Mendez Mario, Lim Gerald
Department of Neurology, The University of California at Los Angeles, Los Angeles, California 90073, USA.
Drugs Aging. 2003;20(11):791-803. doi: 10.2165/00002512-200320110-00001.
Epileptic seizures occur in patients with dementia at a higher prevalence than among healthy elderly individuals. The incidence of seizures among patients with dementia varies with the aetiology of the dementing illness. In patients with Alzheimer's disease (the most common form of dementia), approximately 10-22% have at least one unprovoked seizure. Seizures usually occur in later stages of Alzheimer's disease, on average, > or =6 years into the course of the disease. Seizures in Alzheimer's disease are more likely to occur with early-onset disease, particularly if there is a familial presenilin I mutation. The incidence of seizures in other dementing diseases is less clear. There are special considerations regarding the management of seizures in the elderly with dementia. First, the presence of cognitive impairment may impede an accurate diagnosis of seizures. Clinicians may also mistake seizure manifestations for symptoms of the underlying dementia. Second, since most dementia patients are elderly, there are pharmacokinetic changes with aging that affect the use of antiepileptic drugs. Third, antiepileptic drugs have potential cognitive adverse effects that may worsen dementia. Although few studies are available, extrapolations from research in young people and elderly patients without dementia provide several recommendations for the management of seizures in patients with dementia: exclude symptomatic causes of seizures before committing to antiepileptic drug therapy; treat after a first seizure if there is evidence of focal neurological involvement or a risk of recurrent seizures; use antiepileptic drugs with minimal cognitive adverse effects, such as carbamazepine, valproic acid, gabapentin and lamotrigine; and use the lowest possible dosage and monitor antiepileptic drug levels, where possible.
癫痫发作在痴呆患者中的发生率高于健康老年人。痴呆患者中癫痫发作的发生率因痴呆疾病的病因不同而有所差异。在患有阿尔茨海默病（最常见的痴呆形式）的患者中，约10%-22%至少有一次无诱因发作。癫痫发作通常发生在阿尔茨海默病的后期，平均而言，在疾病进程≥6年时出现。阿尔茨海默病中的癫痫发作更易发生于早发型疾病，特别是存在家族性早老素I突变时。其他痴呆疾病中癫痫发作的发生率尚不清楚。对于老年痴呆患者的癫痫管理有一些特殊考虑。首先，认知障碍的存在可能妨碍对癫痫发作的准确诊断。临床医生也可能将癫痫发作表现误认为是潜在痴呆的症状。其次，由于大多数痴呆患者为老年人，随着年龄增长会出现药代动力学变化，影响抗癫痫药物的使用。第三，抗癫痫药物有潜在的认知不良反应，可能会使痴呆加重。尽管相关研究较少，但从针对年轻人和无痴呆的老年患者的研究推断，可为痴呆患者的癫痫管理提供一些建议：在开始抗癫痫药物治疗前排除癫痫发作的症状性病因；如果有局灶性神经受累证据或有癫痫复发风险，则在首次发作后进行治疗；使用认知不良反应最小的抗癫痫药物，如卡马西平、丙戊酸、加巴喷丁和拉莫三嗪；尽可能使用最低剂量并监测抗癫痫药物水平。
