January 3, 2014
Can Childhood Chickenpox Lead To A Stroke Later In Life?
Having the chickenpox as a child can be a highly unpleasant experience, and getting over the illness may not be the end of the ordeal, as the chickenpox virus can lie dormant in nerve cells for years, only to cause painful shingles decades later.
A new study in the journal Neurology has found that adults who contract shingles may have a higher risk of a stroke years later."Anyone with shingles, and especially younger people, should be screened for stroke risk factors," said study author Dr. Judith Breuer, a virology professor at University College London. "The shingles vaccine has been shown to reduce the number of cases of shingles by about 50 percent. Studies are needed to determine whether vaccination can also reduce the incidence of stroke and heart attack.”
“However, what is also clear is that factors that increase the risk of stroke also increase the risk of shingles, so we do not know if vaccinating people can reduce the risk of stroke per se,” Breuer added. “Current recommendations are that anyone 60 years and older should be vaccinated. The role for vaccination in younger individuals with vascular risk factors needs to be determined.”
By analyzing retrospective data on nearly 110,000 shingles cases and over 210,000 controls, the study team found that people between the ages of 18 to 40 who had shingles were more likely to have a stroke, heart attack, transient ischemic attack (TIA) or signs of a stroke, years later than people who had not had the painful illness.
More specifically, people under 40 had a 74 percent higher stroke risk if they had had shingles, after considering confounding factors. People in the study under 40 were 2.4 times more likely to have a TIA and 50 percent more likely to have a heart attack if they had shingles.
People over 40 who had shingles had a higher risk of heart attack or TIA, but not a stroke, than those who had not had shingles. These individuals only had a 15 percent greater risk of a TIA and 10 percent greater risk of a heart attack if they had shingles.
The UK-based study team noted that stroke rates have dropped 30 percent in Great Britain over the past decade, most likely due to physicians increased screening of older patients for risk factors.
"By contrast, in those aged 45 years or younger, in whom these policies have not been implemented, the incidence of stroke has remained unchanged over the same time period,” they wrote in their report.
"BMI, smoking status, and cholesterol levels were recorded less frequently in the notes of those younger than 40 years,” the team wrote about the data used in their study. The researcher took this as a sign that physicians were less focused on these factors in their younger patients.
The new study confirms the findings of a similar study published in July by the journal PLOS ONE. That study, which was based in Denmark, found shingles-related stroke or cardiovascular event risk is highest in people younger than 40.