Biomarkers: The Pathway to Earlier LBD Diagnosis and Better Treatments

In LBD clinical research, scientists use tests that measure both the symptoms of a disease and also what biological changes are underway. Those tests that detect the presence or progression of a biological disease process are called biomarkers.

Finding LBD biomarkers is one of the top research recommendations for LBD in the National Plan to Address Alzheimer’s Disease (and related dementias). Thanks to increases in dementia research funding, the National Institutes of Health recently funded four new LBD biomarker research studies.

While the studies all have different aims, they include a core set of physical and neurological examinations and interviews, and collection of certain biological fluid samples. Each of these studies will carefully assess people with LBD for up to five years, with the goal of reaching a better understanding of how biological changes result in the symptoms of the disease. This can ultimately lead to better diagnostic tools and treatments. These studies will also establish a new and rich resource for the LBD scientific community – a national, centralized collection of LBD clinical and biological data.

This represents a major step forward and the participation of the LBD community in these studies will be vital. This article will help you understand what clinical assessments and biomarkers are involved and how they will help advance our understanding of LBD.

LBD Biomarker Studies: What to Expect

Those who are interested in participating in LBD research can be confident that they will learn right up front exactly what tests the study includes. All research studies include a process called “informed consent” in which the person volunteering formally agrees to participate in the study. Part of the informed consent process involves a member of the study team explaining the study, any treatments or tests involved, any benefits from participating in the study, and any risks involved.

To provide the researchers with a thorough understanding of a person’s health, participants will be asked questions to set a baseline at the start of the study. This starts with their personal and family’s medical history. A simple cognitive assessment will be done, and participants will be asked basic questions about mood or behavioral changes. Blood pressure, height and weight will be taken and a neurological exam will be done to identify any changes in movement including tremor, stiffness and slowness.

The study team will then look more deeply at LBD symptoms. These assessments may take several hours, and may be administered over two sessions. Extensive cognitive testing will help measure what skills have been affected, such as memory, language, or executive function. Questionnaires will help identify the range of mood changes, like depression or anxiety, as well as psychiatric symptoms like hallucinations or delusions. A careful assessment will be done to identify if the participant has any sleep disorders. A smell test will be given to detect any loss of the ability to smell. And other tests will identify changes in the body’s ability to regulate autonomic systems like blood pressure and pulse.

Biofluids (blood, urine and cerebrospinal fluid) provide information about the presence of other medical conditions, but are also studied to find changes that are linked to LBD and related disorders. This may include changes in genetic factors or levels of certain proteins associated with neurological disorders. The presence of these biomarkers may predict future symptoms and rate of progression.

One of the most important tests in these studies is called a lumbar puncture (or spinal tap). A lumbar puncture is the only way to get direct access to spinal fluid, the clear liquid that circulates through the brain and spinal cord. This sample of fluid gives researchers the ability to measure levels of proteins produced by the brain. Examining levels of key proteins that are associated with dementia is absolutely vital to the development of new LBD diagnostic tools and treatment options, and has revolutionized the study of Alzheimer’s disease. Because it is so essential, a lumbar puncture is considered mandatory to participate in all four LBD biomarker studies.

Advances in lumbar puncture techniques have significantly reduced the risks and side effects, making an increasingly common part of cutting-edge dementia research studies. To learn more, view this 5-minute video on lumbar puncture.

Tests Unique to Certain Studies

Depending on which of the 4 studies you choose to participate in, additional assessments may be administered to answer the aims of the study. Participants may have brain scans to help detect changes in brain structure and function. A magnetic resonance imaging (MRI) scan allows researchers to see physical changes in the brain. (Examples include the brain shrinkage seen in Alzheimer’s disease or the presence of a tumor.) A second type of scan, called single photon emission computerized tomography or SPECT, is used to look at a functional change associated with LBD. A nuclear medicine compound called 123I-FP-CIT (also called DAT scan) is used with SPECT to find changes in the brain’s abilities to use a neurotransmitter called dopamine. Dopamine is important in movement and mood.

If any of the participants should happen to pass away during certain studies, their brains can be carefully examined by a highly-trained neuropathologist. At the present time, this is the only way to currently confirm the LBD diagnosis. Because these research participants will be so carefully studied for several years, researchers can combine the research data collected during life with what is seen in the brain after death. This is the most powerful information scientists can use to advance our understanding of LBD. The donation of a study participant’s brain is the “ultimate gift” a person can make to research. Learn more about brain donations and brain autopsies in this helpful article from LBDA.

Participate in Research

These studies are funded by the National Institute of Health through a program called the Parkinson’s Disease Biomarker Program (PDBP). To learn more about these studies, visit the PDBP’s website. To find research studies and clinical trials now enrolling people with LBD, visit LBDA’s Participate in Research page.