This Easter will mark one year of my working with the Neuroepidemiology Unit (NEU) at the University of Melbourne – and what a year it’s been. 2020 was a strange time to enter the workforce as an Epidemiologist, having graduated from my postgraduate degrees in Public Health at the end of the previous year. COVID has thrust infectious diseases and health research into the limelight, transforming an array of usually unfamiliar terms like ‘epidemiology,’ ‘infectious rate’ and ‘active cases’ into commonly used words. The year presented me with lots of new opportunities, balanced against so many challenges and a good deal of stress, that I will still be trying to fully comprehend it for months to come.
Over this tumultuous period, I can consider myself nothing but lucky to have been able to work with such a supportive and caring collective of people as are found in the NEU. Each of us have been fighting our own battles, but by banding together and working on a cause we share passionately, we have been able to keep ourselves that little bit more motivated and connected to the world. The passion the team brings to their research into MS is incredible – from hours of overtime spent meeting deadlines and fighting for funding, to debating, editing, and improving our work to produce the absolute best research we can.
Fuelled by this commitment to inform the best treatments and strategies for helping people with MS, the NEU is driven to better understand how the many elements of MS interconnect to affect health and wellbeing. Our latest research, which began as my master’s research project and grew to the complex paper it is now, has focussed on fatigue, and the ways it impacts on mental quality of life (QoL) in people with MS. Fatigue is one of the earliest and most common symptoms of MS, and treatments to combat fatigue are lacking, so learning about how it affects people with MS can help develop ways to minimise its impacts.
The objective of this research was to assess potential intermediary lifestyle or health factors mediating the detrimental effects of fatigue on mental quality of life in the participants from the HOLISM study. Fatigue in MS can directly lower QoL through lowered motivation and energy, and reduced ability to do everyday tasks. However, the researchers hypothesised that fatigue could also lower QoL through increasing the risk of depression, as depression is greater than 50% more likely in those with significant fatigue. Physical activity levels may provide another path, with fatigue causing lower mobility and independence, and less ability to exercise, which is linked to marked worse health outcomes in people with MS compared to those who exercise regularly.
The findings first confirmed what we already know: after taking into account important factors like disability and comorbidities, emotional QoL was more than 10% lower in those with clinically significant fatigue, and a worrisome 27% lower in those with a high depression risk. Next came the more complex part: determining exactly how much of the lost quality of life from fatigue was caused by depression and reduced physical activity. This required a more intricate approach, involving analysing models mapping out the numerous factors that might influence one another to untangle the link between fatigue and mental QoL.
Two things were revealed from this advanced analysis. Firstly, fatigue contributed significantly to reduced QoL due to its contribution to depression. This means that a large component of the QoL lost due to fatigue in MS might be improved or even prevented by managing depression, including by medications, counselling, or other mental health improvement methods. The results further showed this was true for all aspects of emotional QoL - in particular for emotional wellbeing and limitations due to emotional issues.
The second of the findings was quite surprising: physical activity seemed to have a negligible role in mediating fatigue and emotional QoL. This was despite existing research showing that fatigue, physical activity, and quality of life are strongly interconnected. One explanation is that the relationship may only be present in physical QoL, and not emotional QoL. Alternatively, measuring physical activity only through questionaries may not fully capture actual physical activity levels. This presents a very exciting direction for future research where we measure physical activity via more reliable means, such as via mobile devices or pedometers.
The finding of depression as a mediator of fatigue and quality of life is an important one for the MS community. It provides not only a way to lessen the impacts of fatigue, but it also shows that the effects of difficult to treat symptoms can be improved via unexpected ways.
To find out more about the NEU, click here.