A recent study presented at the 10th Congress of the European Academy of Neurology (EAN) highlights a significant discovery with practical implications for neuroscience, diagnostics, and metabolic research. Researchers found that a simple and inexpensive blood test—the Triglyceride-Glucose (TyG) index—can predict accelerated cognitive decline in patients with early-stage Alzheimer’s disease.

The study, conducted by a team from the University of Palermo, analyzed data from 551 individuals diagnosed with either early Alzheimer’s or mild cognitive impairment (MCI). Researchers discovered that patients with a high TyG index were four times more likely to experience rapid cognitive decline—defined as a reduction of more than 2.5 points per year on the Mini-Mental State Examination (MMSE).

What is the TyG Index?

The TyG index is a well-established marker of insulin resistance, calculated using the formula:

It’s derived from two routine fasting blood test values: triglycerides and glucose. This simplicity makes it readily available in virtually any hospital or diagnostic laboratory. Importantly, the TyG index has previously been associated with cardiometabolic conditions—but this study extends its relevance to neurological decline, particularly in biologically confirmed Alzheimer’s cases.

Implications for Alzheimer’s Research and Patient Care

This finding offers a valuable, low-cost tool to help stratify patients with early Alzheimer’s by their risk of rapid disease progression. According to lead author Dr. Bianca Gumina:

“A simple metabolic marker available in every hospital laboratory can help identify more vulnerable subjects and optimize the use of new Alzheimer's treatments.”

By incorporating the TyG index into diagnostic and monitoring protocols, clinicians and researchers may:

• Prioritize patients for early intervention, especially as new therapies become available.
• Improve clinical trial design by identifying subgroups more likely to show measurable decline.
• Explore the metabolic dimension of neurodegeneration, which remains an underused pathway in Alzheimer’s care.

Importantly, the study noted that this predictive value was not observed in non-Alzheimer’s cognitive impairments, indicating a specific link between insulin resistance and Alzheimer's pathophysiology.

Metabolic Biomarkers in Neurodegeneration: A Growing Field

The connection between insulin resistance and Alzheimer’s—sometimes called “Type 3 diabetes”—has been explored in previous research, but this study reinforces it with a clinically applicable, quantitative index. For molecular biologists, biotechnologists, and diagnostics professionals, it’s a compelling case for integrating metabolic assessments into neurobiology pipelines.

From a laboratory operations perspective, the study also illustrates how routine, reproducible tests can deliver high-impact insights when paired with innovative thinking and robust data analysis.

Reference:
European Academy of Neurology. (2025, June 22). Common blood test could predict Alzheimer’s decline. ScienceDaily. Retrieved from https://www.sciencedaily.com/releases/2025/06/250622224303.htm