Predicting post-stroke recovery - with Dr Kate Hayward

Dr Kate Hayward returned from Canada to The Florey Institute of Neuroscience and Mental Health in 2018 to work in the Stroke Theme. She is an NHMRC Early Career Research Fellow in the AVERT Early Rehabilitation Research Group. Kate has a triple thread of skills: physiotherapist, rehabilitation scientist and clinical neuroscientist. We spoke to her about her research at the Florey.

Tell us about your research.

My research looks into how we can improve recovery after stroke, focusing on people with severe loss of movement in their arm and hand. Arm and hand use is integral to most of our daily tasks, whether it’s gesturing during a speech, embracing a loved one in a hug, or picking up your morning cup of coffee. Up to 75% of stroke survivors have reduced use of their arm and hand early after stroke, and recovery is really variable - it’s almost a fifty-fifty chance as to whether someone with very little movement will recover. We need to understand what determines who recovers, who doesn’t recover, and why.

So how can you predict arm and hand recovery in stroke?

Two methods have received the most attention to date: transcranial magnetic stimulation (TMS) which tells us about the function of the motor pathways, and diffusion tensor imaging, a type of MRI, which tells us about the structure of the motor pathways.

TMS tests the connection between the brain and the arm and hand. A coil is held over the scalp and induces an electromagnetic current, which causes a cascade of signals to pass between receptors in the brain. The output is measured via muscle activity in the arm or hand and is called a motor evoked potential. If these potentials are present early after stroke, this can mean the person will have a better recovery because it tells us that the brain can send a signal down to the arm or hand to move.

TMS is only sensitive up to a certain level, so we also use neuroimaging to understand recovery profiles. In situations where there is severe loss of movement and we cannot see a motor evoked potential, we can use diffusion tensor imaging to visualise the corticospinal tract and see if we can reconstruct the motor pathways.

How are you using TMS and diffusion tensor imaging in your research?

We want to look in more detail at people with severe arm and hand impairment, because to date they have often been excluded from studies or studied in very small samples. We need large cohorts of patients to attempt to predict recovery more accurately. There was work around this in the Stroke Recovery and Rehabilitation Roundtable recommendations published in International Journal of Stroke in 2017.

We are currently running a longitudinal study ‘Characterising Arm Recovery in People with Severe Stroke (CARPSS)’ in Canada that collects clinical outcomes, as well as MEP and neuroimaging data at four timepoints over the first year after stroke. We are also using MEP outcomes in a clinical trial that is currently running in Melbourne Australia, ‘Very Early Start to Personalised Upper limb Rehabilitation (VESPUR)’. Here we stratify patients based on their MEP outcome to ensure that each randomisation group has similar numbers of people with and without a MEP present.  

How will your research benefit stroke survivors in the long term?

We want to test if using a more specific approach to select patients for treatments can lead to better outcomes. By identifying subgroups of stroke survivors who respond best to a given intervention, we can target our treatments rather than adopting a one-size-fits all approach. Put simply, we want to be able to apply the right treatment to the right patient post stroke.  

We also want people to achieve more than the spontaneous recovery that occurs naturally post-stroke. If we help people get recovery of arm and hand function beyond spontaneous, we could accelerate their pathway to getting back to what matters most to them.

Dr Kate Hayward at the Bayer Foundation Alumni Day in Berlin, 2018

What’s your favourite thing about working at the Florey?

I really love the collaborative nature and united vision of people here. Everyone wants stroke survivors to have better outcomes, and we all work together to achieve that goal. I think it’s possible because we are all on the same floor in the same building. You walk past people, you chat to them, and discussion fosters new ideas. We’re not working in isolated labs or silos within stroke, we are all working together, which I think is great.

What inspired you to pursue stroke research?

My Honours supervisor was an amazing mentor. She had a contagious energy and passion for the questions that she was asking in stroke. My honours project was also one of my first clinical exposures to people who had experienced stroke. I saw patients who had severe difficulties using their arm and hand demonstrate absolute determination to turn up day-in-day-out and give it their all. It was so inspiring that I wanted to develop and test treatments that could enhance their recovery and fill the gap in our clinical understanding.

I was drawn to research because you can push boundaries, unlike in clinical practice when there are often constraints.

Do you have any tips for anyone who wants to go into research?

Find your passion, because you commit a lot of your time to research so you have to have work on something that really matters to you and to patients.

Find good mentors. Create a network of people who can support you and help you grow as a researcher.

Become resilient. Take every opportunity as a learning experience, because there are many things that will challenge you - from paper rejections to grant rejections and the like.

Stay connected with the people whose lives you are trying to change, in my case stroke survivors. Talk with them, because they can give you more insight in to stroke than you might ever have.

Do you take PhD students?

Yes! If you’re interested in the biology of stroke recovery, particularly with a rehabilitation focus, come join us. If you’ve just got a cracking idea, pitch it - we need big thinking in stroke so if you have a big idea, bring it to us!

If you would like to contact Kate Hayward about her research or potential projects, you can email her at kate.hayward@florey.edu.au.