Monday, May 29, 2023
Joseph Sirven, MD, from the Department of Neurology, Mayo Clinic, Scottsdale, Arizona, provided a compelling presentation demonstrating the frequency of seizure in older adults and the importance of considering seizure within a differential diagnosis.[1] Although the tendency is to make the assumption that a seizure and epilepsy are medical problems more common to the young, Sirven provided data and clinical case examples to demonstrate that seizure is increasingly common in older adults.[2]
The increased incidence of seizure in the elderly population is because seizure is a symptom of other common medical problems in older adults, including stroke, brain tumor, or head trauma. Unfortunately, due to biased beliefs and the multiple health problems seen in older adults, seizure is often missed as a diagnosis.
Nonepileptic seizures (NES) are a frequent problem in elderly patients. Compared with a younger control group, physiologic and psychogenic NES are equally frequent in the elderly. Unlike seizures in children that originate from temporal lobe foci, seizures in older adults tend to be from frontal or parietal lobe foci. These seizures tend to be more focal motor and sensory. These individuals generally present with an altered mental state, staring, blackouts, and confusion. In addition, it is not unusual for an older adult to have a simple partial seizure and present with numbness in a hand or leg.[3]
In older adults, the postictal state is prolonged in 14% of cases and may last even longer than 24 hours. After a 1-minute seizure, for example, a prolonged state of confusion, temporary paralysis, or falls can result for days or even a week. As a result, seizures can have a significant impact on quality of life among these individuals.
In almost half (49%) of all seizures in older adults, the cause is unknown. The majority of the known causes of seizure are stroke, neurodegenerative diseases such as Alzheimer's disease, trauma, tumors, metabolic disorders such as uremia, hyperglycemia, hypoglycemia, hyponatremia, alcohol withdrawal, or infection.[4] Risk factors for seizures are outlined in Table 1.
| Risk Factor | Degree of Risk for Seizure Compared With Healthy Older Adult |
|---|---|
| Stroke | 20 times |
| Dementia | 5 to 10 times |
| Trauma | 3 times |
| Alcohol | 3 times |
| Infection | 3 times |
| Depression | 6 times |
A comprehensive seizure assessment is similar in the older adult to assessment in the younger individual and includes a description of the event, exploration of risks and predisposing factors, and a physical examination with a special focus on a neurologic evaluation. Laboratory evaluation should include a complete blood count and comprehensive metabolic panel. Additional tests can be used to further establish the diagnosis such as those listed in Table 2.
| Magnetic resonance imaging (MRI) Electroencephalograph (EEG) Lab work to assess electrolyte imbalance, drug toxicities Cardiovascular testing such as electrocardiogram or echocardiogram Tilt table testing |
Syncope, transient ischemic attack (TIA), transient global amnesia (TGA), or vertigo are commonly noted to mimic seizure and complicate the differential diagnosis. The length of the episode in question is particularly important information to help with the differential diagnosis. A seizure is believed to last approximately a minute. Syncope, however, is briefer than seizure, usually lasts for less than a minute, and tends to be reproducible in the office setting. Conversely, a TIA lasts several minutes to hours. Like TIA, TGA typically lasts for hours rather than minutes.
The decision to initiate treatment with medication for a seizure should be based on evidence of recurrent seizures, onset of epilepsy as status epilepticus, or a clear structural predisposition for seizures.[4] Medication should likely be initiated if the individual has seizures that impact quality of life.
Pharmacologic interventions are the primary management of seizure disorders, and treatment choices are generally based on what is known about the seizure (eg, simple and complex partial seizures, tonic clonic, or myoclonic), the known comorbidities of the individual, and drug side effects.[4,5] The 4 newest antiepileptic drugs -- gabapentin, lamotrigine, oxcarbazepine, and topiramate -- are recommended as first treatment options.[5]
The specific risks and challenges of these drugs in older adults are related to hepatic changes and drug metabolism with age, increased likelihood of drug-drug interactions, and the inability to utilize current serum drug levels because these drug levels were developed on younger individuals.[3] Drug choices and potential side effects are shown in Table 3.
Decisions about drug use must be made based on individual needs and side effect profiles. With regard to drug dosing, the guideline is to start low and monitor drug response in terms of prevention of seizure. Extended-release formulations may be helpful with regard to drug adherence. Consideration can be given to stopping medication if the patient is free of seizures for 2 to 5 years.
Immediate treatment of seizures for institutionalized older adults can be done using valium administered as a buccal squirt or rectal suppository. Evaluation and treatment of seizures in older adults should be geared toward helping these individuals obtain and maintain optimal quality of life through seizure elimination balanced by tolerance of the medication.
| Drug | Side Effects | Indication | Advantages | Disadvantages |
|---|---|---|---|---|
| Phenytoin | Osteoporosis Rash Slowed thinking |
Partial seizure |
Low cost | Many drug interactions and food/nutrient interactions |
| Carbamazepine | Osteoporosis Rash |
Partial seizure |
Minimal sedation and cognitive adverse effects |
Ataxia, diplopia, multiple drug interactions |
| Valproic acid |
Platelet function Tremor |
Generalized seizures |
Broad spectrum efficacy | Extensive protein binding, multiple drug interactions |
| Gabapentin | Fatigue | Partial seizures |
No hepatic metabolism; drug interaction only with antacids |
Dosage modification in renal disease; TID dosing needed |
| Tiagabine | Slowed thinking Fatigue |
Partial seizures |
None | Dosage modification in liver disease |
| Lamotrigine | Prolonged half life Rash |
Partial seizures |
Interaction with antiepileptic drugs only |
Dosage modification in liver disease |
| Topiramate | Renal stones Slowed thinking |
Partial seizures |
Interaction with antiepileptic drugs only |
Weight loss; dosage modification if creatinine clearance is < 60 mL per minute |
*Optimal dosage is based on prevention of seizure and not on reaching therapeutic drug levels.
Seizure, which is a common symptom of many of the chronic illnesses experienced by the elderly, is clearly an important differential diagnosis to consider in the care of older adults. The assessment, differential diagnosis, and treatment options of seizure in older adults are no different than they are in younger individuals. Decisions to treat or not to treat the older individual, however, need to be made carefully based on the impact of the seizure on the quality of life of the individual balanced against the side effects of drug management. Using this approach to facilitate the evaluation and treatment of older adults for seizure will help nurse practitioners optimally manage this potentially devastating clinical problem and help these individual achieve optimal function and quality of life.
