Cold sores may DOUBLE the risk of developing Alzheimer's disease

You might think cold sores are unsightly. But they could also increase the risk of Alzheimer's, a new study suggests.

Swedish researchers found an infection of the herpes simplex virus 1 - which causes cold sores - doubles the risk of developing Alzheimer's disease.

The body carries the virus forever after the first infection, and it can reactivate now and then, causing the crusty blisters known as cold sores. 

Crusty: An infection of the herpes virus- which causes cold sores in as many as nine out of ten Britons at some point in their lives - doubles the risk of developing Alzheimer's, according to a study

While up to 90 per cent of adults have herpes simplex virus 1 lurking in their systems, only around a quarter of them will experience frequent outbreaks.

The researchers say the virus could increase the risk of Alzheimer's because elderly people have weakened immune systems, which creates opportunities for the virus to spread to the brain.

In the brain, the virus can start the process which results in Alzheimer's disease.

Plaques are formed in the brain which result in the death of brain cells and the breakdown of the connections between them.

This causes memory loss and the decline in the ability to think, which are the characteristic symptoms of Alzheimer's. 

 

Previous research suggests that people who do not get Alzheimer’s produce less amyloid - the substance which forms brain plaques - or are better at clearing it.

Professor Hugo Lövheim, from Umea University in Sweden, said the study findings could be used to develop treatment for the disease.

He said: 'Our results clearly show that there is a link between infections of herpes simplex virus and the risk of developing Alzheimer's disease.

'This also means that we have new opportunities to develop treatment forms to stop the disease.'

He added: 'Something which makes this hypothesis very interesting is that now herpes infection can, in principle, be treated with antiviral agents.

Experts said the cold sore virus could increase the risk of Alzheimer's as elderly people have weakened immune systems which allow the virus to spread to the brain more easily, where it can start the process of plaques forming in the brain which kill brain cells

'Within a few years we hope to be able to start treating patients to prevent the development of Alzheimer's disease.'

Professor Lövheim and his team carried out two studies to prove the link between an infection with the herpes virus and Alzheimer's.

In the first study, 3,432 participants were followed for 11.3 years on average.

They found that a reactivated herpes infection doubled the risk of developing Alzheimer's disease.

In the second study, samples donated to Umeå University's Medical Biobank were analysed from 360 people with Alzheimer's disease taken on average 9.6 years before they were diagnosed.

The same number of samples from people who had not developed dementia were also analysed.

Researchers found a doubled risk of developing Alzheimer's disease if the person was a carrier of the herpes virus.

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