The study population consisted of 480 patients with Alzheimer’s disease (AD). Females constituted 60% of the total number of the patients. The age of the patients range from 65 year to 98 year. During the period of follow up out of 480 patients 48 were labeled as epileptic (10%). 10% of our patients have positive family history of Alzheimer’s disease (AD). Almost 10% of our studied group experiences repeated attacks of convulsions during the first two years after being diagnosed as having Alzheimer’s disease. Generalized epilepsy was observed in 30 patients (62%) while focal epilepsy was reported in 18 patients (58%).
Out of 48 patients with Alzheimer’s disease and epilepsy only 10 patients (20%) had abnormal EEG. Abnormal Brain MRI in form of cerebral atrophy (mainly front parietal) was observed in 60 % of patients with Alzheimer’s disease and epilepsy.
Seizure is a sudden disruption of the brain's normal electrical activity accompanied by altered consciousness and/or other neurological and behavioral manifestations. Epilepsy is a condition characterized by recurrent seizures. The most important classification depends on the clinical presentation and spread of electrical activity e.g. generalized epilepsy or focal epilepsy. Epilepsy is either; idiopathic when there is no underlying cause or secondary if there is an underlying cause. Underlying factors can be identified in a greater proportion of elderly patients than younger patients, including cerebrovascular disease, trauma, dementia and tumors, a significant portion (one- third to one-half) are of unknown etiology.
Alzheimer’s disease (AD) is a chronic neurodegenerative disease that usually starts slowly and gradually worsens over time. It is the cause 0f 60% of cases of dementia. The disease process is associated with plaques and neurofibrillary tangles in the brain. The cause of Alzheimer’s disease is poorly understood except for 1%-5% of cases where genetic differences have been identified (autosomal dominant inheritance).
Our study is a multicenter study, two referral charity clinics, one private neurological clinic and two neurological hospitals. Almost 480 patients with Alzheimer’s disease (AD) were included in the study. Like what was mentioned in the literature 60% of our patients were female. The sex and gender gap is clearly clinically relevant when it comes to dementia care and health policy. The influences on observed sex and gender differences are complex. There are many factors which are likely contributing to this puzzle, relating to both sex (reproduction, sex hormones), gender (social roles, identities and opportunities) and the interaction between the two (e.g. epigenetic). Some researchers argue that sex differences in AD is due to the fact that women live longer than men and since AD incidence and prevalence increase with age so more women would live long enough to develop dementia. The age distribution of our study group range from 65-98 years. Most individuals with the disease are 65 or older, although individuals may develop familial or early onset Alzheimer’s disease, as early as their 30s and 40s.The likelihood of developing Alzheimer’s disease double about every five years after age 65.After the age 85,the risk reaches nearly 50 percent so the greatest risk factor for Alzheimer’s disease is advanced age. The vast majority of Alzheimer’s disease cases have a late onset disease. The Average life expectancy after diagnosis is eight to ten years. In some cases however, it can be as short as three years or as long as twenty years.
During the period of the follow up out of 480 patients, 48 labeled as epileptic (10%).this is similar to what was mentioned in the literature. Alzheimer disease (AD) and epilepsy are disorders commonly seen in the elderly. From a clinical aspect, patients with AD have an increased risk of developing seizures and epilepsy; thus AD may be an important cause of epilepsy in the elderly. Compared with healthy individuals of the same age, patients with sporadic AD have a 6- to 10-fold increased risk of developing clinical seizures during the course of their illness. In early-onset familial AD (EOFAD), epilepsy occurs more often than in sporadic AD. Seizure prevalence seems to increase with AD duration. AD severity seems to constitute another risk factor for seizures. People who have AD in combination with a seizure disorder suffer greater cognitive decline and more rapid progression of symptoms than those with AD alone. Patients with Alzheimer’s disease should be assessed carefully for epileptiform activity and silent seizures if they present with fluctuations in cognition, rapidly progressive cognitive decline.
Characterization of the clinical manifestations of seizures is usually based on information derived from the patient or the caregiver. The diagnosis of seizures in patients with AD is not always easy, there are many difficulties in establishing the diagnosis in this group of patients, since confirmation of a seizure requires a consistent clinical history which is difficult to achieve in patients with a dementia condition owing to difficulties remembering and/or reporting the event.
Generalized epilepsy was found to be the most common type among our studied group, there are few studies in the literature evaluating what type of seizures happen more often in AD. It was stated that both generalized seizures and complex partial seizures(focal with impairment) are likely to occur, but focal seizures with/without secondary generalization tend to predominate. In the predominant seizure subtype in patients with Alzheimer’s disease (non-motor complex partial seizures), some symptoms of these seizures can overlap with cognitive features of Alzheimer’s disease, but they can often be distinguished as epileptic events by their recurrent and stereotyped nature, and supported by epileptiform activity on EEG.
Like what was reported by researchers worldwide a small number of our patients exhibited EEG abnormalities. The sensitivity of scalp EEG recordings to detect epileptiform activity depends on the type of EEG protocol that is used. In patients with Alzheimer’s disease, epileptiform activity is commonly detected in electrodes that surround frontotemporal and temporal brain regions. EEG in patients with dementia and epilepsy may well be less important in the determination of type of epilepsy. Like what was reported by other researchers a considerable number of our studied group showed an evidence of brain atrophy when they were examined using Brain MRI. A brain scan using magnetic resonance imaging (MRI) is generally included in the standard evaluation for Alzheimer's disease and other forms of dementia. This scans can also show the loss of brain mass associated with Alzheimer's disease. Beta-amyloid, considered a hallmark of the disease, show up as dark areas in MRI scans of the brain. AD is characterized by an insidious onset and inexorable progression of atrophy that is first manifest in the medial temporal lobe. The entorhinal cortex is typically the earliest site of atrophy, closely followed by the hippocampus, amygdala, and parahippocampus. MRI can measure the size and amount of cells in the hippocampus, an area of the brain that typically shows atrophy (shrinkage) during the course of Alzheimer's disease. MRI scans of the brain with Alzheimer's disease may also show parietal atrophy. The parietal lobe of the brain is located in the upper back portion of the brain and is responsible for several different functions including visual perception, ordering and calculation, and the sense of our body's location. In the early stages of Alzheimer's disease, an MRI scan of the brain may be normal.
Conclusion: Patients with Alzheimer’s disease have an increased risk of developing epilepsy. There is strong relation between disease duration and development of epilepsy.