Cardiovascular diseases associated with influenza infection: protocol for a systematic review and meta-analysis

Background Cardiovascular diseases represent important diagnoses that can become fatal if an early and adequate management is not carried out. Since 1930, a possible relationship between these events and influenza virus infection has been proposed. Objectives To determine the association between cardiovascular diseases and previous infection by influenza virus. Materials and methods We propose to do a systematic review and meta-analysis according to PRISMA. In order to do so, we will perform an electronic search in the databases of EMBASE, PubMed, Global Index Medicus, Google Scholar and Cochrane Library. Articles will first be selected according to their respective titles and abstracts; and subsequently, the full text of each article will be evaluated. Both phases will be executed by 4 authors. The extracted data will include study details, study methodology and results. The quality of the studies will be verified using standardized tools according to the study design and we will evaluate possible biases. In addition, a meta-analysis of the association measures will be performed using Cochrane’s Software Review Manager 5.4.1 and we will use the GRADE tool to assess the certainty of the results obtained from the analyzed studies. Results We will publish the results of this systematic review and meta-analysis in a peer-reviewed journal. Conclusions This systematic review will provide more up-to-date evidence compared to previous work on the association between laboratory-confirmed influenza and cardiovascular diseases.