Hospital morbidity due to influenza-related causes of elderly in Brazil, 1992 to 2006: actual situat, trends and impact of vaccination / Morbidade hospitalar por causas relacionadas à Influenza em idosos no Brasil, 1992 a 2006: situação atual, tendências e impacto da vacinação

AUTOR(ES)
DATA DE PUBLICAÇÃO

2008

RESUMO

Objectives. To describe the magnitude, distribution and seasonality of influenzarelated causes of hospitalization in people older than 59 years old, according to the subgroup of age, gender and place of residence in Brazil from 1992 to 2006. Methods. This is an observational, ecological and descriptive study combining the description of time series and multiple groups using data from the Hospitalization Information System of Brazil. The following conditions were considered influenzarelated causes of hospitalization in people older than 59 years old according to the International Classification of Diseases (ICD 9 and 10): influenza, pneumonia, chronic bronchitis or non-specified bronchitis and other causes of chronic obstruction of airways non-specified. The hospitalization rates for each condition were determined for three age subgroups (60 - 69 years old, 70 79 years old and 80 years old and over), gender and place of residence in Brazil from 1992 to 2006. Results. The influenza-related causes of hospitalization in the population over 59 years old in Brazil were responsible for 4.361.370 hospitalizations from 1992 to 2006 with a mean annual rate of 22 / 1.000 elderly. There was no difference in the rates for the gender but the rates increased with age being 4,2 times higher in the 80-89 years old age subgroup when compared to the 60-69 years old age subgroup. The Brazilian regions with the highest hospitalization rates were South, Center-west and South-east with the lowest rates in the North and North-east regions. Considering the year in fortnight periods, the highest rates were observed between the 9th and the 19th fortnight periods representing the months from May until August in Brazil and in its regions. The highest rates were in the 14th fortnight periods in the South, Centerwest and South-east with 34,4, 23,3 e 14,8 hospitalizations per 1.000 elderly respectively. In the North and North-east regions the highest rates were observed between the 5th and 15th fortnight periods with a peak in the 6th fortnight periods for the North region (12,4/1.000 elderly) and 10th for the North-east region (12,7/1.000 elderly). When comparing the rates of influenza-related causes of hospitalization in the period of 1992-1998 to the period of 1999-2006, before and after the introduction 16 of influenza vaccination in Brazil (1999), there was an important decrease of the hospitalization rates in Brazil and particularly in the South, South-east and Centerwest regions. Conclusions. The different epidemiological profiles of the disease and its related conditions characterized by the hospitalization rates in this study may be influenced by the demographic density, the age and the climatic conditions. The decrease of the hospitalization rates after 1999 in Brazil and some of Its regions can be related to the vaccination against influenza. More studies are necessary to confirm the trends of hospitalizations rates and to determine the causal relation to influenza vaccination

ASSUNTO(S)

hospitalizations influenza elderly saude publica vacina contra influenza influenza vaccine epidemiologia idoso morbidade hospitalar sazonalidade influenza seasonality epidemiology

ACESSO AO ARTIGO

Documentos Relacionados