Newswise — WINSTON-SALEM, N.C. – Oct. 25, 2023 – Researchers at Wake Forest University School of Medicine have received a five-year, $9 million grant from the National Institute on Aging, part of the National Institutes of Health, to create a national consortium that will study the use, interpretation and implementation of biomarkers to diagnose Alzheimer’s disease.

According to the Alzheimer’s Association, more than 6.5 million Americans are living with Alzheimer’s disease, and around 60% of older adults who have the disease or related dementias also have three or more chronic conditions. These chronic conditions can make a diagnosis challenging. 

“Biomarkers can assist with a diagnosis, but there are still many unanswered questions regarding their accuracy and when they should be used in primary care,” said Michelle M. Mielke, Ph.D., professor of epidemiology and prevention at Wake Forest University School of Medicine and the study’s principal investigator. 

Current biomarkers to detect the build-up of abnormal amyloid protein in the brain, a key hallmark of Alzheimer’s disease, include a lumbar puncture to test for proteins in cerebrospinal fluid (CSF) or amyloid Positron Emission Tomography (PET) imaging. However, these biomarkers are more costly and invasive than a blood draw and are often not readily accessible to many patients. There are a limited number of dementia specialists so most patients with cognitive impairment will be treated in primary care. Blood Alzheimer’s biomarkers are becoming available for clinical use, but it is not known how to incorporate them to establish a diagnosis in primary care and when additional confirmation such as CSF or PET is needed.  

Mielke said much more research is needed on how and when blood-based biomarkers should be used, especially among diverse populations of older adults. 

“Multiple chronic conditions and frailty, which are known risk factors for Alzheimer’s disease, can also impact the expression of Alzheimer’s disease pathology,” Mielke said. “Specifically, these conditions can impact cognitive function, which can make a diagnosis difficult.”

According to Mielke, chronic conditions such as kidney disease or obesity can also elevate or lower biomarker levels and potentially lead to a false positive or negative result. More research is needed to understand when to use and how to interpret the blood biomarkers older adults with other or multiple chronic conditions.  

With the funding, Mielke’s team will support the creation of the Alzheimer’s Diagnosis in Older Adults with Chronic Conditions (ADACC) Network, which will be comprised of multiple sites and a multi-disciplinary team of investigators. The network will have three primary objectives:

Establish a data coordinating center to identify and assemble existing Alzheimer’s disease and related dementias observational and real-world cohorts, representative of older adults living with multiple chronic conditions.

Examine the performance and accuracy of the blood biomarkers in older adults with multiple chronic conditions.

Develop recommendations for how and when blood biomarkers should be used in primary care in older adults with multiple chronic conditions for the diagnosis of Alzheimer’s disease and related dementias.

The consortium will be created in collaboration with multiple institutions across the United States. In addition to Mielke, there are three co-principal investigators: 

  • Jeff Williamson, M.D., professor and chief of gerontology and geriatric medicine at Wake Forest University School of Medicine and clinical director of the medical school’s Sticht Center for Healthy Aging and Alzheimer’s Prevention

  • Nicole R. Fowler, Ph.D., director of research for internal medicine and geriatrics at Indiana University (IU) School of Medicine and associate director of the IU Center for Aging Research at the Regenstrief Institute.

  • Thomas K. Karikari, Ph.D., assistant professor of psychiatry and director of the Biofluid Biomarker Laboratory and the Alzheimer's Disease Research Center Biomarker Core at the University of Pittsburgh and scientist, Clinical Neurochemistry Laboratory at the University of Gothenburg in Sweden.

“We’re assembling a talented and multidisciplinary team to examine how and when to incorporate Alzheimer’s biomarkers from a variety of perspectives,” Mielke said. “Our goal is to develop evidence-backed strategies and guidelines to inform providers and patients on the use and implementation of biomarkers among older adults with multiple chronic conditions and cognitive impairment. This work could lead to an earlier diagnosis and advance care.”