A research team at Asan Medical Center has confirmed that if patients suffering from shingles leave their symptoms untreated, it can increase the risk of dementia.
|An Asan Medical Center research team has found that untreated shingles symptoms can increase the risk of dementia. From left are Professors Kim Sung-han, Bae Sung-man, Yoon Sung-chul, and Kim Seong-yoon. (AMC)|
The team, led by Professors Kim Sung-han, Bae Sung-man, Yoon Sung-chul and Kim Seong-yoon at the hospital, came to such a conclusion after analyzing the incidence of dementia in shingles patients who either received treatment or did not receive treatment, by using the National Health Insurance Service data for 2002 to 2013.
As a result, the rate of dementia in the group that did not receive shingles treatment was 1.3 times higher than the treatment group. In contrast, patients who received treatment with antiviral drugs reduced their dementia risk by about a quarter.
"Shingles occurs when the chickenpox virus, which is infected as a child, lurks in the nerve cells and then spreads around the nerve when the body's immunity decreases," the hospital said. "If patients show blistering and pain symptoms, they should receive treatment with an antiviral agent within 72 hours."
If treatment is delayed, there is a high possibility of secondary infection or chronic neuralgia even if the blisters and rashes disappear, the hospital added.
The researchers estimated that the shingles virus's neuro-invasive nature could cause local or systemic inflammation and immune system abnormalities, which affects the development of dementia.
The team also suggested that the shingles virus uses an insulin-degrading enzyme (IDE) as a receptor when it enters the cells may be another reason for the increased risk of dementia.
"The enzyme breaks down the beta-amyloid protein, which is a major cause of Alzheimer's dementia," the team said. "If the shingles virus blocks the enzyme activity, beta-amyloid protein deposition may progress to the cerebrum."
The researchers speculated that the beta-amyloid protein produced by neurons to combat shingles virus infection might paradoxically contribute to the development of dementia.
"This study is significant because it uncovered the epidemiological linkage between common shingles and dementia by using big data," Professor Kim Sung-han said. "However, the causal relationship between the two diseases has not been confirmed definitively, so further studies are needed."
Professor Kim also urged patients suffering from shingles to receive antiviral treatment.
"Vaccination can reduce the chance of getting shingles by 60 percent," he said. "People over 50 who are prone to shingles due to reduced immunity should receive the vaccine in advance and increase their immunity through adequate nutrition, sleep, and stress management."
European Archives of Psychiatry and Clinical Neuroscience published the results of the study.