Initial Sign of Alzheimer's Disease Discovered

Decreased blood flow to the brain was found to be the first sign of Alzheimer’s disease.

Researchers were able to identify the initial physiological signs of Alzheimer’s disease through the use of various imaging techniques for a study published by Nature Communications.

Although many studies have analyzed Alzheimer’s disease progression, late-onset Alzheimer’s disease (LOAD) is complicated, and only a limited scope of research has been done.

“The lack of an integrative understanding of LOAD pathology, its multifactorial mechanisms, is a crucial obstacle for the development of effective, disease-modifying therapeutic agents,” said paper first author Yasser Iturria Medina, PhD.

In the study, researchers examined more than 7700 brain images from 1171 patients in different stages of the disease. Imaging techniques, such as magnetic resonance imaging (MRI) and positron emission tomography (PET) were used.

Researchers measured amyloid concentration, glucose metabolism, blood flow, function, and atrophy in the brain. The researchers also examined blood and cerebrospinal fluid.

Each biological factor was recorded over a 30-year period. They discovered that the initial sign of Alzheimer’s disease is decreased blood flow to the brain.

The study noted that an increase of amyloid protein was previously thought to be the initial sign. Researchers also found that altered cognition started earlier than previously believed.

In the future, researchers are planning to determine the causes of each mechanism, which could lead to better treatments, and possibly even prevention.

“This is a computational, mathematical challenge that goes beyond anything we've done so far,” said lead researcher Alan Evans, PhD. “Our goal is to go to a high-level, causal modeling of the interactions amongst all of the factors of disease, but you need huge computational power to do that. It's our job to be ready with the software, the algorithms, and the data while we wait for the hardware to appear.”

However, researchers state that additional informational studies are needed.

“We still need more data-driven integrative studies, capable of considering all possible biological factors involved, as well as of clarifying the direct interactions among these factors,” Dr Medina concluded. “Without that, we cannot dream of effective treatments. We would continue to work in the dark.”