This Biomarker May Predict Your Alzheimer’s Disease Risk

  • Researchers say they have discovered that a biomarker detected in the blood may indicate the risk of developing Alzheimer’s disease.
  • Deaths related to Alzheimer’s disease have increased by over 30% from 1999 to 2019.
  • There is no cure for the disease.

Researchers from the National University of Ireland Galway and Boston University say they have discovered a biomarker found in the blood that might help identify those at the highest risk for developing Alzheimer’s disease years before symptoms begin to show.

The study was recently published in the Journal of Alzheimer’s Disease.

According to the Centers for Disease Control and Prevention (CDC), deaths related to Alzheimer’s disease increased 33 percent from 1999 to 2019.

For this study, lead study author Emer McGrath, PhD, Associate Professor at the College of Medicine Nursing and Health Sciences at NUI Galway, told Healthline that the team analyzed blood samples from 52 healthy adults, who were later examined by specialized brain PET scans.

The adults were participating in the Framingham Heart Study, a decades-long study originally started by the National Heart, Lung, and Blood Institute in the U.S.

The blood samples were taken from people who showed no symptoms of cognitive decline and had tested at a typical level for cognition at that time.

The specialized PET scans were conducted an average of seven years after blood testing. These special scans can detect how much of an abnormal protein called ß-amyloid is detected in the brain.

This protein is associated with an increased risk of Alzheimer’s disease.

The researcher’s analysis found elevated levels of a biomarker called P-tau181 were associated with a greater accumulation of ß-amyloid, likely meaning an increased risk of Alzheimer’s disease.

According to researchers, further analysis found this biomarker outperformed two others in predicting future signs of ß-amyloid on brain scans.

“Preliminary data already showed a strong association between P-tau181 and risk of progressing to dementia in people with mild cognitive impairment,” said McGrath. “In addition, studies of patients with dementia and autopsy series to date have shown higher levels of P-tau181 in those with dementia compared to those without.”

She emphasized that this study adds to existing evidence by demonstrating a significant association between having P-tau181 and the risk of building up abnormal amyloid protein in the brain.

McGrath pointed out that identifying the disease at a preclinical stage before the onset of memory problems means having the opportunity to modify the course of the disease. There currently is no cure for the disease, but there are a few treatments that can help symptoms.

“We need valid, accessible, and convenient biomarkers for dementia, and in particular preclinical dementia, so that we can accurately and reliably predict individuals who are at high risk of developing dementia,” said McGrath.

McGrath explained that her findings could potentially improve how we detect and treat the condition.

“This biomarker could be used to identify people likely to develop dementia prior to the onset of any cognitive symptoms such as memory problems or changes in behavior,” she said. “For example, it could potentially [be] used as a screening blood test in primary care practices down the line.”

However, McGrath cautioned that further studies are needed to identify the appropriate cut-off values for blood tests so those at high risk for developing dementia can be distinguished from those at low risk.

She added that P-tau181 could also be used to identify participants for clinical trials of upcoming new therapies.

“Most of the risk of developing AD [Alzheimer’s disease] can be attributed to genetics, especially first-generation relatives of patients diagnosed with early-onset dementia are at an increased risk of AD,” said Ishwara Sankara, MD, a Neurointensivist at Texas Health Harris Methodist Hospital Fort Worth and Texas Health Physicians Group

According to Sankara, there are risk factors that can be changed to reduce our risk.

“Modifiable risk factors can include cerebrovascular disease, diabetes, hypertension, obesity, and dyslipidemia, especially if developed in mid-life (those less than 50 years old) have also been linked to an increased risk of AD development,” he said.

Sankara noted that patients with a history of traumatic brain injury or even physical and mental inactivity are also at higher risk of developing AD.

Sankara said while there are no disease-modifying cures for AD yet, experts are hopeful experimental drugs may prove effective in the future.

“Some research drugs in the pipeline are promising,” he continued. “Unfortunately, none of the drugs tested to date in clinical trials have been shown to change the course of the disease.”

Working out and being active have been shown to delay the development or progression of AD.

“Regular exercise with healthy eating habits can help reduce an individual’s risk of AD,” he said.

“Controlling modifiable risk factors, such as high blood pressure, diabetes, and cholesterol, with tobacco cessation,” he added, “have all been shown to help delay AD development.”

Researchers discovered a marker in some people’s blood that could predict who will develop Alzheimer’s disease up to seven years before symptoms develop.

Experts say this discovery might allow doctors to change the course of the disease or even stop it.

They also say that there are lifestyle changes we can make to slow the progression of the disease or significantly reduce the risk of developing AD.