Shingles, a reactivated form of the chickenpox virus, is a painful rash that afflicts many people decades after the initial chickenpox infection. Now, we have data that shingles increase heart attacks (myocardial infarction) and strokes. This is more evidence that we need to end chickenpox with the chickenpox vaccine and reduce the risk of shingles in those who have had chickenpox with the shingles vaccine.
Let’s take a look at shingles and this new study.
What is shingles?
One of the consequences of contracting chickenpox, a virus called Varicella zoster, is that it is not destroyed by the body’s immune system in most individuals. Once the symptoms of chickenpox disappear, the virus hides itself in various nerve cells. The virus then remains hidden from the body’s immune system.
As a result of unknown factors, although stress or other infections may be involved, the zoster virus reactivates and moves along the nerve bundles, then causes a second infection, called shingles (see Note 1), which has much more serious consequences to the patient. Even though the body had generated an immune response to the original zoster infection, after several decades, the immune response has either weakened or disappeared.
The reactivated virus moves along the nerves to the skin. At that point, it causes significant pain followed by a chickenpox-like rash. Usually, shingles happen when the patient is older than 50, although it can happen at any time, occasionally even in young adults.
Shingles is an entirely unpredictable disease. It really appears at random points in time in response to unknown variables.
Once shingles appear, it can be incredibly painful, depending on the location of the outbreak. It can cause blindness, disfigurement of the area infected, permanent pain, and other conditions. One of the more serious and common complications of shingles is postherpetic neuralgia.
Antivirals are the primary treatment for shingles. However, antiviral effectiveness is limited to 24-72 hours after initial diagnosis. This might not allow most individuals to get diagnosed by their doctor. The initial symptoms may even appear like acne or some other skin condition, which many people might ignore.
There are two ways to prevent shingles.
First, prevent a chickenpox infection in the first place. The chickenpox vaccine is part of the CDC-recommended vaccine schedule, and as a result, the rate of chickenpox infections in the USA, and many other countries, has dropped significantly. Chickenpox incidence has dropped by 87% from the 4 million cases a year prior to vaccine availability (1994-95) until today.
Furthermore, chickenpox mortality has dropped by 99% from the pre-vaccine era.
Lucky for those of us who have had chickenpox, we have a shingles vaccine, called Shingrix, which is extremely safe and very effective in preventing an occurrence of shingles. It’s recommended for people 50 and older, but if you have had shingles at a younger age, I’d get the vaccine whatever your age to prevent a reoccurrence of shingles. In case you’re wondering, getting shingles will not make you immune to a second or third bout of the disease in the future.
So let’s be clear about a couple of things. First, you are only at risk for shingles if you had contracted chickenpox in the past. Second, children vaccinated against chickenpox probably will never contract shingles. Is this clear? The chickenpox vaccine prevents chickenpox AND shingles.
Shingles increase heart attacks and strokes
In a paper published in July 2017 in the Journal of the American College of Cardiology, researchers examined the health records of 519,880 patients between 2003 and 2013. Amongst that group, 23,233 individuals suffered a bout of shingles. The authors then compared that group with a similar-sized group who had never contracted shingles
The researchers accounted for confounding risk factors such as age, blood pressure, diabetes, cholesterol level, tobacco smoking, alcohol intake, exercise and socioeconomic class.
Here are there key results:
- Shingles raised the risk of stroke alone by 35%.
- Shingles raised the risk of heart attack alone by 59%.
- Shingles raised the risk of all cardiovascular events, including heart attack and stroke, by 41%.
- Individuals under the age of 40 who had contracted shingles were at the greatest risk of stroke. You should consider the shingles vaccine if you’re that age.
The authors concluded:
In conclusion, we have demonstrated that HZ (herpes zoster) significantly increases the risk of stroke and MI (myocardial infarction) even after rigorously adjusting possible confounding factors in a large population cohort. The risks were especially high in the relatively young who have fewer risk factors for atherosclerosis. Furthermore, there was a substantial temporal link between HZ and the occurrence of stroke and MI.
Shingles increase heart attacks – the summary
This large sized study gives us robust evidence that shingles can substantially increase the risk of heart attacks and strokes. The disease has also been linked to an increased risk of dementia and Alzheimer’s disease. It’s a good thing that we have the technology to prevent shingles.
First, we can prevent the original chickenpox infection with the chickenpox vaccine.
Second, if you contracted chickenpox, we can prevent shingles with the shingles vaccine.
Here are your choices – prevent the virus from attacking you in either form. Or let shingles increase heart attacks and strokes later on. The decision is easy – vaccines.
- Shingles is often called herpes zoster despite being the same exact virus. Since they appeared as two different diseases, they were given two different names. Despite the confusing names, the Varicella zoster virus is the cause for both chickenpox and shingles.
- Centers for Disease Control and Prevention (CDC). Decline in annual incidence of varicella–selected states, 1990-2001. MMWR Morb Mortal Wkly Rep. 2003 Sep 19;52(37):884-5. PMID: 13679791.
- Kim MC, Yun SC, Lee HB, Lee PH, Lee SW, Choi SH, Kim YS, Woo JH, Kim SH, Kwon SU. Herpes Zoster Increases the Risk of Stroke and Myocardial Infarction. J Am Coll Cardiol. 2017 Jul 11;70(2):295-296. doi: 10.1016/j.jacc.2017.05.015. PubMed PMID: 28683973.