A major scientific breakthrough may help doctors detect a serious brain disease long before people notice any symptoms.
Researchers from Lund University in Sweden have developed a new test that can identify Lewy body disease in its earliest stages, offering hope for earlier treatment and better care in the future.
Lewy body disease is one of the most common brain disorders linked to dementia. Although many people are familiar with Alzheimer’s disease, far fewer have heard of Lewy body disease, even though it affects millions of people around the world. It is considered the second most common cause of dementia after Alzheimer’s disease.
The disease develops when abnormal clumps of protein build up inside the brain. These clumps are known as Lewy bodies. They are made from a protein called alpha-synuclein. Normally, this protein helps nerve cells communicate with each other. However, when it folds into an abnormal shape, it begins to stick together and form harmful deposits.
Over time, these deposits interfere with the brain’s normal function. They can damage nerve cells and affect areas of the brain responsible for memory, thinking, movement, sleep, mood, and behavior. As the damage spreads, people may develop a range of symptoms.
Lewy body disease is closely linked to both Parkinson’s disease and Lewy body dementia. Scientists now understand that these conditions are part of the same disease process. If movement problems such as tremors, stiffness, and slow movements appear first, doctors may diagnose Parkinson’s disease.
If memory loss, confusion, and thinking problems appear first, the diagnosis may be Lewy body dementia. In both cases, the underlying cause is the buildup of Lewy bodies in the brain.
One of the biggest challenges has been diagnosis. For many years, doctors could only confirm the presence of Lewy bodies by examining brain tissue after a person had died. This made it extremely difficult to identify the disease early enough to test treatments that might slow its progress.
The new study could change that. The researchers developed a test that looks for signs of Lewy body disease in cerebrospinal fluid, the clear liquid that surrounds and protects the brain and spinal cord. Because this fluid is in close contact with the brain, it can provide important clues about changes happening inside the nervous system.
The research team studied more than 1,100 adults who did not have memory problems, dementia, or movement disorders when the study began. The scientists expected to find only a small number of people with early disease changes. Instead, they discovered that around 10% of participants already showed signs of Lewy body disease in their cerebrospinal fluid.
This finding was surprising because these individuals appeared healthy. They were living normal lives and had not yet developed obvious symptoms. The results suggest that the disease may begin silently many years before doctors would normally recognize it.
As the participants were followed over time, some of those with early signs of the disease started to develop memory problems, thinking difficulties, or movement symptoms. Several were eventually diagnosed with Parkinson’s disease or Lewy body dementia. This provided strong evidence that the new test can detect the disease long before traditional diagnosis is possible.
The researchers also uncovered another important clue. Many people who tested positive for early Lewy body disease had problems with their sense of smell. Even though they felt healthy, they struggled to recognize odors correctly.
Loss of smell has long been linked to Parkinson’s disease, but this study suggests it could also serve as an early warning sign of Lewy body disease.
Because smell testing is simple and inexpensive, the scientists believe it could become a useful screening tool. Older adults who perform poorly on a smell test could then undergo more detailed testing, including the new cerebrospinal fluid test, to determine whether disease changes are already occurring in the brain.
The study revealed another interesting finding. Some participants with Lewy body disease also had abnormal levels of proteins commonly associated with Alzheimer’s disease.
These individuals tended to experience faster decline than those who had Lewy body disease alone. This information may help doctors predict how quickly symptoms could worsen and allow them to plan treatment and support more effectively.
The discovery comes at an important time. Researchers around the world are developing new therapies aimed at slowing or stopping diseases caused by abnormal protein buildup in the brain.
However, these treatments are likely to work best when given early, before extensive brain damage occurs. A reliable test that identifies people years before symptoms appear could make future treatments much more effective.
The scientists hope their work is only the beginning. They are continuing to search for ways to detect Lewy body disease through a simple blood test. While this is more challenging because the disease-related proteins are present in very small amounts in the bloodstream, advances in technology are making such tests increasingly possible.
Early detection has transformed the way doctors approach several diseases, including some cancers and Alzheimer’s disease. Researchers believe the same could eventually happen with Lewy body disease.
Detecting the condition before symptoms appear may give people more time to plan for the future, access support, participate in clinical trials, and potentially receive treatments that slow the disease.
If you care about dementia, please read studies about dietary strategies to ward off dementia, and how omega-3 fatty acids fuel your mind.
For more health information, please see recent studies about Choline deficiency linked to Alzheimer’s disease, and what to eat (and avoid) for dementia prevention.
The study was published in the journal Nature Medicine.
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