A seizure is a sudden, uncontrolled electrical disturbance in the brain that can cause changes in behavior, movements, feelings, or levels of consciousness. While seizures can affect individuals at any point in life, their initial appearance in older adults, particularly without any previous history, often signals an underlying medical condition requiring specific attention. This phenomenon, known as new-onset seizures in the elderly, is a growing area of focus in neurological health.
Understanding Seizures in Older Adults
The aging brain undergoes several physiological changes that can increase its susceptibility to seizures, effectively lowering the seizure threshold. These changes include age-related brain atrophy, which alters brain structure, and shifts in neurotransmitter systems that influence neuronal excitability.
Seizures in older adults often present differently than in younger individuals, making them more challenging to recognize. Instead of classic convulsive movements, an older person’s seizure might manifest subtly as periods of confusion, staring spells, or repetitive, non-purposeful behaviors. This atypical presentation can sometimes lead to misdiagnosis, with symptoms being attributed to other conditions common in older age, such as dementia or the normal aging process. Therefore, recognizing these subtle signs is important for timely and accurate diagnosis.
Common Medical Conditions Leading to Seizures
New-onset seizures in older adults are frequently a symptom of underlying medical conditions, with several being particularly common. Cerebrovascular diseases, especially stroke, represent the leading cause, accounting for a significant percentage of new cases. Both ischemic strokes and hemorrhagic strokes can lead to seizures, sometimes occurring years after the initial event as a form of post-stroke epilepsy.
Neurodegenerative diseases also contribute substantially to seizure risk in the elderly. Conditions like Alzheimer’s disease and other dementias can increase the likelihood of seizures. Brain tumors, both primary and metastatic, are another important consideration, as they can irritate brain tissue and trigger electrical disturbances.
Traumatic brain injury, even seemingly minor head injuries sustained many years prior, can create a predisposition to late-onset seizures. The brain’s response to such injuries can alter neuronal pathways over time, fostering an environment conducive to seizure activity. Additionally, central nervous system infections, such as meningitis or encephalitis, can cause inflammation and damage that directly provoke seizures. Prompt identification and treatment of these infections can help mitigate seizure risk.
Less Common or Indirect Causes
Beyond the most prevalent medical conditions, several other factors can trigger new-onset seizures in older adults. Metabolic imbalances are a notable category, including electrolyte disturbances such as low sodium (hyponatremia) or abnormal blood sugar levels (hyperglycemia or hypoglycemia). Kidney failure or liver failure can also lead to the accumulation of toxins that disrupt brain function and induce seizures.
Medication side effects or interactions are increasingly recognized as a cause, especially given the prevalence of polypharmacy in the elderly. Certain prescription drugs, including some antidepressants, antipsychotics, and antibiotics, can lower the seizure threshold. The combined effect of multiple medications can further heighten this risk, requiring careful medication review.
Alcohol withdrawal in individuals with chronic alcohol use can also precipitate seizures, often occurring within hours to days after cessation. Vascular malformations, such as arteriovenous malformations or cavernous malformations, represent structural anomalies that can disrupt normal brain electrical activity. Although less frequent, certain autoimmune conditions affecting the brain can induce inflammation and neuronal damage, leading to seizures.
Navigating Diagnosis and Next Steps
When an older adult experiences a new-onset seizure, a thorough medical evaluation is important to identify the underlying cause. The diagnostic process typically begins with a detailed medical history, gathering information about the seizure event itself and any other health conditions or medications. A physical and neurological examination helps assess overall health and brain function.
Blood tests are commonly performed to check for metabolic issues, infections, or other systemic conditions that might be contributing to seizures. Brain imaging, such as a magnetic resonance imaging (MRI) scan, is important to look for structural problems like a stroke, tumor, or evidence of past traumatic brain injury. A computed tomography (CT) scan may also be used, though MRI generally provides more detailed images of brain tissue.
An Electroencephalogram (EEG) is a diagnostic tool that measures and records the brain’s electrical activity, helping to detect abnormal patterns indicative of seizures. Given that seizures in the elderly can be subtle or atypical, repeat or prolonged EEG studies may be necessary if initial findings are inconclusive. New-onset seizures in older adults warrant immediate medical attention to determine the cause and guide appropriate management.