Finger-Prick Blood Test Shows Promise for Early AD Detection

 Does your competent? doctor even know of the need for this test? 

So, EXACT DEMENTIA PREVENTION PROTOCOLS CAN BE INITIATED! NO? So, you do have an incompetent? doctor? 

You need this prevention!

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1. A documented 33% dementia chance post-stroke from an Australian study?   May 2012.

2. Then this study came out and seems to have a range from 17-66%. December 2013.`    

3. A 20% chance in this research.   July 2013.

4. Dementia Risk Doubled in Patients Following Stroke September 2018  

The latest here:

Finger-Prick Blood Test Shows Promise for Early AD Detection

New research provides more evidence that dried blood samples collected from a simple finger prick can be used to measure key biomarkers of Alzheimer’s disease (AD).

In a multicenter study of more than 300 participants, levels of p-tau217 in finger-prick samples closely matched results from standard blood tests, and they could identify AD-related changes in spinal fluid with an accuracy of 86%.

“These findings underscore the potential of dried blood collection and capillary blood as a minimally invasive, scalable approach for AD biomarker testing in research settings. Yet, further refinement of collection and analytical protocols is needed to fully translate this approach to be viable and useful as a clinical tool,” the investigators cautioned. 

For now, “what we have shown is that it’s an extremely useful research tool, and we already have large scale research studies going on, but we don’t envision this anytime soon to be a clinical test,” Nicholas Ashton, PhD, senior director of the Banner Fluid Biomarker Program, Banner Sun Health Research Institute in Sun City, Arizona, told Medscape Medical News.

The study was published online on January 5 in Nature Medicine. A Close Match

Blood biomarkers, p-tau217 in particular, have emerged as accurate tools for detecting AD pathology, offering a minimally invasive alternative to PET or lumbar puncture. Yet, standard blood testing still depends on venipuncture, controlled processing, and trained personnel, limiting scalability.

The DROP-AD project is evaluating whether AD biomarkers can be reliably measured from dried blood spot or dried plasma spot, derived from capillary blood obtained via finger prick, for detecting AD biomarkers, including p-tau217, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL).

The current study included 337 participants recruited across seven European centers, spanning cognitively normal individuals, patients with mild cognitive impairment, AD dementia, non-AD dementias, and individuals with Down syndrome. A total of 304 participants provided paired capillary dried plasma or blood spot samples, as well as venous plasma samples.

Levels of p-tau217 in the finger-prick samples closely matched results from standard venous blood samples (Spearman’s rank correlation coefficient = 0.74; P < .001).

Dried plasma spot p-tau217 levels increased progressively across clinical disease stages and showed “good accuracy” in predicting CSF biomarker positivity, with an area under the curve of 0.864.

Home-Based Sampling?

The investigators also successfully detected GFAP and NfL from dried blood and plasma spot analysis.

“Both GFAP and NfL showed high concordance between capillary and venous samples, and were similarly associated with cognitive performance and age, reinforcing the validity of these remote sampling methods,” the authors reported.

Notably, the study also demonstrated feasibility in individuals with Down syndrome, a population at high genetic risk for AD for whom venipuncture can be particularly challenging. 

In the subgroup with Down syndrome, capillary biomarker concentrations were higher in those with dementia than in asymptomatic individuals and showed strong agreement with venous plasma levels.

The study also found “high concordance” between supervised and unsupervised blood collections, suggesting that remote or home-based sampling may be feasible.

Not Ready for Clinical Use

The findings build on earlier data from the DROP-AD project, as reported by Medscape Medical News.

“Despite the promise shown, we do not currently recommend the use of dried blood analysis for clinical use, decision-making, or patient management because of observed differences in analytical performance and diagnostic accuracy between capillary-derived and venous blood samples,” the authors cautioned.

Further methodological refinement, standardization, and validation in larger cohorts are required before this approach can be translated into routine clinical practice, they concluded.

Once that happens, Ashton said he could envision a “scenario in the future” where elderly asymptomatic individuals could be sent a dried blood spot card as a “first step in triage.”

“Especially if we get a readout next year, or even this year, that antiamyloid drugs are beneficial to people without symptoms because these individuals are not going to be walking into our clinics in primary care or specialty services because they don’t have objective memory concerns,” Ashton said.

Having an at-home test could help engage asymptomatic people with positive biomarkers in early treatment, he added.

Worth Further Study

Reached for comment, Maria C. Carrillo, PhD, Alzheimer’s Association chief science officer and medical affairs lead, said blood-based biomarkers are “reshaping how we identify, diagnose, and understand Alzheimer’s disease, especially in research settings.”

“Currently, the evidence supports the use of blood biomarkers as one tool of many in a multi-phase diagnostic process in people experiencing changes in memory and thinking abilities. The science is not yet strong enough to recommend blood tests as a standalone diagnostic, nor for their use in people without symptoms,” Carrillo told Medscape Medical News.

The association’s clinical practice guideline provides clear, evidence-based recommendations for when and how blood-based biomarker tests can be responsibly integrated into diagnostic workflows in specialty care, she noted.

Carrillo said the Alzheimer’s Association “agrees with the authors that more research is needed before this [finger-prick] technique can become a suitable tool for clinicians.”

However, the finding that the biomarker results were very similar between the supervised and self-collected blood samples “shows that the idea has merit and is worth further investigation — in a variety of locations and situations, and with much larger and more representative populations — to help ensure that the test results are credible and consistent wherever they are done.”

Summing up, Carrillo said, “The approach described in this new paper points to a future where Alzheimer’s biomarker testing is simple, minimally invasive, widely available, and potentially even self-administered.”

The study had no commercial funding. Ashton reported receiving consultancy and/or speaker fees from Alamar Biosciences, BioArctic, Biogen, Eli Lilly, Neurogen Biomarking, Roche, Spear Bio, Quanterix, and Vigil Neuroscience. A complete list of author disclosures is provided with the original article. Carrillo had no relevant disclosures.