Estimates of Target Population for Pneumococcal Vaccination in People over 50 years in Catalonia and Spain

Background: Published data about prevalence of distinct risk condictions for pneumococcal disease is scarce. This study investigated the prevalence of distinct risk conditions for Pneumococcal disease in Catalonian adults and stimated the potential size of target population for Pneumococcal vaccination in Catalonia and Spain. Methods: Cross-sectional population-based study that included 2,033,465 individuals >= 50 years-old assigned to the Catalonian Health Institute (Catalonia Spain) at 01/01/2015. The Catalonian Health Institute Information System for the Development of Research in Primary Care (SIDIAP) was used to idendify comorbidities and/or underlying conditions in each subject and establish potential target population for pneumoeoccal vaccination on the basis of their risk for suffering Pneumococcal infections: 1) immunocompromised subjects: 2) immunocompetents subjects with any risk condition; 3) immunocompetents subjects without risk conditions. Results: Of the 2,033,465 study subjects, 1,053,155 (51.8%) had run risk conditions, 649,014 (31.9%) had one risk condition and 331,296 (16.3%) had multiple risk conditions (11.4% in 50-64 years vs 21.2% in people >= 65 years, p<0.001; 21.8% in men vs 11.6% in women, p<0.001). Overall, 176,600 (8.7%) and 803,710 (39.5%) were classified in risk stratum 1 and 2, respectively. According to distinct risk strata considered, the target population for Pneumococcal vaccination varied between 0.2-19 million in Catalonia and 1.5-2.3 million in Spain. Conclusion: In our setting, almost fifty percent of people >= 50 years have at least one risk condition to suffert pneumococcal disease. Adult population susceptible for Pneumococcal vaccination largely varies depending on the risk stratum considered as targeted people for Pneumococcal vaccination.