Community acquired pneumonia (CAP) is the most common, potentially fatal infectious disease in the western industrialize world. The mortality rate is between 5% and 15% despite the development of new antibiotics, better diagnostic tools, and improved intensive care services. This mortality rate has not changed substantially in the last 60 years. What is of additional interest is that 50% of the deaths associated with CAP are due to other causes, most specifically cardiovascular disease (CVD).
CAP increases the risk of death significantly in the first 30 days and this risk extends in a substantial way for the next year. There is still an increased risk after 5 years. The most common heart related complication is heart failure followed by acute coronary syndrome (heart attack) and heart rhythm problems.
What could be the reason for these findings? Pneumonia is an inflammatory process and so is atherosclerosis (hardening of the arteries). Respiratory infections create a tremendous local inflammatory response in the lungs, but are also associated with whole body inflammation as well. This inflammatory process can have serious detrimental effects on heart function resulting in poor heart muscle function with consequential heart failure.
The presence of unrecognized heart disease, particularly in the elderly, may lead to serious complications where pneumonia is the sentinel event which unmasks a serious life limiting condition. Prevention with vaccines, early and accurate diagnosis, and prompt treatment are all ways we can help prevent the cardiovascular consequences associated with community acquired pneumonia.