Evolution of vaccination rates after the implementation of a free systematic pneumococcal vaccination in Catalonian older adults:: 4-years follow-up

Background: The systematic vaccination with 23-valent polysaccharide pneumococcal vaccine (PPV) was introduced as a strategic objective of health for all the people over 65 in Catalonia in 1999. We analysed the evolution of the pneumococcal vaccination rates from 2000 to 2003. Methods: We conducted a retrospective population-based study including all the individuals 65 years or older assigned to 8 Primary Care Centres (PCCs) in Tarragona ( Catalonia, Spain), who figured in the administrative population databases on 31 December 2003 ( n = 10,410 persons). We assessed whether every person had received PPV during the last four years ( 2000 to 2003) or whether they had received it before January 2000. Data sources were the computerised clinical records of the 8 participating PCCs, which included adult vaccination registries and diagnoses coded of International Classification of Diseases 9th Review Results: The overall vaccination uptake increased to 38.6% at the end of 2000. Global accumulated coverages increased more slowly the following years: 44.4% in 2001, 50.9% in 2002, and 53.1% at the end of 2003. Vaccine uptake varied significantly according to age (46.7% in people 65 - 74 years-old, 60.9% in people 75 years or more; p < 0.001) and number of diseases or risk factors (DRFs) for pneumonia (47.1% vaccinated in people without DRFs, 56.8% in patients with one DRF, and 62.2% in patients with two or more DRFs; p < 0.001). The highest coverages were observed among those patients with: diabetes (65.9%), active neoplasia (64.8%), history of stroke (63.7%), and chronic lung disease (63.5%). The lowest uptake was observed among smokers (48.7%). Discussion: The pneumococcal vaccination coverage increased quickly after the introduction of the recommendation for free vaccination in all the elderly people ( with and without risk factors), but two years after the improvement the coverage became stable and increased slowly.