If you've ever had chickenpox, the virus still lives in your body and it can be reactivated to become a case of shingles — a painful rash that occurs in a band on one side of your face or body. A new study has shown that people who get shingles have an increased risk of heart attack and stroke. The risk was highest in people under 40 years old, people who usually aren't at risk for heart disease.
Over a 10 year period, researchers at the University of Ulsan College of Medicine in the Republic of Korea followed the health of half a million patients. During that time, about 4.5% of them had shingles, and those people also had higher risks of both stroke and heart attack. The risk was greatest the first year after the development of shingles, decreased with time, and was highest in people under 40 years of age.
Their results by first author Min-Chul Kim and colleagues were published July 3 in the Journal of the American College of Cardiology.
Varicella zoster virus causes chicken pox — and because shingles is a reactivation of the chicken pox virus that has lain dormant in the body for years — it causes shingles, too. Shingles is very common, about a million people in the US develop it every year.
Shingles causes a painful rash that often appears as a stripe or band on one side of the body or the face. It may be accompanied by fever, headache, chills, and upset stomach, and can take up to a month to clear. Patients with shingles are treated with antiviral medications to decrease the length and severity of the infection.
The most common complication of a shingles infection is residual pain where the rash was. The infection can lead to more serious complications involving the eye, and very rarely pneumonia, hearing problems, blindness, brain inflammation, and death.
The research team used a database from the National Health Insurance Service of Korea that provided information on people who received a medical check-up between 2003 and 2013. The records of 519,880 people were used for the study, including 23,213 people who had shingles during that period and a group of people who had not had shingles but had other characteristics like age, weight, and health factors that made them suitably matched controls for the shingles group.
The scientists also noted age, sex, body mass index, obesity, smoking, drinking, exercise, economic class, hypertension, diabetes, blood cholesterol and triglycerides, heart heart and blood vessel disease, kidney disease, liver disease, rheumatoid disease, inflammatory bowel disease, cancers, transplants, HIV, and depression in the entire set of records were used for the study.
Analyses of the medical records showed that patients with shingles were more likely to be female and have common risk factors for stroke and heart attack, like old age, high blood pressure, diabetes, and high cholesterol. This group was also less likely to smoke, drank less alcohol, exercised more, and were from a higher socioeconomic group than the matched group of people who did not have shingles.
The researchers used statistical tests to exclude the influence of the multitude of other conditions they noted and found that having shingles raised the risk of heart attack by 59% and the risk of stroke by 35 percent. People below the age of 40 with shingles had the highest risk for stroke, a surprising finding given that this age group doesn't normally have an increased risk for heart attack or stroke. The risk of stroke in people under 40 who had shingles was triple the risk of those who had not had shingles.
The authors noted the association between shingles and increased risk of cardiovascular problems needs more investigation to determine the exact relationship. They suggested that the virus could cause inflammation of arteries or impact the immune system to cause the increased risks seen in the study.
For now, people who develop shingles should be aware of their increased risks and people under 40 who develop shingles should visit their doctor to check for any heart or blood vessel problems.