St. Joe’s scientists are among the members of an international research team working to understand how infections accelerate cognitive decline and dementia, particularly in older adults.
The team, which is co-led by Dr. Dawn Bowdish, has been awarded a 3-year Brain Aging grant totalling $750,000 from the Canadian Institutes of Health Research (CIHR).
Dr. Bowdish is a professor at McMaster University and the executive director of the Firestone Institute for Respiratory Health at St. Joe’s. She is co-leading the team with Dr. Chris Verschoor of Health Sciences North Research Institute in Sudbury.
The international team includes several Hamilton scientists, including Dr. Andrew Costa, research director of St. Joe’s Centre for Integrated Care.
The funding was announced as part of an $8.7 million research investment by the Government of Canada, aimed at funding research projects related to brain health and age-related cognitive impairment.
Studies have shown that a serious respiratory infection such as influenza, pneumonia, or COVID-19 can accelerate cognitive decline and dementia in mid- to late-life adults, even in healthy individuals with no pre-existing conditions.
Researchers believe that inflammation caused by an infection contributes to cognitive decline. Their hypothesis follows observations showing those with higher inflammation levels develop cognitive decline and dementia faster than those with low inflammation levels.
In healthy individuals, the brain’s immune cells – called microglia – clean up the wear and tear in the brain by scavenging for plaques, damaged or unnecessary neurons and synapses, and infections. Inflammation, particularly during the recovery period of an infection, may impair microglia from doing their job and contribute to lasting cognitive decline.
There have also been several studies indicating the important differences between male and female pneumonia patients with regards to in-hospital and post-discharge health outcomes. Though sex differences in post-pneumonia cognitive impairment are not entirely understood, the team believes that women will be at a greater risk compared to men, given that they are more likely to develop dementia.
Researchers will work to determine which parts of learning, memory, and microglia function are impaired by inflammation, as well as how infection harms learning and memory. The team will also use epidemiological data to understand correlations involving dementia patients who previously had a pneumonia infection compared to those who did not have pneumonia.
To achieve this, the research team is comprised of experts in a variety of fields, including health systems research, longitudinal studies of aging, murine models of pneumonia and age-associated inflammation, murine behaviour, and brain imaging.
The long-term goal of the project is to develop therapeutics to prevent post-pneumonia cognitive decline.
“Until there are therapeutic options, keeping up-to-date on vaccinations is the only risk reduction strategy available,” says Dr. Bowdish.
This CIHR funding comes from the Institute of Aging’s Brain Health and Cognitive Impairment in Aging Research Initiative (BHCIA).
“CIHR’s Institute of Aging is proud to support research in the field of aging and to provide a solid foundation for the future of the field by training and mentoring the next generation of dementia researchers in Canada,” said Dr. Jane Rylett, Scientific Director, CIHR Institute of Aging.