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A roadmap to prepare New Zealand for an ALZHEIMER’S BLOOD TEST One of the Neurological Foundation’s inaugural Programme Grants supports a national effort to bring New Zealand closer to the next era of dementia care – simple blood tests that could detect Alzheimer’s changes in the brain, even before symptoms begin. W ith dementia projected to cost New Zealand $5.9 billion by 2050, the potential for a blood test could save money and improve lives. The programme’s name says it all: “A New Frontier in Alzheimer’s Diagnosis in New Zealand”. A dream team of clinicians, scientists, Māori health leaders, and international collaborators has been assembled to advance the cause. The programme is a national effort co-led by Dr Erin Cawston (Auckland), Associate Professor Joanna Williams (Dunedin) and Dr Campbell Le Heron (Christchurch). “This programme launches at a pivotal moment in the evolution of Alzheimer’s disease diagnosis. Our research will make sure New Zealand keeps pace with these advances, while tailoring them to our local needs,” says Dr Erin Cawston, a diagnostic neurochemistry researcher at the University of Auckland’s Centre for Brain Research (CBR). Erin is New Zealand’s leading expert in the detection of blood biomarkers for Alzheimer’s disease using Single Molecule Array (Simoa) technology. This ultra-sensitive platform detects minute concentrations of proteins in the blood that reflect what scientists know about how Alzheimer’s changes the brain. Only in the past decade have scientists developed methods to identify markers in blood that indicate the formation of damaging amyloid plaques – a hallmark of Alzheimer’s disease – making this a transformative and rapidly-evolving field. And New Zealand has an ace up its sleeve. At the heart of the effort is the nationwide Dementia Prevention Research Clinics (DPRCs), which have quietly built a comprehensive collection of dementia data and blood samples. Building on a decade of groundwork Established nine years ago and led by Professor Lynette Tippett, the DPRCs follow more than 450 volunteers with and without memory problems. Over time, some have memory changes and others do not. Detailed information is gathered on brain function, lifestyle, genetics, health, brain imaging, and PET scans. Crucially, a library of blood samples has been collected from over 240 participants, with some people having samples taken over eight years. “This rich, long-term data set enables us to see who progresses to Alzheimer’s disease and who doesn’t, and how that correlated with blood markers, providing the foundation to validate new diagnostic tools,” Erin says. The blood biobank is growing. At the end of 2016 it contained 28 samples from 28 participants. This has since grown to over 1,000 samples, meticulously stored, tracked and coded. Only small amounts of blood are needed from each sample to run large-scale tests in the lab. A multipronged approach The five-year programme will support how this groundbreaking blood biomarker testing can be rolled out nationally, integrating Māori perspectives and tikanga, evaluating the economic impact, and maximising the opportunity for new research avenues and discovery. With strong educational and outreach components, the initiative will also provide a training ground for emerging scientists and clinicians. How does the blood test work? “We know that in Alzheimer’s, two proteins – amyloid- β and tau – gradually accumulate in the brain,” Erin explains. However, there are also other processes going on in the brain and the body such as inflammation and damage to the connections between brain cells. These changes can begin many years before memory symptoms appear. Although damage begins in the brain, it leaves ‘markers’ in the blood. If the presence of a marker called p-tau217 changes, that signals there is likely some amyloid build-up. It’s not just about diagnosing Alzheimer’s. A simple blood draw can be used as a triage tool, identifying who is likely Headlines 5