Question:
My son is 59 years old and was diagnosed with Alzheimer’s probably in March 2019. Other than that he has enjoyed good health his entire life, no heart conditions, no seizures, no celiac disease. The progression of the Alzheimer’s has been accelerating in the past year. In the last month I’ve noticed some myoclonic jerks. He is very frightened of hospitals and any medical procedures. Is the risk of the myoclonic jerks developing into seizures worth putting him through the trauma of an EEG to diagnose for seizures?
Answer:
Unfortunately, seizures are a common part of Alzheimer’s disease (AD) in people with Down syndrome (DS). In a survey of our patients with DS and AD, we found that 77% had seizures. In the medical literature, the prevalence of seizures in people with DS and AD has been found to be as high at 84%.
Myoclonic epilepsy (myoclonic seizures, myoclonic jerking) is commonly the type of seizure seen in people with DS and AD. Myoclonic seizures are brief and often involve only one jerking movement of an arm or leg (although they may also involve the trunk).
However, the seizure types may range from myoclonic seizures to tonic-clonic (grand mal) seizures. Tonic-clonic seizures include shaking and stiffness, often of the whole body, and are usually associated with falling and/or a change in consciousness.
Diagnosis of seizures typically includes a history and physical exam and lab (blood) work to assess for causes. Imaging of the brain (CT scan and/or MRI) is often done, too. An EEG (electroencephalogram) may be ordered to confirm the diagnosis.
Unfortunately, EEGs may often be normal (or at least not consistent with a seizure disorder) in a person who has seizures. This is true for people with and without DS. However, it can be helpful information to have. In someone with DS and AD who may have difficulty cooperating with an EEG, I do sometimes consider skipping the EEG. Since the prevalence of seizures is so high (as it is in DS and AD), if the clinical information (history, physical, labs, and possibly imaging) are strongly indicative of a seizure, in some situations, it makes sense to consider treating for seizures without the EEG.
The first consideration for treatment is whether to treat with medications. Infrequent and mild myoclonic jerking is often well-tolerated without treatment. At times, the side effects of the medications are tolerated less than the myoclonic jerking. However, sometimes the myoclonic jerking can be poorly tolerated. For example, repeated jerking of the arm may make eating difficult or dramatic jerking of the trunk (even if only one infrequent jerk) may cause the individual to fall. Treatment may help with eating difficulty or fall prevention in those situations. Some considerations for medication are included in our online article Seizures in People with Down Syndrome and Alzheimer’s Disease. There are a variety of factors to consider regarding choice of medication and the clinician assessing the seizures will determine which medication is appropriate based on those factors.