Younger age associated with increased risk; but biological mechanism unclear
by Alexandria Bachert MPH, Staff Writer, MedPage Today July 03, 2017
Shingles attacks may increase a person’s risk of stroke and myocardial infarction, according to a large population-based cohort in South Korea.
In propensity score-matched analysis, herpes zoster reactivation — also known as shingles — raised the risks of the composite of cardiovascular events, stroke, and myocardial infarction (MI) by 41%, 35%, and 59%, respectively, compared with people without herpes zoster, reported Sung-Han Kim, MD, PhD, of the Asan Medical Center in Seoul, and colleagues in the Journal of the American College of Cardiology.
Kim explained that the public health significance of the findings is that patients now know about this epidemiological association.
“The benefit and risk communication of patients with attending physicians is needed for appropriate antiviral therapy and vaccination against shingles until further studies elucidate the effect of antiviral use or vaccination on cardiovascular outcomes,” he said in an interview with MedPage Today.
Kim and colleagues examined data from their country’s National Health Insurance Service’s “medical check-up” database — a cohort of 570,000 people who received a medical check-up that provided comprehensive social and medical information.
They followed the patients from 2003-2013 to identify those newly diagnosed with herpes zoster or shingles, stroke, and heart attack according to the relevant International Classification of Diseases-10 diagnostic codes.
Using a propensity score-matched analysis, the researchers evaluated 23,213 cases of herpes zoster with non-herpes zoster individuals.
Patients with shingles were more likely to be female, as well as to have common risk factors for stroke and heart attack, such as old age, high blood pressure, diabetes, and high cholesterol. The researchers noted that this group was also less likely to smoke, as well as have a lower alcohol intake, exercise more, and be part of a higher socioeconomic class.
Kim’s team reported that the differences of absolute incidences for stroke and MI in herpes zoster group when compared with non-herpes zoster group were 1.34 per 1,000 person-years (95% CI 0.71-1.97) and 0.80 per 1,000 person-years (95% CI 0.41-1.18), respectively.
The hazard ratios for stroke were highest in the subgroup under 40 years of age, a relatively younger population with fewer risk factors for atherosclerosis, and gradually decreased with age.
Risk for both stroke and MI were highest in the first year after the onset of herpes zoster and then tended to decrease with time. Conversely, it was evenly distributed in the non-herpes zoster group.
“While these findings require further study into the mechanism that causes shingles patients to have an increased risk of heart attack and stroke, it is important that physicians treating these patients make them aware of their increased risk,” said Kim.
Kim concluded that biologic plausibility studies are still lacking and further immunopathophysiologic mechanism studies between zoster and cardiovascular diseases are needed.