Summary: New research suggests that signs of Alzheimer’s disease can be detected in the blood of people aged 40 and older. Finnish scientists discovered elevated levels of a biomarker associated with Alzheimer’s disease in middle-aged adults, especially those with kidney disease, in the breast milk.
These findings suggest that blood testing could provide earlier and more targeted prevention in the future, even when symptoms are still mild. However, more research is needed to establish standards and prevent misdiagnosis before blood testing becomes routine.
Important facts:
- Biomarkers associated with Alzheimer’s disease begin to appear in some people between the ages of 41 and 56.
- Elevated maternal biomarker levels and kidney disease were associated with an increased risk in the offspring.
- Blood-based biomarker tests could become a cost-effective screening tool with further validation.
Source: University of Turku
A Finnish population study suggests that signs of Alzheimer’s disease in the brain can be detected as early as middle age. In the future, blood biomarkers associated with Alzheimer’s may be able to detect it earlier. This could allow preventive treatments to be targeted to the right people, even when the disease is still in a mild stage.
As the population ages, Alzheimer’s disease and other dementias are becoming increasingly common. The pathological processes that cause symptoms begin years or decades before cognitive functions such as memory decline.
A study from the University of Turku in Finland has found that even middle-aged people can have elevated levels of blood biomarkers associated with Alzheimer’s disease. Moreover, these levels increase with age.
A new finding was that higher levels of biomarkers in parents, especially mothers, were associated with higher levels of biomarkers in middle-aged children. Additionally, the researchers discovered that kidney disease, even in middle age, may be associated with higher biomarker levels.
The APOE ε4 gene, which increases the risk of Alzheimer’s disease, was associated with higher levels of blood biomarkers in old age, but not yet in middle age.
A blood sample could help diagnose Alzheimer’s disease in the future.
Recently, it has become possible to identify biomarkers associated with Alzheimer’s disease using a blood sample. In the future, this will offer a cost-effective way to identify people at high risk of developing Alzheimer’s and prioritize their preventive treatment.
“In clinical practice, imaging or cerebrospinal fluid sampling is currently required to detect beta-amyloid pathology associated with Alzheimer’s disease. However, recently developed, highly sensitive measurement technologies make it possible to detect brain biomarkers related to Alzheimer’s disease in blood samples,” said Suvi Rovio and investor at the Prevent Research Center. Cardiovascular Medicine at the University of Turku, who led the study.
It is not yet possible to definitively diagnose Alzheimer’s disease using a blood sample, as this method is still limited by the lack of known reference values. Furthermore, it is not clear what confounding factors affect the blood concentration of Alzheimer’s-related biomarkers. Interpretation of biomarkers obtained from a blood sample can therefore lead to misdiagnosis.
“To reliably use blood-based biomarkers for the diagnosis of Alzheimer’s disease in the future, further research is needed to standardize reference values across different populations and age groups,” emphasized Rovio.
The study measured biomarkers associated with Alzheimer’s disease in blood samples from middle-aged participants (ages 41 to 56) and their parents (ages 59 to 90), with a total sample size of 2,051 people.
“Until now, brain biomarkers associated with Alzheimer’s disease have mainly been studied in older adults. Our study provides new insights into biomarker levels and associated factors from middle age onwards,” said Marja Heskinen, principal investigator at the Research Center for Applied and Preventive Cardiovascular Medicine at the University of Helsinki.
The study is part of a national study on cardiovascular risk in young Finns, coordinated by the Research Center for Applied and Preventive Cardiovascular Medicine at the University of Turku, Finland.
The results of this study were published in the journal Lancet Healthy Longevity.
About this Alzheimer’s disease research news
Author: Tuomas Koivula
Source: University of Turku
Contact: Tuomas Koivula – University of Turku
Image: The image is credited to StackZone Neuro
Original Research: Open access.
“Factors related to blood-based biomarkers for neurodegenerative diseases and their intergenerational associations in the Young Finns Study: a cohort study” by Suvi Rovio et al. Lancet Healthy Longevity
Abstract
Blood biomarkers of neurodegenerative diseases and factors related to their interindividual associations in the Young Fins Study: a cohort study
Background
Blood biomarkers (BBMs) of neurodegenerative disorders are increasingly becoming cost-effective tools for the differential diagnosis of Alzheimer’s disease and other forms of dementia. Little is known about the factors that explain differences in BBMs between population groups, and their interethnic associations are unknown.
The aim of this study was to characterize the distribution of BBM within a population-based cohort, to examine a broad range of factors associated with BBM in both middle and old age, and to examine inter-ethnic associations of BBM.
Methods
We measured BBM by detecting amyloid β and tau pathologies, including amyloid β42, amyloid β40, and phosphorylated Tau (pTau)-217, as well as glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) in 1237 subjects (age 41–56 years) and their parents (n = 814, age 59–90 years) using the Quanterix Simoa HD-X analyzer.
Standard statistical methods were used to examine the relationship between BBM and age, sex, genetic factors, a wide range of cardiometabolic markers, liver and kidney function, and lifestyle factors, as well as inter-ethnic associations.
Recommendations
Older age was associated with unfavorable BBM concentrations. Of the various factors examined, the strongest associations with unfavorable BBM concentrations were found for parental APOE ε4 carriage (amyloid β42:40 ratio, pTau-217, and GFAP) and elevated serum creatinine concentrations in both generations (pTau-LAP, GAP217).
Several factors related to glucose metabolism and dyslipidemia were negatively associated with all BBM (body mass) values, but adjustment for BMI weakened many of these associations. Statistically significant intergenerational correlations ranged from 0.20 to 0.33 and were observed primarily between mothers and children for pTau-217, GFAP, and NfL. No intergenerational correlations were observed for amyloid β42:40 ratio.
Interpretation
We have identified several factors that may influence BBM levels, including parenteral delivery. For reliable use of BBM in clinical practice, it is important to determine which factors are associated with β-amyloid and tau pathology, and which factors influence BBM levels through other physiological processes.
Funding
The Research Council of Finland, the Social Insurance Institution of Finland, competitive state funding for research in the field of specialist responsibility from the Kuopio, Tampere and Turku University Hospitals, the Juho Vannuo Foundation, the Paavo Nurmi Foundation, the Finnish Foundation for Cardiovascular Research, the Finnish Cultural Foundation, the Sigrid Jusinos Foundation, the Sigrid Tampere and Turku University Foundation, the Yrjö Jansen Foundation, the Signe and Ane Gyllenberg Foundation, the Jenny and Antti Wihuri Foundation, the Diabetes Research Foundation of the Finnish Diabetes Association, EU Horizon 2020, the European Research Council, the Tampere University Hospital Support Foundation, the Finnish Association for Clinical Chemistry, the Jane and Aatos Finish Brain Foundation and the Aatos Finish Foundation.
