Mortality after broad- versus narrow-spectrum antibiotic treatment for patients with nursing and healthcare-associated pneumonia: A nationwide retrospective cohort study.

BACKGROUND

Nursing and healthcare-associated pneumonia (NHCAP) is defined as pneumonia occurring in individuals with frequent healthcare contact, such as residents of care facilities or patients with impaired activities of daily living. The effectiveness of broad-spectrum antibiotics in treating NHCAP remains unclear.

OBJECTIVE

To compare clinical outcomes between broad- and narrow-spectrum antibiotic treatments in patients with NHCAP using a nationwide inpatient database.

METHODS

Patients diagnosed with NHCAP between April 2014 and March 2022 were identified from the Diagnosis Procedure Combination inpatient database in Japan. Patients were categorised into those receiving broad-spectrum antibiotics (antipseudomonal penicillins, antipseudomonal cephalosporins, and carbapenems) and those receiving narrow-spectrum antibiotics (third-generation cephalosporins and penicillin plus β-lactamase inhibitor combinations). Instrumental variable analysis using hospital preference for broad-spectrum antibiotics was conducted to compare 30-day in-hospital mortality. A subgroup analysis was performed for patients with ≥3 risk factors for antibiotic-resistant pathogens.

RESULTS

Among 828,283 eligible patients, 24.8% received broad-spectrum antibiotics, while 75.2% received narrow-spectrum antibiotics. Instrumental variable analysis showed that broad-spectrum antibiotic use was not associated with 30-day in-hospital mortality (10.0% vs. 10.0%; risk difference, 0.0%; 95% confidence interval, -0.7% to 0.8%) compared with narrow-spectrum antibiotic use. The subgroup analysis of patients with three or more risk factors for antibiotic-resistant pathogens, broad-spectrum antibiotic use was also not associated with 30-day mortality (10.5% vs. 11.0%; risk difference, -0.6%; 95% confidence interval, -2.5% to 1.3%).

CONCLUSIONS

Broad-spectrum antibiotic use was not associated with short-term in-hospital mortality in patients with NHCAP, underscoring the importance of individualized antibiotic selection based on patient-specific risk factors.