Multiple sclerosis (MS) is a disabling disease that affects the brain and spinal cord. Up to 65% of people living with MS will experience changes in how their brain processes information such as difficulties in memory recall, problem solving and processing speed (speed of thinking). As healthcare and MS treatments improve, the number of older people living with MS continues to grow. There is very little research on how memory and speed of thinking changes as people living with MS grow older.
Dr Daniel Merlo’s research project aims to use digital tests that can be completed on a tablet or smartphone to measure changes in areas of thinking, such as memory, in people living with MS over the age of 50. Dr Merlo and his research team will look at the differences in thinking between people diagnosed with MS later in life (over the age of 50), compared to those diagnosed at a younger age. They also aim to identify changes in clinical or brain imaging features that predict if memory or speed-of-thinking will decline as people living with MS get older.
Increasing the knowledge on how thinking changes as people living with MS age will provide more information for them and their doctors to be able to make informed shared care decisions.
Defining reliable thresholds for cognitive change (changes in memory, attention and speed of thinking) in people living with MS – particularly those over 50 – will help clinicians decide whether the changes are clinically meaningful and need further investigation.
To identify reliable thresholds of change, Dr Merlo and his team have begun examining changes on the MSReactor digital tests. They measured memory, attention and reaction time over 12 and 18 months in people with MS. The team compared these changes in people aged 50 and above to changes in those who are under 50 years of age. The team has developed preliminary thresholds for these changes and is continuing to refine them.
So far, the team has found that more people with MS who are aged 50 or above will have changes in MSReactor scores that exceed the preliminary identified thresholds compared to people with MS who are under 50 years of age.
It is important to know if the changes in MSReactor test performances are due to a person’s age, their MS, or both. To answer this question, researchers compared MSReactor results between three groups: people with MS aged 50 and over, people with MS under 50, and people without MS.
Initial results showed that people with MS aged 50 and over performed worse on MSReactor tasks than those with MS who were under 50. Their performance was also substantially worse than a comparison group of more than 1,000 people without MS who were also aged 50 and above. This suggests that changes in MSReactor task performance is due to ageing with MS rather than natural ageing.
MSReactor data is now included in the MSBase registry dataset. This dataset is available to clinicians at each outpatient appointment and includes the participant’s clinical history. This means that changes in cognitive function may be used in shared decision-making with clinicians and people with MS
Dr Merlo is preparing a scientific publication based on this study. Since the start of this study, Dr Merlo and his team also established collaborations with the Centre of Eye Research Australia that will focus on some exciting and innovative aspects of ageing in MS.
Updated 31 March 2026Â
MSWA
$225,000
2025
3 years
Current project
