Background: Lower respiratory tract infection (LRTI) is common in the community and may result in hospitalization or death. This observational study aimed to investigate the role of antibiotics in the management of LRTI in the primary care setting in the United Kingdom.
Methods: Patients receiving a first diagnosis of LRTI during 2004 and satisfying inclusion and data quality criteria were identified in the General Practice Research Database. Factors associated with respiratory infection-related hospital admissions and death in the 3 months following the initial diagnosis were identified using Cox proportional hazards regression.
Results: Antibiotic prescribing on the day of diagnosis was associated with a decreased rate of respiratory infection-related hospital admission (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.58 to 0.92), while antibiotic prescribing in the previous 7 days (HR, 1.92; 95% CI, 1.24 to 2.96) and prior referral or hospitalization (HR, 1.48; 95% CI, 1.20 to 1.83) were associated with an increased risk of hospital admission. Female sex (HR, 0.73; 95% CI, 0.64 to 0.84), allergic rhinitis (HR, 0.48; 95% CI, 0.27 to 0.83), influenza vaccination (HR, 0.75; 95% CI, 0.65 to 0.87), prior inhaled corticosteroid use (HR, 0.63; 95% CI, 0.52 to 0.76), and antibiotic prescription on the day of diagnosis (HR, 0.31; 95% CI, 0.26 to 0.37) were associated with decreased respiratory infection-related mortality, while a Charlson comorbidity index of >or= 2 (HR, 2.24; 95% CI, 1.72 to 2.92), antibiotic prescription in the previous 7 days (HR, 1.56; 95% CI, 1.20 to 2.03), and frequent consultation (HR, 1.62; 95% CI, 1.09 to 2.40) were associated with increased mortality.
Conclusions: Antibiotic prescribing on the day of LRTI diagnosis was associated with reductions in hospital admissions and mortality related to respiratory infection. Antibiotics may help to prevent adverse outcomes for some patients with LRTI.