Dementia and epilepsy

The study dilemma – an introduction Dementia and epilepsy are among the most frequent medical conditions in the general population, particularly in the older adult. These conditions deserve special attention because of the demographic shift caused by the rapidly aging population. There is a striking lack of systematic longitudinal studies appropriately addressing the causal relationship between the two disorders. It is obvious that the incidence of seizures and epilepsy will vary among dementia subgroups, based on the underlying illness. To prove that the occurrence of both dementia and epilepsy in one individual is causally related is difficult and complex, as many variables which may accompany reduction of seizure threshold must be considered. These include comorbidities such as cerebrovascular disease, silent post-traumatic scars, depression, anxiety, proconvulsive medication, and metabolic disturbances. There is very little data on neuropathological findings in patients with dementia-associated seizures. Therefore, it is not surprising that controversies exist with regard to seizure prevalence, type, time course, pathophysiology, and treatment options. This review will focus on the relationship between Alzheimer's disease (AD) and seizure occurrence. There are three reasons for this: (1) AD patients most likely represent the major proportion of patients with dementia and epilepsy; (2) studies of AD patients include a greater number of patients and often include well-documented clinical and neuropathological data; and (3) there is increasing experimental evidence that seizures in AD may be a reflection of pathophysiological processes similar to or overlapping with those responsible for cognitive decline (Larner2010).