According to a study of epilepsy and behavior, people diagnosed with late-onset epilepsy (LOE) by age 30 or older are at significantly increased risk of future stroke.
In this study, researchers from the UK and Canada conducted a systematic review of studies that reported LOE and stroke from 2014 to 2019. To identify relevant articles, they defined LOE as a diagnosis of epilepsy as early as the age of 30.
The study researchers identified a total of 5 case-control or cohort studies in which the incidence of stroke in LOE was compared with a healthy control population. They then performed a meta-analysis to determine the risk of stroke in study participants compared to those without LOE.
The meta-analysis of the pooled study data showed that patients with LOE had a significantly increased risk of a subsequent stroke compared to the control population (weighted odds ratio 3.88; 95% CI, 2.76-5.46). According to the researchers, stroke probabilities were stable over different follow-up periods as well as across different geographic regions. In studies that differentiated between ischemic stroke and ICH, the incidence of intracerebral bleeding (ICH) was disproportionately high. In addition, the results of a prospective study showed a significantly increased conversion rate to Alzheimer’s disease (AD) during the 3.5 years after the onset of the attack (conversion to dementia, 17.5%) [46% AD]) compared to patients in the control group.
The study’s researchers stated that the high incidence of stroke in patients with LOE may be due to the higher rate of cardiovascular disease risk factors in this population. These risk factors include diabetes, high blood pressure, smoking, and the apolipoprotein E4 (APOE4) allele. Physical activity and low alcohol consumption are protective risk factors that could also represent a reduced risk for LOE.
One limitation of this meta-analysis included the heterogeneity present in the studies analyzed, including the variation in LOE definitions between studies.
Based on their results, the researchers concluded that while LOE can be a point of intervention to alter the risk of stroke and dementia, additional “advances in knowledge of natural history and pathophysiology are required” through prospective studies.
Wall J, Knight J, Emsley HCA. Late-onset epilepsy predicts stroke: systematic review and meta-analysis. Published online December 14, 2020. Epilepsy Behavior. doi: 10.1016 / j.yebeh.2020.107634