Doctors usually diagnose dementia only after memory and thinking problems become noticeable.
By that stage, damage to the brain has often been developing for many years. Scientists are therefore searching for ways to detect the disease much earlier, when treatments may have a better chance of slowing its progress.
A new study from researchers at Shandong First Medical University and Shandong Academy of Medical Sciences points to an unexpected part of the brain that may provide an early warning sign.
The focus is the choroid plexus, a small structure that produces the fluid surrounding the brain and spinal cord.
This clear fluid does much more than protect the brain from injury. It also carries nutrients, removes waste, and helps wash away proteins that may otherwise build up and damage brain cells. Problems with this cleaning system have long been suspected in Alzheimer’s disease.
The scientists analysed MRI scans from more than 45,000 adults enrolled in the UK Biobank. They carefully measured the size of the choroid plexus and examined changes in its appearance on brain scans. Participants were then followed for several years to determine who later developed dementia.
The results showed that people with an enlarged choroid plexus were significantly more likely to develop dementia in the future. Lower MRI signal intensity in the same structure also predicted poorer memory, reduced reasoning ability, and a greater risk of Alzheimer’s disease.
The researchers found another important clue. Changes in the choroid plexus were linked with brain atrophy, meaning the gradual loss of brain tissue that commonly occurs during Alzheimer’s disease. This suggests that damage to the choroid plexus may contribute to wider brain changes over time.
To better understand the relationship, the team also examined genetic information using Mendelian randomisation. Their findings supported the possibility that abnormalities in the choroid plexus may contribute directly to dementia rather than simply appearing after the disease begins.
Early identification of high-risk individuals could become increasingly important as new treatments are developed. If doctors can recognise brain changes before major symptoms appear, patients may benefit from closer monitoring, healthier lifestyles, and future therapies designed to delay cognitive decline.
The researchers plan to continue investigating how the choroid plexus interacts with other Alzheimer’s biomarkers, including amyloid and tau proteins measured in blood, spinal fluid, and specialised brain scans. Combining several biomarkers may improve the accuracy of future risk prediction.
This research offers a promising new direction for dementia detection. Its strengths include a very large study population and several complementary research methods.
The main limitation is that the findings still need confirmation in other groups of people before they can become part of routine screening. Nevertheless, the study highlights the importance of looking beyond traditional brain regions and suggests that the choroid plexus may become a valuable target for both diagnosis and future treatment research.
If you care about dementia, please read studies that eating apples and tea could keep dementia at bay, and Olive oil: a daily dose for better brain health.
For more health information, please see recent studies what you eat together may affect your dementia risk, and time-restricted eating: a simple way to fight aging and cancer.
Source: Shandong First Medical University & Shandong Academy of Medical Sciences.
