Original Title: Vacuna antigripal inactivada para la prevención de exacerbaciones en pacientes infantiles asmáticos

Authors' objectives: The aim of this technical consultation is to determine the effectiveness of the influenza vaccine in preventing the appearance of exacerbations in asthmatic children and adolescents.

Authors' results and conclusions: The selected guidelines (SIGN 2011, EPR-3 and GEMA), based on the same studies, coincide in that there is no enough evidence to indicate that the influenza vaccine avoids asthmatic exacerbations. Even so, there is an inconsistency between the formulated recommendations: The GEMA guideline does not make any recommendation; SIGN-2011 formulates a strong recommendation for administering the vaccine irrespective of any consideration relating to asthma, and the EPR-3 guideline recommends the consideration of the inactivated influenza vaccine in children of >6 months and adults with asthma. The selected SR from 2013 only includes a RCT that includes children. To sum up, it is considered that there is not enough evidence from RCT to show any benefit from the influenza vaccine to reduce the frequency of exacerbations in asthmatic children, as the observed differences in risks exclude an absolute difference of 6%, which is the difference pre-established as threshold for calculating the sample size in different studies. In a small number of children with confirmed influenza infections it has been seen that the vaccine could improve slightly the quality of life, but the clinical significance is uncertain. Most studies carried out on adults suggest that the vaccine seems to be quite safe as it does not show differences in exacerbations, hospitalisations or in other pulmonary dysfunction results and the use of resources during the first days following its administration both in children and adults with asthma. Contextualization/Discussion There is low quality evidence with an uncertain benefit-risk balance on the efficiency of the inactivated influenza vaccine in asthmatic children. It is believed that the recommendation of professionals would determine the decision of family members concerning the use of this preventive treatment and that its administration in all asthmatic children would involve a major increase in resources. Nevertheless, a number of different organisations in our environment maintain their recommendation in favour of the influenza vaccine in asthmatic children. Conclusions The existing scientific evidence concerning the effectiveness of using the inactivated influenza vaccine in order to prevent the exacerbations and their complications in the paediatric population with asthma is of low quality and is non-conclusive in order to define its effectiveness in the aforementioned population. New long-term studies are required to evaluate the effectiveness and/or the efficiency of the influenza vaccine in the asthmatic child population.

Authors' methods: The clinical question posed in this technical consultation was structured according to the PICO format. A search of CPGs was carried out in a number of different databases and guideline repositories, as well as a systematic search of systematic reviews (SR) and randomized clinical trials (RCT) in the Cochrane library, CRD, Medline and Embase. The CPGs quality was assessed using the AGREE II instrument and the quality of SRs using the AMSTAR instrument. Individual studies were evaluated by means of specific check lists for each type of study design, in the case of ECAs, the Cochrane Risk of Bias. The quality of the body of evidence was evaluated following the GRADE system, and for this reason the relevant outcomes were defined and their importance was rated on a scale of 1 to 9 (from least to greatest importance). The evidence was summarised for each outcome and the quality of the evidence was assessed considering the following criteria established by GRADE: limitations in the study design or execution, inconsistent results, indirectness, imprecision and publication bias. Where appropriate, the strength of association, the presence of a doseresponse gradient and the consideration of potentia confounding factors were also considered. In order to assess the overall quality of the evidence found for the question, the quality of the critical outcome with the lowest quality level was taken into account.

Project Status: Completed

Year Published: 2014

URL for published report: https://www.euskadi.eus/contenidos/informacion/2014_osteba_publicacion/es_def/adjuntos/Vacuna_antigripal_inactivada.pdf

English language abstract: An English language summary is available

Publication Type: Other

Country: Spain

Organisation Name: Basque Office for Health Technology Assessment

Contact Address: C/ Donostia – San Sebastián, 1 (Edificio Lakua II, 4ª planta) 01010 Vitoria - Gasteiz

Contact Name: Lorea Galnares-Cordero

Contact Email: lgalnares@bioef.eus

Copyright: <p>Osteba (Basque Office for Health Technology Assessment) Health Department of the Basque Government</p>