Respiratory viral infection in early life and development of asthma in childhood: A protocol for systematic review and meta-analysis

BACKGROUND: Respiratory viruses are the leading cause of early life wheezing that may contribute to the development of childhood asthma leading to increasing morbidity and socioeconomic burden. The aim of this review is to identify whether respiratory viral infections during first year of life were associated with development of childhood asthma. METHODS: We will search major scientific databases (MEDLINE, CINAHL, Web of Science, Cochrane Library, and ClinicalTrials.gov) using truncated and phrase-searched keywords and relevant subject headings. Observational studies including case–control studies, cohort studies, and randomized control trails published in English will be included in this review. Case reports, qualitative studies, and narrative overviews will be excluded. Exposure will be defined as laboratory-confirmed viral respiratory tract infection in the first year of life and outcome will be defined as development of asthma between ages 5 and 18 years. Effect sizes in bivariate and multivariate analyses will be presented as odds or prevalence ratios. We will explore for heterogeneity of the standard errors across the studies, and if appropriate, we will perform a meta-analysis using a random-effects model to present a summary estimate of the odds or prevalence ratios. RESULTS: This review will assess whether respiratory viral infections during first year of life increases the risk of childhood asthma development. CONCLUSIONS: This systematic review will evaluate published literature, assessing the link between early life viral infection and childhood asthma. Pooled data may provide evidence that infantile respiratory viral infection results in higher incidence of recurrent wheezing and asthma, thereby stimulating further research into the cost-effectiveness of pharmaceutical interventions such as vaccines and nonpharmaceutical interventions such as hand-washing and respiratory hygiene promotion to young children. Implementing the results of such research may then reduce the burden of acute viral respiratory infections and subsequent recurrent wheezing and asthma. SYSTEMATIC REVIEW REGISTRATION: This systematic review has been registered on PROSPERO (CRD42018105519)