Latest news with #coldsores
Fox News
23-05-2025
- Health
- Fox News
Cold sores may play role in Alzheimer's development, new research reveals
Cold sores may play a role in the development of Alzheimer's disease, according to a new study published in BMJ Open. Researchers examined 344,628 "case-control pairs." The pairs were matched in age, sex, geographical region and number of healthcare visits — but one had Alzheimer's disease and one did not. Of the groups studied, 1,507 people with Alzheimer's also had herpes simplex virus type 1 (HSV-1), which is the most common cause of cold sores. Only 823 people in the control group had HSV-1. Among these 2,330 people, 40% used anti-herpetic medication following their diagnosis. Those who were treated for the virus were 17% less likely to develop Alzheimer's disease than those who didn't use the treatments, the study found. The risk of developing this form of dementia is known to rise with age. However, the chance of an HSV-1 diagnosis was 80% higher in those diagnosed with Alzheimer's, according to the research. Less commonly, cold sores can be caused by herpes simplex virus type 2 (HSV-2). The analysis places "an even greater emphasis on viewing the prevention of herpes viruses as a public health priority," the researchers said in a press release. Overall, women made up 65% of the Alzheimer's cases. Their average age was 73, and they tended to have more co-existing conditions, which were all risk factors. The study also observed the potential role of other herpes viruses, some of which were associated with an elevated risk of Alzheimer's disease. The specific connection between viruses like HSV-1 and heightened dementia risk isn't clear, the researchers noted. "However, studies have shown that inflammatory alterations in the brain caused by HSV infection are pivotal in [Alzheimer's disease] development," they said in the release. Treatment with anti-viral therapy seems to lower the risk of Alzheimer's, "suggesting that HSV-1 treatment may be protective," the study says. "There's no cure for cold sores, but treatment can help manage outbreaks," according to Mayo Clinic. "Prescription antiviral medicine or creams can help sores heal more quickly. And they may make future outbreaks happen less often and be shorter and less serious." There were some limitations in the study, the researchers acknowledged. "Due to limited data history, HSV-1 infections prior to the patient's database entry were not included in the analysis, and it is possible that some overlap exists between HSV-1 and HSV-2 diagnoses," the researchers noted. "Additionally, many individuals with HSV-1 infection are asymptomatic, and others may not seek medical care during recurrences and are therefore not clinically diagnosed and recorded in the database." While an estimated two-thirds of people under 50 are infected with HSV-1, data on symptomatic infections is limited, "as manifestations can be mild or unnoticed," the researchers added. For more Health articles, visit Under-diagnosis of Alzheimer's disease could also skew the results. Fox News Digital reached out to the researchers and other doctors for comment.
Medscape
20-05-2025
- Health
- Medscape
The Strange Link Between Cold Sores and Alzheimer's Disease
This transcript has been edited for clarity. Welcome to Impact Factor , your weekly dose of commentary on a new medical study. I'm Dr F. Perry Wilson from the Yale School of Medicine. Two-thirds of you reading this will know the feeling. It starts with a numb, tingly, feeling in the lip. A day or so later, some redness, some swelling, and then, yup, a cold sore. It's a little frustrating, maybe a little embarrassing, but you wait it out for a few days and it goes away. No big deal, right? Except for the fact that multiple studies suggest that cold sores might increase your risk for Alzheimer's disease. Cold sores come from a viral infection, specifically herpes simplex virus 1 (HSV-1). There are multiple herpesviruses, which are all DNA viruses and include HSV-2 which causes the sexually transmitted infection; though, to be fair, both HSV-1 and -2 can lead to both types of infections. Varicella — the virus that causes chicken pox and shingles, Ebstein-Barr virus, CMV — are all herpesviruses. If you're human, you have almost certainly been infected by at least one. In any case, HSV-1 is one of the most common viral infections in the world. It's estimated that about two-thirds of the adult population are infected. Unlike other viruses, such as flu or coronavirus, herpesviruses are incredibly difficult to completely fight off from your body. They get around immune surveillance by hiding out in the nucleus of other cells as just an innocuous bundle of DNA. This latent phase is asymptomatic. It lies dormant until, for reasons that are still not entirely clear, the DNA bundle loosens a bit and the cellular machinery turns those instructions into the proteins that make up new virus particles and boom — outbreak. The immune system gets revved up, the outbreak is contained, and the cycle repeats. What does this all have to do with Alzheimer's disease? I was inspired to dig into this a bit because of a study appearing this week in BMJ Open , which suggests that HSV-1 infection nearly doubles the risk of Alzheimer's. Let me run through the study's findings and then we can figure out if this makes any sense at all. Researchers used the IQVIA PharMetrics Plus database to conduct the study. This is basically a large administrative claims database that covers much of the United States. It basically aggregates all the billing codes for medical care and medications from a bunch of commercial insurers; there are more than 200 million individuals represented in the file. From those, they found 344,628 individuals who were diagnosed with Alzheimer's disease. For controls, they identified another 344,628 individuals with the same age, gender, region of the country, date of entry into the database, and — to account for contact with the medical system — the number of inpatient and outpatient visits. Despite that, the groups were not exactly comparable. The individuals who would go on to develop Alzheimer's disease had a greater number of comorbidities, for example. But the kicker of the study — the headline — is this finding. People with Alzheimer's disease were twice as likely to have HSV-1 compared with the controls. After accounting for the differences between them, infection with HSV-1 increased the odds of subsequently developing Alzheimer's disease by 80%. Did you catch the problem with this graph? Take a look at the Y-axis. That's on the percentage scale. Sure, the people who went on to develop Alzheimer's disease had double the rate of HSV-1 infection, but the raw number is 0.44% vs 0.24%. Didn't I tell you at the beginning that about two-thirds of us are infected with HSV-1? That's quite a bit higher than 0.44%. What is going on here? Welcome to the world of administrative data. The problem here is that the researchers could only identify people with HSV-1 based on some provider diagnosing them with HSV-1. More than that, entering a billing code for HSV-1. Have you ever had a cold sore? Do you know whether your doctor added that to your medical history and billed insurance for it? Probably not. So we're missing an enormous number of infections here, and that calls the whole conclusion into question. Now, you might say, sure, doctors aren't diagnosing the vast majority of HSV-1 cases, but surely this is true both for people who go on to develop Alzheimer's and for those who don't, and therefore the inference is valid. Maybe. But I'd feel better if we were talking about missing something like 10% of diagnoses instead of 99% like we are here. I don't want to discount this too much, though. The paper has some other interesting findings. For instance, there was also a higher rate of HSV-2 and varicella infection among those who developed Alzheimer's disease; those are the other herpesviruses that infect nerve cells. There was no difference in rates of cytomegalovirus infection — another herpesvirus, but one that infects monocytes instead of nerve cells. But let's say we believe the link between HSV and Alzheimer's, what can we do about it? The authors hypothesized that, if HSV is causative of Alzheimer's, treatment with antivirals would reduce the risk of Alzheimer's disease. And since prescription information was present in the dataset, they could model this. Sure enough, those treated with antivirals were less likely — about 17% less likely — to develop Alzheimer's disease. This is interesting to me. In general, when you look at people who are treated for a condition, you can assume they had a more severe form of the condition (short of the treatment being done in the context of a randomized trial). Basically, people who get treated tend to be sicker than people who don't get treated, and so, in general, you see worse outcomes in the treated group — a stubborn problem in observational data called confounding by indication. Here, we see the opposite, which adds some weight to the argument. So, despite the poor capture of HSV-1 infections, the link could be real. Some other studies support this hypothesis. Alzheimer's disease is characterized by amyloid plaque deposition in the brain. Some mouse studies have shown that HSV induces the formation of amyloid plaques as an immune response and impairs the mouse's cognitive ability. This study prospectively studied 1000 Swedish older adults over time and measured antibodies to HSV: 82% of people had those antibodies which comports with what we would expect. Still, those with the antibodies had about twice the risk of developing dementia as those without. The authors of the paper in BMJ Open suggest 'antiherpetic therapies as potentially protective for AD-related dementia.' That feels like a bit of a leap to me at this point, and I will point out that this paper was funded by Gilead Sciences who have quite a few antivirals on the market and a new anti-herpetic drug that has recently completed phase 1a testing— so… grains of salt. Still, for those who suffer from cold sores, a study like this may push you a bit towards treatment, at least during an outbreak. Short-term valacyclovir is relatively safe and reduces the duration of the cold sore by about a day, which is nice. But if it reduces your risk of dementia as well, well, it might be a no-brainer.
Daily Mail
20-05-2025
- Health
- Daily Mail
Common medicine used by millions could slash the risk of Alzheimer's, study finds
Catching the virus that causes cold sores almost doubles the risk of developing Alzheimer's - but treatment slashes the odds, a study suggests. Researchers previously found the herpes simplex virus type 1 (HSV-1) can lie dormant in human cells for a lifetime before 're-awakening', leading to dementia symptoms. It has been shown to cause changes that resemble those in the brains of dementia patients, such as amyloid plaque-like formations and inflammation. Now, a large study suggests that treating HSV-1 may be a route to lessening the risk of Alzheimer's disease. Scientists, including from pharmaceutical firm Gilead Sciences and the University of Washington in Seattle, used data on 344,628 people with Alzheimer's matched with the same number of people without the disease. All were aged over 50 and the diagnosis of Alzheimer's was made between 2006 and 2021. A history of HSV-1 diagnosis was noted for 1,507 (0.44 per cent) patients with Alzheimer's, compared with 823 (0.24 per cent) of those without. Nearly two thirds (65 per cent) of those with Alzheimer's disease were women, with an average age if 73. The study found that people who had suffered the herpes virus had an 80 per cent increased risk of Alzheimer's, even when other factors were taken into account. But those with HSV-1 who used anti-virals to treat the virus were 17 per cent less likely to develop Alzheimer's compared with those who did not the medicines. Among the 2,330 people with a history of HSV-1 infection, 931 (40 per cent) used anti-virals after their diagnosis. The authors, writing in the journal BMJ Open, concluded: 'Findings from this large…study implicate HSV-1 in the development of Alzheimer's disease and highlight anti-herpetic therapies as potentially protective for Alzheimer's and related dementia.' In the UK, the drug aciclovir is one of those available for treating cold sores, chickenpox, shingles and other herpes virus infections. Data from the Open Prescribing website indicates doctors issue around 90,000 prescriptions for the drug in England each month. The researchers also looked at the potential role of other herpes viruses, including HSV-2, varicella zoster virus (which causes chickenpox), and cytomegalovirus. Both HSV-2 and varicella zoster virus infections were also associated with a heightened risk of Alzheimer's disease. Exactly how HSV-1 and other viruses might heighten the risk of dementia is not clear, point out the researchers. 'However, studies have shown that inflammatory alterations in the brain caused by HSV infection are pivotal in (Alzheimer's disease) development,' they added. HSV-1 DNA is also found in the plaques characteristic of Alzheimer's disease, and people carrying the most common genetic risk factor for the disease are more susceptible to HSV infections, they said. Professor Tara Spires-Jones, from the University of Edinburgh, said: 'This is a well-conducted study adding to strong data in the field linking HSV-1 and other viral infections to increased risk of developing Alzheimer's disease, but it is important to note that HSV-1 infection, which is extremely common in the population, is by no means a guarantee that someone will develop Alzheimer's. 'Why viral infections may increase risk of dementia is not fully understood, but the most likely explanation is that infections increase inflammation in the body and contribute to age-related brain inflammation. 'More research is needed to understand the best way to protect our brains from Alzheimer's disease as we age, including a better understanding of links between viral infection and Alzheimer's risk.' However, Dr David Vickers, from the University of Calgary in Canada, said the research 'exaggerates the role of HSV-1, failing to appreciate its absence in 99.56 per cent of Alzheimer's disease cases'. He added: 'The observed 17% hazard reduction with anti-herpetic drugs translates to a mere nine-month delay in Alzheimer's disease onset.' Dr Richard Oakley, director of research and innovation at the Alzheimer's Society, said: 'Results from this observational study suggested that people with recorded cold sore infections were more likely to develop Alzheimer's disease, and interestingly those prescribed antiviral drugs had a slightly lower risk. 'But this doesn't prove that cold sores cause Alzheimer's disease, or that anti-virals prevent it. 'The data came from insurance records, often based on self-reported symptoms which may miss or misclassify infections, and didn't track how often people had cold sores or how consistently they took medication. 'Much more research is needed to explore exactly how viruses might be involved and before we can draw firm conclusions.' Dr Sheona Scales, director of research at Alzheimer's Research UK, welcomed the study but said more research was needed. 'We know there are 14 established risk factors for dementia, and there's not enough evidence to include infections in this list. 'This study doesn't tell us if infections are causing the risk, it only shows an association. Further research is needed to understand what the underlying biology around this is.'
The Independent
20-05-2025
- Health
- The Independent
Treating cold sores with anti-virals ‘may slash risk of developing Alzheimer's'
Treating cold sores with anti-viral medicines could help slash the risk of Alzheimer's disease, research suggests. Previous studies have found that the herpes simplex virus type 1 (HSV-1) can lie dormant in human cells for a lifetime before 're-awakening', leading to dementia symptoms. Experts have discovered that HSV-1 causes changes that resemble those in the brains of dementia patients, such as amyloid plaque-like formations and inflammation. Now, a large US study suggests that treating HSV-1 may be a route to lessening the risk of Alzheimer's disease. Researchers, including from pharmaceutical firm Gilead Sciences and the University of Washington in Seattle, used data on 344,628 people with Alzheimer's matched with the same number of people without the disease. All were aged over 50 and the diagnosis of Alzheimer's was made between 2006 and 2021. A history of HSV-1 diagnosis was noted for 1,507 (0.44%) patients with Alzheimer's, compared with 823 (0.24%) of those without. Nearly two thirds (65%) of those with Alzheimer's disease were women, with an average age if 73. The study found that people who had suffered the herpes virus had an 80% increased risk of Alzheimer's, even when other factors were taken into account. But those with HSV-1 who used anti-virals to treat the virus were 17% less likely to develop Alzheimer's compared with those who did not the medicines. Among the 2,330 people with a history of HSV-1 infection, 931 (40%) used anti-virals after their diagnosis. The authors, writing in the journal BMJ Open, concluded: 'Findings from this large…study implicate HSV-1 in the development of Alzheimer's disease and highlight anti-herpetic therapies as potentially protective for Alzheimer's and related dementia.' In the UK, the drug aciclovir is one of those available for treating cold sores, chickenpox, shingles and other herpes virus infections. The researchers also looked at the potential role of other herpes viruses, including HSV-2, varicella zoster virus (which causes chickenpox), and cytomegalovirus. Both HSV-2 and varicella zoster virus infections were also associated with a heightened risk of Alzheimer's disease. Exactly how HSV-1 and other viruses might heighten the risk of dementia is not clear, point out the researchers. 'However, studies have shown that inflammatory alterations in the brain caused by HSV infection are pivotal in (Alzheimer's disease) development,' they added. HSV-1 DNA is also found in the plaques characteristic of Alzheimer's disease, and people carrying the most common genetic risk factor for the disease are more susceptible to HSV infections, they said. Professor Tara Spires-Jones, from the University of Edinburgh, said: 'This is a well-conducted study adding to strong data in the field linking HSV-1 and other viral infections to increased risk of developing Alzheimer's disease, but it is important to note that HSV-1 infection, which is extremely common in the population, is by no means a guarantee that someone will develop Alzheimer's. 'Why viral infections may increase risk of dementia is not fully understood, but the most likely explanation is that infections increase inflammation in the body and contribute to age-related brain inflammation. 'More research is needed to understand the best way to protect our brains from Alzheimer's disease as we age, including a better understanding of links between viral infection and Alzheimer's risk.' Dr David Vickers, from the University of Calgary in Canada, said the 'research exaggerates the role of HSV-1, failing to appreciate its absence in 99.56% of Alzheimer's disease cases'. He added: 'The observed 17% hazard reduction with anti-herpetic drugs translates to a mere nine-month delay in Alzheimer's disease onset.' Dr Richard Oakley, director of research and innovation at the Alzheimer's Society, said: 'Results from this observational study suggested that people with recorded cold sore infections were more likely to develop Alzheimer's disease, and interestingly those prescribed antiviral drugs had a slightly lower risk. 'But this doesn't prove that cold sores cause Alzheimer's disease, or that anti-virals prevent it. 'The data came from insurance records, often based on self-reported symptoms which may miss or misclassify infections, and didn't track how often people had cold sores or how consistently they took medication. 'Much more research is needed to explore exactly how viruses might be involved and before we can draw firm conclusions.' Dr Sheona Scales, director of research at Alzheimer's Research UK, welcomed the study but said more research was needed. 'We know there are 14 established risk factors for dementia, and there's not enough evidence to include infections in this list. 'This study doesn't tell us if infections are causing the risk, it only shows an association. Further research is needed to understand what the underlying biology around this is.'
Telegraph
20-05-2025
- Health
- Telegraph
Cold sore treatment could cut risk of Alzheimer's
Treating cold sores with anti-viral medicines could reduce the risk of Alzheimer's disease, new research has suggested. The virus responsible for cold sores, the herpes simplex virus type 1 (HSV-1), can lie dormant in human cells for a lifetime before 're-awakening' and causing dementia symptoms, previous studies have found. It can cause changes to the brain that resemble those of dementia patients, including amyloid plaque-like formulations and inflammation. However, a new study of around 700,000 adults aged over 50 has found that treating these cold sores with anti-viral medication could reduce the chance of the disease developing. Researchers, including some from pharmaceutical firm Gilead Sciences and the University of Washington in Seattle, used data on 344,628 people diagnosed with Alzheimer's between 2006 and 2021 and compared them to the same number of people without the disease. A history of HSV-1 diagnosis was noted for 1,507 (0.44 per cent) patients with Alzheimer's, compared with 823 (0.24 per cent) of those without. Nearly two thirds of those with Alzheimer's disease were women, with an average age of 73. A greater risk of Alzheimer's The study found that people who had contracted the herpes virus had an 80 per cent greater risk of Alzheimer's, even when other factors were taken into account. But those with HSV-1 who used anti-viral medication to treat the virus were 17 per cent less likely to develop Alzheimer's, compared with those who did not use these medicines. Among the 2,330 people with a history of HSV-1 infection, 931 used anti-virals after their diagnosis. The authors, writing in the journal BMJ Open, concluded that the findings 'implicate HSV-1 in the development of Alzheimer's disease and highlight anti-herpetic therapies as potentially protective for Alzheimer's and related dementia'. In the UK, the drug aciclovir is one of those available for treating cold sores, chickenpox, shingles and other herpes virus infections. The researchers also looked at the potential role of other herpes viruses, including HSV-2, varicella zoster virus (which causes chickenpox), and cytomegalovirus. Both HSV-2 and varicella zoster virus infections were also associated with a heightened risk of Alzheimer's disease. Exactly how HSV-1 and other viruses might heighten the risk of dementia is not clear, but they suggested that 'studies have shown that inflammatory alterations in the brain caused by HSV infection are pivotal in [Alzheimer's disease] development'. HSV-1 DNA is also found in the plaques characteristic of Alzheimer's disease, and people carrying the most common genetic risk factor for the disease are more susceptible to HSV infections, they added.
