Association between influenza infection and cardiovascular diseases: A systematic review and meta-analysis

Influenza infection may increase the risk of cardiovascular diseases (CVDs), but the extent of this link is uncertain. This systematic review and meta-analysis aimed to quantify the association between influenza infection and CVDs.

We conducted a comprehensive search of major databases from inception to 2024, identifying studies that investigated the association between influenza infection and CVDs. Eligible studies included cohort, case-control, and randomized controlled trials reporting on cardiovascular outcomes (acute CVDs) following influenza infection or risk of influenza infection in CVD patients (chronic CVDs). Data were extracted and pooled using random-effects models, and heterogeneity was assessed using the I ² statistic.

A total of 11 studies (15 datasets) involving 7327 participants were included in the meta-analysis. Overall, influenza infection was significantly associated with CVDs based on 10 datasets (odds ratio (OR) = 1.76, 95% confidence interval (CI): 1.02-3.03). However, the analysis of the five datasets indicated no significant association between pre-existing CVDs and an increased risk of influenza infection (OR = 0.91, 95% CI: 0.80-1.03). Subgroup analyses and meta-regression highlighted that study quality and design could significantly influence the risk of developing CVDs among patients with influenza.

This meta-analysis provides quantitative evidence that influenza infection could be a potential risk factor for subsequent cardiovascular events. These findings emphasize the need for preventive measures, including vaccination, especially in high-risk populations. Further research is needed to explore the underlying mechanisms and impact of influenza on cardiovascular outcomes.