by Nicholas Bakalar
Shingles infections are notoriously painful. They may also increase the risk of heart attacks and strokes in the weeks after an outbreak, a new study reports.
Researchers analyzed the records of 61,191 Medicare recipients with a shingles (herpes zoster) diagnosis and either a heart attack or a stroke from 2006 through 2011, comparing rates of cardiovascular events before and after a shingles attack.
They found that in the first week after diagnosis, there was a 2.4-fold increase in the rate of stroke and a 1.7-fold increase in the rate of heart attack. The difference gradually faded over six months. The findings were published in PLoS Medicine.
The exact mechanism is unclear, but the authors suggest that inflammation may lead to blood clots in people with hardening of the arteries. A similar link has been noted for respiratory diseases and other infections. Stress from the pain of shingles, the authors acknowledge, could have contributed to the effect, but they lacked the data to assess this.
Herpes zoster vaccination did not appear to change the result, but only 9 percent of people in the group had been vaccinated, not enough to reach firm conclusions about the effect of the vaccine.
“We’ve highlighted when patients with shingles may be most susceptible to vascular events,” said the lead author, Caroline Minassian, a research fellow at the London School of Hygiene and Tropical Medicine, “so this could potentially help prevent these events.”