confounding factors such as age, comorbidities, and ICU admission.

Key Conclusions and Perspectives

• Among 116,901 hospitalized pneumonia patients, 5.15% (6,017 cases) were identified as AMR pneumonia, with a significantly higher in-hospital mortality rate compared to the non-AMR group (18.46% vs. 10.05%, p < 0.0001)
• The median hospital stay for AMR pneumonia patients was 14 days, significantly longer than the 8 days for non-AMR patients, representing a 46% increase after adjustment (IRR 1.46)
• AMR pneumonia patients were more likely to be older, have higher comorbidity scores, and require ICU admission, with a 47% increased risk of mortality (OR 1.47)
• The primary pathogens causing AMR pneumonia were Gram-positive cocci (e.g., methicillin-resistant Staphylococcus aureus) and Gram-negative bacilli (e.g., carbapenem-resistant Enterobacteriaceae, Pseudomonas aeruginosa)

Research Significance and Prospects
This study highlights the significant clinical implications of AMR, suggesting the necessity for enhanced AMR surveillance and resource allocation. Additionally, it recommends future investigations into region-specific AMR trends, cost-effectiveness of rapid diagnostic tools, and long-term patient outcomes, including post-discharge survival rates.

 

 

Conclusion
This study reveals the severe clinical consequences of antimicrobial-resistant pneumonia, including increased in-hospital mortality and prolonged hospital stays. The findings further support the need to strengthen antimicrobial stewardship policies and the clinical implementation of rapid diagnostic tools. Future research should focus on regional AMR trends and long-term patient outcomes to provide more precise guidance for public health and clinical management.

 

Iván Oterino-Moreira, Montserrat Pérez-Encinas, Francisco J Candel-González, and Susana Lorenzo-Martínez. Impact of Antimicrobial-Resistant Bacterial Pneumonia on In-Hospital Mortality and Length of Hospital Stay: A Retrospective Cohort Study in Spain. Antibiotics.