As we face down yet another season of sniffles, staying healthy may be harder simply because we’re another year older.
It’s estimated that between 70 and 85 per cent of seasonal flu-related deaths have occurred in people 65 years and older. Not to mention, the flu can increase the risk for pneumonia, which more people over the age of 65 die from each year than car accidents.
We recently spoke with Dawn Bowdish, the Canada Research Chair on Aging and Immunity, who has spend the last 10 years heading up a lab at McMaster University’s Institute for Research on Aging. She focuses on how changes to our immunity as we age can leave us more susceptible to pneumonia.
TARA LOSINSKI: Why does our immune system dampen with age?
DAWN BOWDISH: My lab’s work says that as we get older, the amount of inflammation in our blood creeps up, and that impairs a lot of our immune cells. There’s other data saying that some of the viruses we’re exposed to over our life course changes or remodels our immune system. So we don’t have a clear answer about why it happens but we know it does happen.
Many groups, including my own, are very interested in finding new treatments or therapies that work within the context of the aging immune system. For example, my lab uses aged mice instead of young mice. We find that some of the things that work in young mice don’t work in old mice – and vice versa. You have to remember there’s a lot going on – our physiology changes, our immune system changes, our metabolism changes – and all these things impact our ability to fight infections.
TL: So is that what makes us more susceptible to pneumonia?
DB: Our preconception is we just don’t respond [as well] to the bacteria that causes pneumonia. But as we age, we have more and more inflammation in our blood and in our tissues and in our lungs. That seems to impair the way our immune cells are made. And so instead of being less responsive when they see the bacteria, we make even more inflammation, and that can cause people to have a lot of fluid in their lungs. So that’s what kills us when we have pneumonia, the fluid in our lungs.
This increase in inflammation as we get older is also probably one of the reasons that other inflammatory conditions get worse after pneumonia because it bumps up all this inflammation.
TL: What conditions can pneumonia exacerbate?
DB: There’s a strong link to having cardiovascular events after having pneumonia: heart attacks and heart disease.
And, I want to make this clear, it’s not a pneumonia that you can deal with outside of the hospital but if you have pneumonia that requires you to go to the hospital. the risk of dementia is very much higher in the next few years. In fact, hospitalization with pneumonia is more closely associated with dementia than any other hospitalization.
And sometimes older adults who end up in the hospital have what we call “catastrophic disability.” They came into the hospital reasonably healthy and active but, by the time they leave, they’re less able to do the activities of daily living. Because pneumonia is such an intense event that they start losing muscle mass – it makes them so sick, and it’s really hard to recover from that.
TL: How do we get pneumonia? Does the flu turn into pneumonia?
DB: The most common kinds for older adults is what we call post-influenza pneumonia. It may start off as being something you can deal with, and then the pneumonia bacteria just take advantage really. They see that you’re compromised and take advantage. So this is why we say get your flu shot and pneumonia vaccine because often times if you survive the influenza, you’re still very vulnerable – and that’s often what kills people.
There’s also what we call community-acquired pneumonia, which is not necessary associated with influenza but usually a bacterial infection in the lungs.
TL: So avoid the flu! And when do we get the adult pneumonia vaccine?
DB: First, it’s important to get the flu shot every year because it changes every year. The pneumonia vaccine is slightly different. It’s imperfect in that it doesn’t capture every single bacteria that causes pneumonia but it does work against the one that is most common in adults. It comes in two different flavours. The recommendations right now is that you have one pneumococcal conjugate vaccine (PCV) first and then, about six months later, you have the pneumococcal polysaccharide vaccine (PPV). So that’s recommended for everyone over 65 or for those who have other conditions that would make them more venerable.
I’ll also say one of the best things to do is make sure your kids are vaccinated as well. There’s this thing called the “Christmas spike” where when grandparents and grandkids get together over the holidays, there’s a spike. And it’s been seen that some reduction in older adults is because we’re getting kids vaccinated.
TL: What do you say to skepticism about vaccines?
DB: People are skeptical because they think they’re linked to harmful side effects or because they think they don’t need them. Older adults generally aren’t as worried about them being harmful as they may remember a time when vaccine-preventable diseases like polio or whooping cough ruined lives. The benefits of vaccination have always outweighed the side effects but, for those think vaccination might be harmful, I’d suggest talking to your doctor or looking at sources like the Public Health Agency of Canada or the National Advisory Committee on Immunization.