Could influenza vaccination prevent myocardial infarction, stroke and sudden cardiac death?
Acute myocardial infarction (AMI), sudden cardiac death and atherothrombotic stroke, which share a common pathogenesis involving disrupted atherosclerotic plaque and intravascular thrombosis, vary seasonally, with peak incidence in winter months. This seasonality is similar to that of upper respiratory infections, of which 38% are due to influenza. Infections such as influenza produce many biochemical, cellular, and hemostatic changes that could predispose to plaque disruption and thrombosis. Infections, particularly of the respiratory tract, often precede AMI and stroke. Four observational studies and one small clinical trial suggest that influenza vaccination can reduce the occurrence of sudden death, AMI, and stroke by approximately 50%. Influenza vaccine is very well-tolerated. With up to 16% of adults contracting influenza each year and the vaccine reducing the incidence of influenza by 50%, influenza vaccination could make a substantial public health impact on acute cardiac and n