Imagine you are in your 60s and have lived with epilepsy for years. You take your medication, and your seizures are under control. But lately, you worry about your memory. You forget names. You lose track of conversations. You wonder: Is this just normal aging, or is something else happening?
A new study looks at this exact worry. It finds that many older adults with epilepsy have signs in their blood that point to a higher risk of dementia, including Alzheimer’s disease.
This matters because people with epilepsy are already known to have a higher chance of memory problems. But until now, we did not have a clear picture of what is happening inside the brain as they age.
Memory loss is not just a normal part of getting older.
Why This Risk Is Harder to See in Epilepsy
Epilepsy affects about 3 million adults in the United States. As people live longer, more are reaching older age with the condition. Doctors have noticed that older adults with epilepsy are more likely to develop dementia. Some studies suggest the risk is two to four times higher.
But here is the challenge: The brain changes that lead to dementia can be hidden. Seizures, medications, and other health issues can make it hard to tell what is causing memory problems. Doctors need better tools to spot the risk early.
Right now, most dementia tests are designed for the general population. They may not work as well for people with epilepsy. This study tries to change that.
A New Way to Map Brain Changes
Researchers used a framework called AT(N). Think of it like a map of the brain’s health. Each letter stands for a type of protein or change that can signal trouble:
- A is for amyloid, a sticky protein that builds up in Alzheimer’s disease.
- T is for tau, another protein that tangles and damages brain cells.
- N is for neurodegeneration, which means brain cells are dying or shrinking.
Doctors can now measure these markers in blood. This is less invasive than brain scans or spinal fluid tests. The study looked at three blood markers: amyloid ratio, p-tau181 (a form of tau), and neurofilament light chain (NfL, a sign of nerve damage).
The researchers grouped participants into three categories: normal, AD-continuum (on the path to Alzheimer’s), and non-AD pathologic change (other brain problems).
What the Study Looked At
The study included 84 older adults with focal epilepsy. Their average age was 66. They came from the Brain Aging and Cognition in Epilepsy (BrACE) study. None were selected for memory problems. The goal was to see how common these brain changes are in a typical epilepsy clinic.
Doctors measured blood biomarkers and tested thinking skills using two tools: the International Classification of Cognitive Disorders in Epilepsy (IC-CoDE) and the Montreal Cognitive Assessment (MoCA). They also looked at memory using a word-list test, where patients recall words after a delay.
Most Older Adults With Epilepsy Show Brain Changes
Here is what they found. Only 32% of participants had normal biomarkers. The rest had signs of brain trouble. Thirty-seven percent were on the AD-continuum, and 31% showed non-AD pathologic change.
People with normal biomarkers were younger and had epilepsy for a shorter time. Those with a gene called APOE-epsilon4, which raises Alzheimer’s risk, were more common in the AD-continuum group.
Early-onset epilepsy (starting at age 55 or older) was linked to a much higher chance of abnormal biomarkers. These patients had more amyloid, higher p-tau217, and more nerve damage.
But here is the catch: When doctors grouped patients into the three AT(N) categories, they did not find a clear link to overall thinking skills. However, when they looked at the level of p-tau181 in the blood, they found a link to memory. Higher p-tau181 meant worse word-list recall.
This does not mean this treatment is available yet.
Why One Marker Tied to Memory, But Not the Grouping
Think of it like a traffic jam. The AT(N) categories are like saying “the highway is busy.” But the p-tau181 level is like measuring how fast each car is moving. One gives a broad view; the other gives a precise detail.
In this study, the broad categories did not match memory scores. But the precise p-tau181 level did. This suggests that for people with epilepsy, we may need to look at individual markers, not just groups.
The study also found something interesting when they swapped NfL for hippocampal volume (a brain scan measure). With this change, 48% of participants looked normal, compared to 32% before. Only 15% fell into the non-AD group, down from 31%. This shows that different tests can give different answers, and we need to be careful about which ones we use.
What Experts Think About These Findings
The researchers say these results show that the AT(N) framework, designed for Alzheimer’s, does not fit perfectly for epilepsy. The patterns are more mixed. Some people have amyloid and tau problems. Others have signs of nerve damage without those proteins. This means we need epilepsy-specific tools to measure dementia risk.
They also point out that blood tests are promising but still evolving. More research is needed to see if these markers can predict who will develop dementia and who can be helped with early treatment.
If you or a loved one has epilepsy and worries about memory, talk to your doctor. Ask about cognitive screening. Blood tests for dementia risk are not yet standard care, but they may become available in the future.
For now, the best steps are to control seizures, manage other health conditions like high blood pressure, and stay mentally active. These habits support brain health at any age.
This study was small, with only 84 participants. It focused on one type of epilepsy (focal epilepsy) and may not apply to everyone. The findings are from a single point in time, so we do not know how these biomarkers change over years. More research is needed to confirm these results.
What Happens Next
Researchers plan to follow these participants over time to see who develops dementia and how the biomarkers change. Larger studies are underway to test whether blood-based tests can guide treatment. In the meantime, doctors are learning how to use these tools in epilepsy care. It may take several years before these tests are routine, but the path is becoming clearer.