Relationship between annual influenza vaccination and winter mortality in diabetic people over 65 years.

BACKGROUND: Influenza is an important cause of morbidity and mortality in older people, especially in those with some high-risk conditions such as diabetes mellitus. This study assessed the relationship between influenza vaccination status and winter mortality among diabetics 65 y and over during four consecutive influenza seasons. METHODS: Population-based cohort study including 2,650 community-dwelling individuals 65 y or older with diabetes mellitus followed between January 2002 and April 2005 in Tarragona, Spain. Influenza vaccination status was evaluated every year of the study and the primary endpoint was considered all-cause death during the study period. Deaths were classified as occurring within influenza periods (January-April) or non-influenza periods. The relationship between vaccination and winter mortality was evaluated by multivariable discrete-time hazard models. RESULTS: Influenza immunization was associated with a reduction of 33% (95% confidence interval: 4-53) in the adjusted risk of all-cause mortality throughout the overall influenza periods 2002-2005. The attributable risk to vaccination in reducing mortality was 13.5 per 100,000 person-weeks within influenza periods, estimating that one death was prevented for every 435 annual vaccinations. CONCLUSION: Our data confirm the benefit of influenza vaccination in reducing mortality and supports the strategy of annual vaccination in diabetics aged at least 65 y.

Effect of influenza vaccine status on winter mortality in Spanish community-dwelling elderly people during 2002-2005 influenza periods.

This study assessed the relationship between the reception of conventional inactivated influenza vaccine and winter mortality in a prospective cohort that included 11,240 Spanish community-dwelling elderly individuals followed from January 2002 to April 2005. Annual influenza vaccine status was a time-varying condition and primary outcome was all-cause death during study period. Multivariable Cox proportional-hazard models adjusted by age, sex and co-morbidity were used to evaluate vaccine effectiveness. Influenza vaccination was associated with a significant reduction of 23% in winter mortality risk during overall influenza periods. The attributable mortality risk in non-vaccinated people was 24 deaths per 100,000 persons-week within influenza periods, the prevented fraction for the population was 14%, and one death was prevented for every 239 annual vaccinations (ranging from 144 in Winter 2005 to 1748 in Winter 2002).

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.