Estimated hospitalization rate for diseases attributable to Streptococcus pneumoniae in the Veneto region of north-east Italy

Background. Streptococcus pneumoniae (SP) is a major cause of morbidity and mortality worldwide in all age groups. Serious diseases often caused by pneumococci include pneumonia, meningitis and bacteremia. Objective. The aim of this work was to estimate the hospitalization rate for SP in the Veneto region by investigating pneumococcal-related discharges. Material and methods. This was a retrospective study based on hospital discharge data collected from 2008 to 2012 in the Veneto Region (north-east Italy). All hospitalizations for diseases potentially associated with SP were identified by searching the hospital discharge records, then the proportions of hospital admissions for pneumonia, meningitis and septicemia attributable to the infection were calculated. Comorbidities were also graded according to the Charlson Comorbidity Index (CCI). Data were analyzed using the chi square test and Student's t-test for unpaired data, as appropriate. Significant trends over the years considered were examined in terms of average annual percent changes (AAPC). A p value b0.05 was considered significant. Results. We identified 62,946 hospital discharge records concerning diseases potentially associated with SP. Among them, the proportion of SP-related hospital admissions (SP-HA) was estimated to be 23,089 (37.2%). The estimated incidence of SP-HA was 94.0/100,000 population (102.8/100,000 in males and 85.6/100,000 in females; p b 0.01): 89.0 for pneumonia, 0.9 for meningitis, and 4.1 for septicemia. The incidence of SP-HA was higher in children and the elderly, and the overall fatality rate was 11.0%. The overall economic burden of SP-HA during the period considered was around €14.8 million a year, with an average cost of €3120 per hospitalization. Conclusion. This study shows that hospitalization for SP-related disease has a considerable impact on the health services, especially as far as children and the elderly are concerned.