Midlife changes in Alzheimer's biomarkers may predict dementia

July 6, 2015, Washington University School of Medicine
Anne Fagan, PhD, professor of neurology (left), and Courtney Sutphen, a graduate student, are lead authors on a study showing that changes in the spinal fluid during middle age may help doctors identify people at risk of developing Alzheimer's disease later in life. Credit: Michael C. Purdy

Studying brain scans and cerebrospinal fluid of healthy adults, scientists have shown that changes in key biomarkers of Alzheimer's disease during midlife may help identify those who will develop dementia years later, according to new research.

The study, at Washington University School of Medicine in St. Louis, is published July 6 in JAMA Neurology.

"It's too early to use these biomarkers to definitively predict whether individual patients will develop Alzheimer's disease, but we're working toward that goal," said senior author Anne Fagan, PhD, a professor of neurology. "One day, we hope to use such measures to identify and treat people years before memory loss and other cognitive problems become apparent."

The study focused on data gathered over 10 years and involved 169 cognitively normal research participants ages 45 to 75 when they entered the study. Each participant received a complete clinical, cognitive imaging and cerebrospinal fluid biomarker analysis every three years, with a minimum of two evaluations.

At the participants' initial assessments, researchers divided them into three age groups: early-middle age (45-54); mid-middle age (55- 64); and late-middle age (65-74).

Among the biomarkers evaluated in the new study were:

  • Amyloid beta 42, a protein that is the principal ingredient of Alzheimer's plaques;
  • Tau, a structural component of that increases in the cerebrospinal fluid as Alzheimer's disease damages brain cells;
  • YKL-40, a newly recognized protein that is indicative of inflammation and is produced by brain cells; and
  • The presence of amyloid plaques in the brain, as seen via amyloid PET scans.

The scientists found that drops in 42 levels in the among cognitively normal participants ages 45-54 are linked to the appearance of plaques in years later. The researchers also found that tau and other biomarkers of -cell injury increase sharply in some individuals as they reach their mid-50s to mid-70s, and YKL-40 rises throughout the focused on in the study.

Previous research has shown that all of these biomarkers may be affected by Alzheimer's disease, but this is the first large data set to show that the biomarkers change over time in middle-aged individuals.

All of these changes were more pronounced in participants who carried a form of a gene that significantly increases the risk of Alzheimer's disease. The gene is known as APOE, and scientists have known that people with two copies of a particular version of this gene have up to 10 times the risk of developing Alzheimer's as those with other versions of the gene.

The data came from the ongoing Adult-Children Study at the university's Charles F. and Joanne Knight Alzheimer's Disease Research Center. Scientists have been following participants with and without a family history of the disease, with the aim of identifying Alzheimer's biomarkers most closely associated with the development of full-blown disease years later.

"Alzheimer's is a long-term process, and that means we have to observe people for a long time to catch glimpses of it in action," Fagan said.

Explore further: Alzheimer's markers predict start of mental decline

Related Stories

Alzheimer's markers predict start of mental decline

May 14, 2013
(Medical Xpress)—Scientists at Washington University School of Medicine in St. Louis have helped identify many of the biomarkers for Alzheimer's disease that could potentially predict which patients will develop the disorder ...

Brain imaging changes in individuals with Down's may help advance Alzheimer's trials

April 14, 2015
Researchers have characterized three different brain imaging changes in individuals with Down syndrome, who are at very high risk for development of Alzheimer's disease, even before the onset of progressive memory and thinking ...

Multiple pathways progressing to Alzheimer's disease

June 25, 2015
The amyloid cascade hypothesis of Alzheimer's disease (AD) posits that sticky aggregations or plaques of amyloid-beta peptides accumulate over time in the brain, triggering a series of events that ultimately result in the ...

New perspective needed for role of major Alzheimer's gene

May 7, 2013
(Medical Xpress)—Scientists' picture of how a gene strongly linked to Alzheimer's disease harms the brain may have to be revised, researchers at Washington University School of Medicine in St. Louis have found.

Alzheimer's brain change measured in humans

June 12, 2013
Scientists at Washington University School of Medicine in St. Louis have measured a significant and potentially pivotal difference between the brains of patients with an inherited form of Alzheimer's disease and healthy family ...

High blood pressure in middle age versus old age may better predict memory loss

November 13, 2013
People in middle age who have a high blood pressure measure called pulse pressure are more likely to have biomarkers of Alzheimer's disease in their spinal fluid than those with lower pulse pressure, according to research ...

Recommended for you

Meditation and music may alter blood markers of cellular aging and Alzheimer's disease

November 13, 2018
A research team led by Dr. Kim Innes, a professor in the West Virginia University School of Public Health, has found that a simple meditation or music listening program may alter certain biomarkers of cellular aging and Alzheimer's ...

Alzheimer's and cardiovascular disease share common genetics in some patients

November 9, 2018
Genetics may predispose some people to both Alzheimer's disease and high levels of blood lipids such as cholesterol, a common feature of cardiovascular disease, according to a new study by an international team of researchers ...

Artificial intelligence predicts Alzheimer's years before diagnosis

November 6, 2018
Artificial intelligence (AI) technology improves the ability of brain imaging to predict Alzheimer's disease, according to a study published in the journal Radiology.

Diabetes medications may reduce Alzheimer's disease severity

November 1, 2018
People with Alzheimer's disease who were treated with diabetes drugs showed considerably fewer markers of the disease—including abnormal microvasculature and disregulated gene expressions—in their brains compared to Alzheimer's ...

Massive study confirms that loneliness increases risk of dementia

October 29, 2018
A new Florida State University College of Medicine study involving data from 12,000 participants collected over 10 years confirms the heavy toll that loneliness can take on your health: It increases your risk of dementia ...

Bioactive compound from the Rhodiola plant improves memory

October 25, 2018
In an ageing society, more people are suffering from memory disorders. The progressive loss of memory severely impairs the quality of life of those affected. So far, no drugs are known to prevent age-related cognitive decline.

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

ronda_anderson_parsons
not rated yet Jul 07, 2015
I know first-hand just how devastating this disease can be for an individual and their family. I cared for my mother-in-law for 10 years as she drifted down through the stages of dementia. But somehow in the midst of all this sadness I was able hare joy and peace with her. I write of my experience in my book 'Creating Joy & Meaning for the Dementia Patient'. It was a true labor of love, a vow I made to myself to do everything in my power to help other caregivers. I also share my insights on my blog TheDementiaConnection.wordpress.com.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.