Understanding What Causes Seizures Late in Life?

According to Johns Hopkins Medicine, the incidence of epilepsy is highest among older adults, with each decade after 60 bringing more new cases. Understanding what causes seizures late in life is crucial for proper diagnosis and effective management, distinguishing these episodes from other age-related health issues.

Quick Summary

Experiencing a seizure for the first time in later years is often a symptom of an underlying health problem, most commonly a cerebrovascular event like a stroke, a neurodegenerative disorder such as dementia, or the presence of a brain tumor.

Key Points

• Underlying Conditions: Seizures late in life are rarely spontaneous and often signal an underlying medical issue, most commonly stroke or dementia.

• Stroke is a Major Culprit: Cerebrovascular disease is the leading cause of late-onset epilepsy, with damaged brain tissue acting as a focal point for seizure activity.

• Brain Tumors are a Possibility: Both benign and malignant brain tumors can cause seizures by affecting nearby brain cells and require medical evaluation.

• Metabolic Factors Matter: Electrolyte imbalances (like low sodium) and hypoglycemia (low blood sugar) are common triggers in older adults due to other health conditions.

• Medication Check is Essential: Polypharmacy and the side effects of certain medications can increase seizure risk in seniors and require careful management.

• Prompt Evaluation is Key: Any new seizure in an older adult warrants a full medical workup, including imaging, to determine the cause and prevent recurrence.

Introduction to Late-Onset Seizures

Seizures are abnormal, uncontrolled electrical disturbances in the brain that can cause a wide range of symptoms, including changes in awareness, behavior, and movement. While epilepsy is often associated with childhood, it has a surprisingly high incidence rate in older age, a phenomenon known as late-onset epilepsy (LOE). For older adults, a seizure is not a disease in itself but rather a symptom of another condition. The causes are often acquired and linked to the cumulative effects of life on the brain.

Leading Neurological Causes in Older Adults

Cerebrovascular Disease and Stroke

This is the most common cause of seizures in older adults. A stroke, which can be ischemic (blocked artery) or hemorrhagic (bleeding), causes damage to brain tissue. The resulting scar tissue or damage can disrupt normal electrical signaling, leading to seizures. Studies have shown that seizures can occur both shortly after a stroke (early-onset seizures) or much later, even years down the line (late-onset seizures), as the brain continues to heal and scar.

Neurodegenerative Disorders

Conditions that cause progressive damage to the brain can increase the risk of seizures. This includes:

• Alzheimer's Disease and Dementia: The degeneration of brain cells associated with these diseases can create an environment where abnormal electrical activity is more likely. Seizures can be an early or late symptom.
• Parkinson's Disease: While less common than with dementia, seizures can occur as a complication of the disease or its treatment.

Brain Tumors

Whether benign or malignant, brain tumors can cause seizures by putting pressure on brain tissue, irritating neurons, or disrupting the brain's normal electrical pathways. The presentation of a seizure can sometimes be the first noticeable symptom of a brain tumor in an older adult.

Systemic and Metabolic Triggers

Electrolyte Imbalances and Hypoglycemia

Seniors are more susceptible to metabolic disturbances that can lower the seizure threshold. These can include:

• Hyponatremia (low sodium): Often caused by dehydration, kidney problems, or certain medications.
• Hypoglycemia (low blood sugar): A significant risk for older adults with diabetes, especially if medication dosage is incorrect or meals are missed. The brain is highly dependent on glucose for energy.

Infections

Infections that affect the central nervous system can cause inflammation and swelling, leading to seizures. Examples include:

• Meningitis
• Encephalitis
• Septicemia (blood infection) that spreads to the brain

Drug Effects and Polypharmacy

As older adults often take multiple medications for various chronic conditions, the risk of drug interactions and side effects increases. Certain drugs can lower the seizure threshold, while withdrawal from others, particularly benzodiazepines or alcohol, can trigger seizures. Polypharmacy, the use of multiple medications, is a significant risk factor. It is crucial for healthcare providers to review a senior's full medication list, including over-the-counter drugs and supplements, when evaluating a seizure.

Traumatic Brain Injury

Head injuries, which can result from falls—a common occurrence in the elderly—can lead to seizures. The risk can persist for months or even years after the initial injury, as the brain heals and scars. Even seemingly minor head trauma should be taken seriously in older adults.

Comparing Common Late-Onset Seizure Causes

Cause	Mechanism for Seizures	Typical Onset	Diagnostic Clues
Stroke	Creates damaged, scarred brain tissue that disrupts electrical signaling.	Can be early (within days) or late (years after).	History of cerebrovascular event; focal seizures common.
Dementia	Progressive brain cell degeneration increases vulnerability to abnormal electrical activity.	Often in later stages of the disease progression.	Presence of cognitive decline; may be subtle or unprovoked.
Brain Tumor	Mass presses on or infiltrates brain tissue, irritating neurons.	Can be the first noticeable symptom.	Focal seizures that progress or change; may have other neurological deficits.
Electrolyte Imbalance	Disrupts ionic concentrations needed for proper neuronal function.	Acute and often tied to a specific health event (dehydration, illness).	Sudden onset; often resolves when imbalance is corrected.
Infection	Inflammation and swelling of brain tissue due to viral, bacterial, or parasitic agents.	Can be acute, alongside other signs of illness (fever, confusion).	Accompanied by other systemic or neurological infection symptoms.

Diagnostic Evaluation

If an older adult has a seizure, a thorough medical evaluation is necessary to determine the cause. This process involves:

1. Comprehensive Medical History: Gathering information on past medical conditions, falls, strokes, and all current medications.
2. Physical and Neurological Examination: Assessing cognitive function, coordination, and reflexes.
3. Electroencephalogram (EEG): A test to measure brain wave activity, which can help identify abnormal electrical patterns.
4. Brain Imaging: MRI or CT scans are used to look for structural abnormalities like tumors, stroke damage, or evidence of infection. A brain scan is almost always recommended for late-onset seizures to rule out a structural problem. For more information on the diagnostic process, consult reputable medical resources like the Epilepsy Foundation.
5. Laboratory Tests: Blood work can check for metabolic issues, infections, and medication levels.

Conclusion

While the onset of seizures late in life can be alarming, they are most often a symptom of an underlying medical issue rather than an isolated event. Identifying what causes seizures late in life is the critical first step toward effective treatment. Common culprits include cerebrovascular disease, neurodegenerative conditions, brain tumors, metabolic disorders, and medication issues. A comprehensive and prompt medical evaluation is essential for accurate diagnosis and for creating an appropriate care plan to manage the underlying condition and improve the senior's quality of life.

Frequently Asked Questions

Can a person develop epilepsy late in life without any history?

Yes, it is possible for an individual to develop epilepsy later in life, even without a prior history of seizures. This is known as late-onset epilepsy and is often triggered by an acquired condition such as a stroke, brain tumor, or neurodegenerative disease.

What is the most common cause of seizures in older adults?

The most common cause of seizures in older adults is cerebrovascular disease, particularly stroke. The brain damage and scarring that result from a stroke can interfere with normal brain function, leading to seizures.

How are seizures in seniors different from those in younger people?

Seizures in older adults are often focal, starting in a specific part of the brain and sometimes progressing. They may also present more subtly, with confusion or behavioral changes rather than full-blown convulsions, which can be mistaken for other age-related issues.

Can medication cause seizures in the elderly?

Yes. Older adults who take multiple medications (polypharmacy) are at a higher risk of drug interactions and side effects. Certain medications can lower the seizure threshold, making seizures more likely.

What should be done after an older person has a first-time seizure?

Immediate medical attention is crucial. After the seizure, a doctor will conduct a thorough evaluation, including reviewing medical history, performing a physical exam, and ordering diagnostic tests like an EEG and brain imaging to determine the underlying cause.

Is Alzheimer's disease linked to seizures in later life?

Yes, neurodegenerative diseases like Alzheimer's and other forms of dementia are associated with a higher risk of seizures, especially in the later stages. The progressive damage to brain cells contributes to abnormal electrical activity.

How can you help prevent seizures in seniors?

Prevention focuses on treating the underlying cause. Strategies include managing chronic conditions like diabetes and hypertension, regular medication reviews to avoid harmful interactions, and addressing lifestyle factors like sleep deprivation and stress. Ensuring a safe environment to prevent falls is also important.