Impact of pre-hospital antibiotic therapy on mortality in invasive meningococcal disease: a propensity score study

The role of pre-hospital antibiotic therapy in invasive meningococcal diseases remains unclear with contradictory data. The aim was to determine this role in the outcome of invasive meningococcal disease. Observational cohort study of patients with/without pre-hospital antibiotic therapy in invasive meningococcal disease attended at the Hospital Universitari de Bellvitge (Barcelona) during the period 1977–2013. Univariate and multivariate analyses of mortality, corrected by propensity score used as a covariate to adjust for potential confounding, were performed. Patients with pre-hospital antibiotic therapy were also analyzed according to whether they had received oral (group A) or parenteral antibiotics (early therapy) (group B). Five hundred twenty-seven cases of invasive meningococcal disease were recorded and 125 (24%) of them received pre-hospital antibiotic therapy. Shock and age were the risk factors independently related to mortality. Mortality differed between patients with/without pre-hospital antibiotic therapy (0.8% vs. 8%, p = 0.003). Pre-hospital antibiotic therapy seemed to be a protective factor in the multivariate analysis of mortality (p = 0.038; OR, 0.188; 95% CI, 0.013–0.882). However, it was no longer protective when the propensity score was included in the analysis (p = 0.103; OR, 0.173; 95% CI, 0.021–1.423). Analysis of the oral and parenteral pre-hospital antibiotic groups revealed that there were no deaths in early therapy group. Patients able to receive oral antibiotics had less severe symptoms than those who did not receive pre-hospital antibiotics. Age and shock were the factors independently related to mortality. Early parenteral therapy was not associated with death. Oral antibiotic therapy in patients able to take it was associated with a beneficial effect in the prognosis of invasive meningococcal disease.