Summary: A new method of examining blood plasma allowed researchers to identify specific chemical bonds within the blood. The new technique allowed researchers to accurately distinguish between Alzheimer’s disease and Lewy body dementia, thus reducing cases of misdiagnosis.
Source: Lancaster University.
Alzheimer’s sufferers may now have an additional test to improve the accuracy of diagnosis in order to better tailor appropriate treatment.
In the largest and most conclusive study of its kind, researchers have analysed blood samples to create a novel and non-invasive way of helping to diagnose Alzheimer’s disease and distinguishing between different types of neurodegenerative disorders.
Following this breakthrough discovery, Alzheimer’s sufferers may now have an additional test to improve the accuracy of diagnosis in order to better tailor appropriate treatment.
The research also offers a valuable opportunity to monitor the progression of the disease.
The international study in the Proceedings of the National Academy of Sciences used sensor-based technology with a diamond core to analyse approximately 550 blood samples.
By passing light through the diamond and observing its interactions with the blood plasma, researchers were able to identify specific chemical bonds within the blood. This biochemical data was used to compare blood samples from cases of Alzheimer’s disease and other neurodegenerative diseases with those from healthy controls.
The ground-breaking scientific investigation was carried out by researchers at Lancaster University, the University of Central Lancashire (UCLan), the University of Manchester and the Federal University of Rio Grande do Norte, Brazil.
Professor David Allsop from Lancaster University has been collaborating for many years with Professor David Mann at Manchester University in searching for diagnostic markers for neurodegenerative disease in blood plasma.
They provided all of the plasma samples for the study, along with supporting clinical and genetic information, and expertise in Alzheimer’s and other neurodegenerative conditions.
Professor Allsop said: “A particularly exciting aspect of the study was the ability to distinguish accurately between Alzheimer’s disease and Lewy body dementia, which are conditions that both result in dementia and can be difficult to separate from each other based on clinical information and symptoms. By reduction of misdiagnosed cases and administration of appropriate treatment, many people could benefit from this type of blood test in the future.”
Alzheimer’s diagnosis currently involves careful medical evaluation including clinical history, memory testing and brain scans, yet the only conclusive diagnosis is determined by post-mortem examination. This new blood test offers a non-invasive, more accurate and relatively cost-effective method of diagnosis, which will ensure the correct management of the condition.
Professor Francis Martin, principal investigator of the study and Biosciences theme lead at UCLan, said: “We have an aging population, meaning that the incidence and prevalence of Alzheimer’s is increasing, as is the need for accurate diagnosis. The ability to identify different neurodegenerative diseases through the analysis of blood offers a faster and accurate way of establishing the most effective treatment plan as well as disease monitoring.”
This new approach could also offer potential for carrying out tests to identify and monitor early signs of mild cognitive impairment, meaning that the onset of Alzheimer’s and other types of neurodegenerative diseases could be detected early and intervention measures could be put in place earlier to slow the progress of these diseases.
Professor Martin added: “For those suffering with Alzheimer’s disease, the damage is already well advanced once conventionally diagnosed, but this new method offers a potentially effective early screening tool when patients are only demonstrating signs of mild cognitive impairment. This is a potentially significant breakthrough for the prevention of different debilitating and chronic neurological diseases.”
Source: Gillian Whitworth – Lancaster University
Image Source: NeuroscienceNews.com image is credited to Lancaster University.
Original Research: Full open access research for “Differential diagnosis of Alzheimer’s disease using spectrochemical analysis of blood” by Maria Paraskevaidi, Camilo L. M. Morais, Kássio M. G. Lima, Julie S. Snowden, Jennifer A. Saxon, Anna M. T. Richardson, Matthew Jones, David M. A. Mann, David Allsop, Pierre L. Martin-Hirsch, and Francis L. Martin in PNAS. Published online September 5 2017 doi:10.1073/pnas.1701517114
Differential diagnosis of Alzheimer’s disease using spectrochemical analysis of blood
The progressive aging of the world’s population makes a higher prevalence of neurodegenerative diseases inevitable. The necessity for an accurate, but at the same time, inexpensive and minimally invasive, diagnostic test is urgently required, not only to confirm the presence of the disease but also to discriminate between different types of dementia to provide the appropriate management and treatment. In this study, attenuated total reflection FTIR (ATR-FTIR) spectroscopy combined with chemometric techniques were used to analyze blood plasma samples from our cohort. Blood samples are easily collected by conventional venepuncture, permitting repeated measurements from the same individuals to monitor their progression throughout the years or evaluate any tested drugs. We included 549 individuals: 347 with various neurodegenerative diseases and 202 age-matched healthy individuals. Alzheimer’s disease (AD; n = 164) was identified with 70% sensitivity and specificity, which after the incorporation of apolipoprotein ε4 genotype (APOE ε4) information, increased to 86% when individuals carried one or two alleles of ε4, and to 72% sensitivity and 77% specificity when individuals did not carry ε4 alleles. Early AD cases (n = 14) were identified with 80% sensitivity and 74% specificity. Segregation of AD from dementia with Lewy bodies (DLB; n = 34) was achieved with 90% sensitivity and specificity. Other neurodegenerative diseases, such as frontotemporal dementia (FTD; n = 30), Parkinson’s disease (PD; n = 32), and progressive supranuclear palsy (PSP; n = 31), were included in our cohort for diagnostic purposes. Our method allows for both rapid and robust diagnosis of neurodegeneration and segregation between different dementias.
“Differential diagnosis of Alzheimer’s disease using spectrochemical analysis of blood” by Maria Paraskevaidi, Camilo L. M. Morais, Kássio M. G. Lima, Julie S. Snowden, Jennifer A. Saxon, Anna M. T. Richardson, Matthew Jones, David M. A. Mann, David Allsop, Pierre L. Martin-Hirsch, and Francis L. Martin in PNAS. Published online September 5 2017 doi:10.1073/pnas.1701517114