A new systematic review published in the Journal of the American Heart Association reveals that both acute and chronic viral infections can significantly increase the risk of cardiovascular disease, including heart attack and stroke. The analysis, which screened over 52,000 publications and included 155 high-quality studies, found that influenza and COVID infections can raise the risk of heart attack or stroke as much as three- to five-fold in the weeks following the initial infection. Chronic infections such as HIV, hepatitis C, and the varicella zoster virus (which causes shingles) were associated with long-term elevations in cardiovascular risk.
According to the research, people are four times more likely to have a heart attack and five times more likely to have a stroke in the month after laboratory-confirmed influenza. For COVID, the risk of heart attack and stroke is three times higher in the 14 weeks following infection, with the risk remaining elevated for up to a year. The immune response to viral infections, which includes inflammation and increased blood clotting, is believed to contribute to these risks. Inflammation plays a key role in the development and progression of cardiovascular disease by promoting plaque formation and rupture in arteries.
For chronic infections, the review found a 60% higher risk of heart attack and 45% higher risk of stroke in people with HIV, a 27% higher risk of heart attack and 23% higher risk of stroke in those with hepatitis C, and a 12% higher risk of heart attack and 18% higher risk of stroke in individuals who had shingles. Lead author Kosuke Kawai, Sc.D., an adjunct associate professor at the David Geffen School of Medicine at UCLA, noted that while the risks are lower for chronic infections compared to acute ones, they persist for longer periods and affect large populations. For instance, shingles affects about one in three people in their lifetime, translating into a substantial number of excess cardiovascular cases.
The findings underscore the potential role of vaccination in reducing cardiovascular disease risk. A 2022 review cited in the study found a 34% lower risk of major cardiovascular events among participants receiving a flu shot in randomized clinical trials compared to those receiving a placebo. The American Heart Association recommends that individuals, especially those with existing cardiovascular disease or risk factors, consult with healthcare professionals to discuss appropriate vaccines, including those for influenza, COVID, and shingles. More information on vaccine recommendations is available at heart.org.
The researchers noted that the study was based on observational studies, which have limitations, and that more research is needed to understand links between other viruses like cytomegalovirus, herpes simplex 1, dengue, and human papillomavirus and heart disease risk. The full manuscript is available online at JAHA.
