Improving stroke diagnosis for rural and regional patients
When it comes to a stroke, timing is critical. The speed at which a patient is diagnosed and receives treatment might decide the outcome, and that puts our rural and remote communities – spread across vast distances – at a distinct disadvantage.
JCU researchers are working to identify novel blood-based markers to diagnose ischemic stroke so that appropriate, targeted treatment can be delivered to patients earlier.
Associate Dean of Research at JCU’s College of Medicine and Dentistry, Dr Joe Moxon, is leading the North Queensland Stroke Cohort project, a collaboration between JCU and Townsville University Hospital (TUH) aiming to address poor outcomes for patients with ischemic stroke.
“It’s a massive health concern,” Dr Moxon says. “12 million strokes were reported globally in 2019 and the vast majority were underpinned by interruptions to the brain's blood supply which causes cerebral ischemia.”
“Compared to other countries with comparable healthcare systems, Australia is lagging. Even with the abundant availability of chemical thrombolytic agents to treat stroke, we are not getting them to patients. Only 10 to 11% of potentially eligible patients receive this medication within the effective time window,” Dr Moxon says.
Overcoming the health access obstacles for rural communities
As is often the case in health disparities, the burden of stroke is worse outside metropolitan areas. According to a 2021 report by the Stroke Foundation, Australians living in regional and remote communities were 17 per cent more likely to experience a stroke than their city counterparts1.
Distance to care can present a major obstacle for our rural communities. While 70 per cent of acute stroke patients in urban areas can access stroke care, only three per cent of rural patients have immediate access, with many patients travelling over 200 km to reach a hospital with adequate stroke care2.
“There is a marked discrepancy between the quality of care received between rural and metropolitan patients simply because of access to care,” Dr Moxon says.
“It’s staggering to me that the Stroke Centre here in Townsville services an area of 750,000 kilometres. That’s three times the size of the country where I was born and raised (the United Kingdom). It puts into perspective the scale and practicalities involved for a patient somewhere like Normanton to get to Townsville within the treatment window,” Dr Moxon says.
Current therapeutics aim to minimise the damage caused by stroke by rapidly restoring cerebral blood flow. However, this treatment comes with an extremely narrow effective window and the risk of bleeding if administered incorrectly. It’s further complicated by a very high prevalence of ‘stroke mimics’ where patients present with nonspecific neurological symptoms, suggestive of stroke.
“It's important that we differentiate patients with true ischemic stroke from stroke mimics, and the big flaw here is that there is no blood test to diagnose stroke,” Dr Moxon says. “All patients have to undergo specialist assessment, and brain imaging to demonstrate changes to the brain, and these scans aren't widely available in regional areas. Current approaches also carry a significant chance of misdiagnosis,” Dr Moxon says.
To improve diagnosis and treatment outcomes, Dr Moxon and the North Queensland Stroke Cohort project team are investigating biomarkers unique to ischemic stroke to distinguish them from stroke mimics.
Developing the tools to administer treatments sooner
Working with the TUH Neurology, Stroke and Vascular Surgery Units, researchers have recruited patients aged over 18 years who present for assessment of symptoms suggestive of stroke which have been persistent for less than 24 hours.
“The prevalence of stroke mimics complicates matters as it means that clinicians must consider whether symptoms are due to stroke, or another condition requiring alternative treatment. So rather than comparing our stroke cohort with a healthy control group, which previous studies have done, we’ve recruited patients who have presented with suspected stroke but were later diagnosed with a stroke mimic to serve as our comparator, to better simulate the clinical challenge,” Dr Moxon says.
The team are examining mRNA and RNA to plot the differences between ischemic stroke and stroke mimics to identify a series of transcripts that could be used as a potential diagnostic panel.
“We have identified a group of blood-borne molecules that rapidly change following stroke onset. We believe that these molecules have the potential to act as biomarkers that can be measured to quickly determine whether a patient has or has not suffered a stroke. Such a test would enable doctors to administer treatment more rapidly, thereby improving outcomes for stroke-affected patients and their families,” Dr Moxon says.
Dr Moxon says they are currently corroborating their findings with other published studies and arranging to share data between institutes.
“We want to perform a meta-analysis to assess differential expression of the genes that we identified across all of the studies and test diagnostic performance to see if our findings are generally applicable.
“A major success is the ability to work with the clinicians at the hospital, and JCU bioinformaticians and molecular biologists to develop a clinically relevant patient cohort and using samples collected at that moment being able to generate high-quality sequencing data for further analysis,” Dr Moxon says.
Locally-relevant and innovative research is a part of JCU’s commitment to the health of regional, rural and remote communities. Through College-led research projects, centres of excellence and institutes like JCU’s Australian Institute of Tropical Health and Medicine (AITHM), we are discovering solutions to the health issues of most importance to tropical Australia.