Dalhousie University


Research / Projects
Mathematical Models to Help Us Understand Change

Generally, your cognition declines with age - faster in some people than others and in some individuals, cognition is even seen to improve.  The variability is because no two people are alike.

Trying to find the patterns in this inconsistency is of great interest to researchers at the Geriatric Medicine Research Unit.

Our work has focused on a something called a ‘multi-state transition model’.  This model(s) allow us to study patterns of change in any condition or phenomenon and we use them to study things such as stages of change in the cognition of people with Alzheimer’s disease.

These models can capture change in all directions: stability, decline, and even improvement and they allow all the factors that may be influencing this change to be studied as well.  We are especially interested in patterns of improvement in cognition and which factors may influence this.

An example of improvement in cognition may be seen with exercise. It is generally accepted that exercise is good for people at all stages of their life.  Using a multi-state transition model, we examined data from over 8,000 Canadians and found that in people with Alzheimer’s disease, exercise was an important factor in cognitive improvement. And for those who did not have Alzheimer’s disease, exercise was an important preventative factor in maintaining their cognitive abilities.

Before we began our work on exercise and cognition, there was a paradox in the relationship between these two things: exercise helps you to live longer however, the longer you live the greater the chance you will develop Alzheimer’s disease.
Our research has shown that people who exercise regularly do live longer and are less likely to develop Alzheimer’s disease.

Our investigation is ongoing with exploration being carried on topics such as frailty in elderly people.



Dalhousie University Faculty of Medicine