Why does shingles increase the risk of stroke?

Herpes zoster is a common infectious skin disease that is more common in adults and occurs more frequently in spring and autumn. For many years, herpes zoster was mainly known as a skin disease, but recent studies have found that having herpes zoster may increase the risk of stroke in the future [1].

Herpes zoster is an acute infectious skin disease caused by the varicella-zoster virus. This virus can cause chickenpox in people who are not immune to it. After people recover from chickenpox, the virus can remain dormant in the neurons of the dorsal root ganglia of the spinal nerves for a long time due to its neurotropic properties. When the resistance is low or when people are tired, infected, or have a cold, the virus can grow and multiply again and move along the nerve fibers to the skin, causing strong inflammation of the invaded nerves and skin. Varicella-zoster virus infection is characterized by a red rash that can cause pain and burning. It usually manifests as striped blisters on one side of the body, mainly on the trunk, neck, or face. The infection rate of varicella-zoster virus is very high, and it can infect more than 95% of the world's population. Herpes zoster caused by the reactivation of varicella-zoster virus has always been considered a benign disease. After timely treatment, the rash can subside in a few weeks, and complications rarely occur in a short period of time. However, recent studies suggest that shingles may increase the risk of stroke in the future, with people aged 18 to 40 years with shingles more likely to suffer from stroke, heart attack, or transient ischemic attack than people without shingles [1].

The varicella-zoster virus can infect the cerebral arteries and cause inflammation, leading to pathological vascular remodeling, intimal thickening, vascular occlusion and ischemia, which can easily cause ischemic and hemorrhagic strokes [2]. After the subsidence of shingles, it is usually accompanied by persistent pain (postherpetic neuralgia), and some patients may also experience cranial neuropathy, meningitis, encephalitis, transient cerebral ischemia, etc. After adjusting for stroke risk factors such as obesity, smoking and high cholesterol, researchers found that people under 40 years old who had shingles were 74% more likely to have a stroke. A recent study found that the shingles vaccine can reduce the risk of ischemic and hemorrhagic strokes, and this protective effect is strongest in people aged 60 to 69. Overall, vaccination with the shingles vaccine can reduce the risk of stroke by about 16%, including reducing the risk of ischemic stroke by about 18% and the risk of hemorrhagic stroke by about 12% [3].

Shingles is very common in adults. If you have symptoms of shingles, you should seek medical attention in time, receive professional treatment, and have regular checkups to be alert to cardiovascular and cerebrovascular complications caused by shingles. Currently, the shingles vaccine for the varicella-zoster virus is on the market. Researchers encourage people aged 50 and over to get the shingles vaccine under the advice of a doctor, which can reduce the risk of shingles and stroke at the same time.

1.Breuer J, Pacou M, Gautier A, Brown MM: Herpes zoster as a risk factor for stroke and TIA: a retrospective cohort study in the UK. Neurology 2014, 83(2):e27-e33.

2.Nagel MA, Gilden D: The relationship between herpes zoster and stroke. Current neurology and neuroscience reports 2015, 15(4):16.

3.Klaric JS, Beltran TA, McClenathan BM: An association between herpes zoster vaccination and stroke reduction among elderly individuals. Military medicine 2019, 184(Supplement_1):126-132.