A new study from Karolinska Institutet, published in Alzheimer’s & Dementia, shows that everyday health problems—like kidney function, cholesterol, and diabetes—can affect the accuracy of new blood tests for Alzheimer’s disease.
Still, the most promising blood marker remains highly reliable.
Blood-based biomarkers (BBMs) are becoming a simpler and more practical tool for diagnosing Alzheimer’s. Unlike spinal fluid tests or brain scans, these blood tests are easier to use in clinics. But many older patients also have other health conditions. Could those interfere with the results?
To answer that, researchers at Karolinska Institutet studied 311 patients from the Karolinska University Hospital Memory Clinic. They used data and blood samples from the GEDOC biobank to examine how common health issues—like vascular disease, kidney function, and cholesterol—affect Alzheimer’s biomarkers in the blood.
“We found that several health factors were linked to changes in biomarker levels,” says Makrina Daniilidou, one of the researchers. “For example, diabetes and high cholesterol affected amyloid levels, even when Alzheimer’s disease was already taken into account. This suggests the effects come from the body, not just the brain.”
One important finding was that the biomarker p-tau217, considered the most reliable, stayed accurate even when health conditions were present. However, another marker, the Aβ42/40 ratio, was more sensitive to these factors.
Why is this important? It means doctors can trust the blood tests, but they should also look at a person’s full health profile when interpreting the results. This approach may help catch Alzheimer’s earlier and make diagnosis more accurate.
“These tests are a big step forward,” says Daniilidou. “Our results show they work well, but also show that we need a more personalized way to use them.”
Next, the researchers plan to test these findings in larger groups, including healthy people at risk of dementia. The ultimate goal is to create more precise, adjusted models for Alzheimer’s diagnosis that can be used in regular healthcare settings.
If you care about Alzheimer’s, please read studies about Vitamin D deficiency linked to Alzheimer’s, vascular dementia, and Oral cannabis extract may help reduce Alzheimer’s symptoms.
For more information about brain health, please see recent studies about Vitamin B9 deficiency linked to higher dementia risk, and results showing flavonoid-rich foods could improve survival in Parkinson’s disease.
Copyright © 2025 Knowridge Science Report. All rights reserved.
