Relationship between serotypes, disease characteristics and 30-day mortality in adults with invasive pneumococcal disease.

Purpose: Invasive pneumococcal disease (IPD) is responsible for substantial mortality and morbidity worldwide. We aimed to identify host and bacterial factors associated with 30-day mortality in 18-year-old patients hospitalized with IPD in France from 2013 to 2015.

Methods: This study analyzed data collected from consecutives IPD cases included in two parallel multi-center cohort studies: COMBAT study (280 patients with pneumococcal community-acquired bacterial meningitis) and SIIP study (491 patients with non-meningitis IPD). Factors associated with 30-day mortality were identified using logistic regression.

Results: Among the 771 enrolled patients (median age 66 years, IQR [52.0-79.7]), 592/767 (77.2%) had at least one chronic disease. Patients with meningitis were younger (60.2 vs 70.9 years; p < 0.001) and had fewer chronic diseases than those with non-meningitis IPD (73.3% vs 79.4%; p = 0.05). Non-vaccine serotypes were more frequent in meningitis patients than in those with other IPD (36.1% vs 23.1%; p < 0.001). The overall 30-day mortality was 16.7% and patients with concurrent meningitis and extra-cerebral IPD had the highest 30-day mortality rate (26.5%). On multivariate analyses, older age, history of malignant solid tumor, meningeal IPD and serotypes previously identified with high mortality potential were independently associated with 30-day mortality. Of the serotypes with high mortality potential, 80% were included in licensed (PCV13 or PPV23) vaccines.

Conclusion: We observed an effect of both host factors and pneumococcal serotypes on 30-day mortality in IPD. This highlights the need for a focused strategy to vaccinate at-risk patients.

Clinical Trial: ClinicalTrial. Gov identification number: NCT01730690.