Respiratory Viral Contribution to Acute Myocardial Infarction: A Time Series and Spatiotemporal Analysis in Victoria, Australia 2010–2022

ABSTRACT BACKGROUND Respiratory viral infections can trigger acute myocardial infarction (AMI). However, the proportion of AMI events attributable to viral respiratory pathogens is unclear. METHODS This ecological study used time-series and spatiotemporal analyses to examine population-level patterns in Victoria, Australia, from 2010 to 2022. Independent statewide admissions and laboratory datasets were obtained. Generalized additive modelling was used to analyze the temporal association between respiratory viral circulation captured by polymerase chain reaction (PCR) testing and weekly counts of AMI admissions. A Bayesian hierarchical model was used to explore spatiotemporal variation in AMI associated with respiratory viruses. RESULTS Our study included 164 283 AMI hospital admissions and 6 180 896 PCR-tested samples. An increase in any respiratory virus detection rate was significantly associated with an increased incidence of AMI (incidence rate ratio [IRR] 1.0041; 95% confidence interval 1.0015–1.0067), after adjusting for seasonality, cold temperature, and fine particulate matter air pollution. An estimated 8.7% of total AMI events may be attributable to respiratory viral triggers, constituting an average annual incidence of 16.2 per 100,000 population. Significant associations were found with specific respiratory viruses; the fractions of AMI attributable to enterovirus, influenza, and respiratory syncytial virus were 5.2%, 1.5%, and 0.9%, respectively, with figures increased during peak viral seasons. Spatiotemporal analysis revealed that the association was more pronounced in outer-metropolitan areas. CONCLUSIONS Respiratory viral triggers contribute to the incidence of AMI. Population-level infection prevention strategies, such as vaccination, may reduce the impact of respiratory viral outbreaks during peak seasons. CLINICAL PERSPECTIVE What Is New? Using time-series analysis and modern spatiotemporal techniques, we analyzed data from Victoria, Australia, to model population-level associations between AMI and respiratory viral activity and found that a recent laboratory-confirmed respiratory viral infection is associated with a higher incidence of AMI. An estimated 8.7% of total AMI events may be attributable to respiratory viral triggers, constituting an average annual incidence of 16.2 per 100,000 population. What Are the Clinical Implications? Some respiratory viral infections temporarily increase the risk of acute MI. With the existing vaccines available against influenza and respiratory syncytial virus (RSV), public health policy actions for influenza and RSV vaccination, particularly in high-growth urban areas, may help reduce the acute cardiovascular burden and health system strain.