Even though a seizure can be caused by conditions ranging from drug or alcohol withdrawal to stroke, most people associate this surge of electrical activity in the brain with epilepsy.
Now: An increasing body of scientific evidence links seizure activity to Alzheimer’s disease. This area of research is so important that it was a major focus of the 2019 Alzheimer’s Association International Conference (AAIC) in Los Angeles.
With estimates showing that up to 16 million Americans will be diagnosed with Alzheimer’s disease by 2050—and still no cure or effective therapy to slow it down—researchers hope that early treatment of seizure activity may offer a new way to stop the progression of this relentless disease.
What you need to know…
A Different Type Of Seizure
Seizures occur in about 10% to 22% of people with Alzheimer’s, according to research published in JAMA Neurology. These seizures are often less dramatic than commonly known seizures that involve erratic movements and loss of consciousness.
In Alzheimer’s patients who have seizures, their symptoms, including the classic loss of memory and other mental abilities, known as cognitive impairment, are typically more severe.
Cognitive impairment also may occur about five to seven years earlier in these people than in those with Alzheimer’s and no seizures. In individuals with early-onset Alzheimer’s, for example, which can begin in one’s 50s, the likelihood of having seizures is more than 25%.
At the AAIC, research was presented showing that seizures can occur even before other cognitive impairment symptoms are noticeable. For example, a study of close to 300,000 US veterans found that vets over age 55 who had a first seizure had twice the risk of developing Alzheimer’s disease within nine years. This research had not been published at the time that it was presented at the AAIC.
Other studies presented at the conference found that…
- Alzheimer’s patients are over six times more likely to have seizures than older adults without Alzheimer’s.
- Alzheimer’s seizures are more likely to be recurrent. Two-thirds of patients have a second seizure within eight months.
- The longer a person has Alzheimer’s disease, the higher the risk for seizures.
A Trigger Or A Symptom?
Even though the most recent research suggests that seizures can occur before Alzheimer’s disease symptoms become apparent, it’s not clear whether the seizure is a trigger, a symptom or a risk factor for a more accelerated form of Alzheimer’s. It is known, however, that the accumulation of abnormal proteins called amyloid plaques and tau tangles in the brains of people with Alzheimer’s destroy brain cells—and loss of brain cells can lead to abnormal brain activity and seizures.
Interestingly, even before seizures develop, 42% of people with Alzheimer’s disease (some of whom did not have apparent memory problems) had abnormal brain waves detectable on an electroencephalogram (EEG), known as subclinical epileptic activity, versus 10% of study participants without Alzheimer’s, according to research published in Annals of Neurology.
As scientists try to sort out the role that seizures play in people with Alzheimer’s, the best explanation for now is that the abnormal brain waves of preclinical epilepsy are an early result of Alzheimer’s disease. These changes can lead to seizures that cause more damage and speed up the progression of Alzheimer’s. As Alzheimer’s worsens, it can lead to more seizures…and more damage—in short, a vicious cycle.
What Should You Do?
If you or a loved one has early-stage Alzheimer’s—or a diagnosis of mild cognitive impairment (which may become Alzheimer’s)—be on the lookout for any seizure activity. These seizures, especially the early ones, may not be the classic grand mal type of epileptic seizure, usually marked by a fall, loss of consciousness and uncontrollable muscle jerking.
Instead, it may be a type of seizure called a partial seizure, which is easy to miss. This type of seizure may be just a brief period (a few minutes) of staring off into space…being confused or unresponsive…fumbling…stumbling…or losing the ability to speak.
Any such behavior should be reported to your primary care physician. An EEG may show abnormal brain waves that indicate seizure activity. If this is the case, a neurologist can be consulted, and antiseizure medication may be prescribed.
Important: Because there are many causes of seizures, any type of seizure activity in an older adult (with or without Alzheimer’s) needs to be evaluated. Don’t assume that a seizure in an older person means a future diagnosis of Alzheimer’s disease.
Currently, there is no evidence that treating a new seizure in a person without Alzheimer’s will stop the disease from developing. However, researchers say that any patient with Alzheimer’s who has a seizure should be treated, since seizures may make the disease worse.
Promising treatment: A study led by researchers at Beth Israel Deaconess Medical Center (BIDMC) in Boston and published in Journal of Alzheimer’s Disease found that brain wave activity returned to a more normal pattern in early-stage Alzheimer’s patients with subclinical epileptic activity who received a single dose of the antiseizure drug levetiracetam (Keppra). Their cognitive function did not improve, but this was not expected after a single treatment.
The BIDMC researchers have received funding from the National Institutes of Health to conduct a larger and longer study in which they hope to find that treating preclinical epilepsy will not only restore normal brain waves but improve or delay cognitive decline. In past studies, levetiracetam and another antiseizure drug, lamotrigine (Lamictal), were found to be more effective at controlling Alzheimer’s seizures than phenytoin (Dilantin) and other older antiepileptic drugs.
Bottom line: Any seizure in a person with Alzheimer’s disease should be recognized and treated. Future studies should tell us if treating seizure activity can alter the course of Alzheimer’s—something that would be a big breakthrough for this baffling disease. Levetiracetam is currently the best established therapy for seizures in people with Alzheimer’s disease.