Q: I heard the shingles vaccine can help reduce my risk of dementia. Can you tell me more about this?
A: Yes, you heard correctly! This is based on compelling findings from a large study conducted in Wales, which suggests that certain viral infections, including shingles, may have long-term effects on brain function. Preventing these infections could delay or even help avoid cognitive decline. This is especially important given the concerning statistics around dementia in Canada. As of January 1, 2024, an estimated 733,040 Canadians are living with dementia. This number is expected to exceed 1 million by 2030. Another alarming fact is more than 350 Canadians are diagnosed with dementia every day, with the risk of developing dementia increasing with age.
Given these sobering numbers, many Canadians are turning to lifestyle changes to help reduce their risk of this debilitating condition. Popular brain-healthy habits include:
· Participating in brain games like Sudoku, crosswords, or Wordle
· Reading regularly
· Staying socially connected
· Engaging in physical activity
· Getting annual hearing checks—mid-life hearing loss can increase dementia risk by an average of 90%. It is interesting how many people that require hearing aids choose not to use them, perhaps not realizing that they are increasing their risk of dementia.
· Managing other health conditions such as high blood pressure (which raises dementia risk by 60%) and depression in later life (which increases risk by 90%)
· Maintaining a healthy weight, as obesity is also a significant risk factor
· Eating a brain-healthy diet, such as the Mediterranean or MIND diet, which emphasizes fruits (especially berries like blueberries), vegetables (especially leafy greens), whole grains, fish, seafood, and healthy fats like olive oil, while limiting alcohol, red meat, and processedfoods
Despite our best efforts, we face many daily challenges that work against our brain health. From excessive screen time to unavoidable genetic and age-related factors, it’s often difficult to make the right lifestyle changes and stick with them.
Getting back to your question about how the shingles vaccine may help prevent dementia. A recent study published in the esteemed journal Nature found that individuals who received the shingles vaccine were 20% less likely to develop dementia over the following seven years than those who were not vaccinated. Even if this protective effect is time-limited, it’s still significant, especially considering the average age of dementia onset and the lack of effective treatments currently available.
The study tracked health records of approximately 280,000 people in Wales, all aged between 71 and 88 and dementia-free at the start. Researchers capitalized on the unique rollout of the Welsh shingles vaccination program that began on September 1, 2013. Due to limited supply, only individuals who were 79 on that date were eligible for the vaccine, while those 80 and older were not. This created a rare opportunity to compare similar individuals living in the same time and place, differing by just weeks in age. The study also controlled for other possible influencing factors like education and lifestyle.
The vaccine used in that study was Zostavax, an older shingles vaccine that has since been replaced by Shingrix, which is both more effective and longer-lasting. A separate study has even suggested that Shingrix may offer greater protection against dementia than Zostavax.
You might be wondering why the shingles vaccine may help protect against dementia. One theory is that shingles, which is caused by a reactivation of the chicken pox virus (varicella zoster) which lays dormant in our nerves, among other viruses may induce inflammation in the brain. Another theory is that it boosts the immune system in a way that helps prevent cognitive decline. By preventing shingles, and thereby the inflammation in the brain, and boosting our immune system, this has been shown to protect our brain from the onset of dementia. Interestingly, the protective effects appeared even stronger in individuals with autoimmune conditions or allergies, suggesting an immune system link.
Shingrix is a two-dose vaccine given 2 to 6 months apart and does not require annual boosters. Evidence shows it is over 90% effective at preventing shingles and appears to retain most of its efficacy as it is still about 89% effective in older adults even 10 years later. The vaccine is recommended for adults aged 50 and older. Unfortunately it is not covered on our Ontario Drug Benefit (ODB) plan which every person over 65 has access to. However, it is publicly funded for Canadians aged 65 to 70, directly through your family doctor. For those of you who do not fall into this age bracket, it will cost you about $200 for one dose. Many private insurance plans include Shingrix in their list of covered medications for those outside that age range of 65 to 70.
So, should you consider asking for a Shingrix prescription? Of course, that is entirely up to you. If you have ever had shingles, or known someone who has, you may understand how painful anddebilitating it can be, with nerve pain that may continue for months or possibly years afterwards. It has been known for years how well the shingles vaccine protects us against shingles, or at the very least, reduces the severity if we do get it. Now to learn that it may also reduce our risk of dementia by 20%, that may make it more convincing for those who are sitting on the fence.
For more information on this or any other health related topic, contact your pharmacist.
