Abstracts

This abstract is a recipient of the Grass Young Investigator Award
This abstract has been invited to present during the Genetics & Behavior/Neuropsychology/Language platform session

Rationale: Dementia and seizures are both public health imperatives. Co-morbid seizures occur in 10%-64% of those with dementia and accelerate cognitive decline in dementia patients. However, the impact of seizures on clinical and mortality outcomes in dementia patients has not been studied. The purpose of our study is to fill this knowledge gap.

Methods: National Alzheimer’s Coordinating Center maintains a multicenter, prospective data of patients recruited at 39 Alzheimer’s disease Centers in the U.S. We analyzed longitudinal data from September 2005 through December 2021 to include all with cognitive impairment at initial visit (Figure 1A). We compared cognitive, functional and clinical status and mortality outcomes between those with and without active seizures. Active seizures were defined as seizures in the past 1 year and/or requiring active treatment.

Results: At the initial visit, among the 26,425 cognitively impaired patients, 374 (1.4% point prevalence) had active seizures. Seizure patients were significantly younger (62.91 vs. 68.4 years, p< 0.001) at the onset of cognitive decline. In a multivariate logistic regression analysis (Table 1), history of dominant Alzheimer’s disease (AD) mutation (OR:5.55, CI:2.39-12.89, p< 0.001), stroke (OR:3.17, CI:2.35-4.27, p< 0.001), TIA (OR:1.72,CI: 1.21-2.46, p=0.003), traumatic brain injury [TBI] (OR:1.92, CI:1.48-2.50, p< 0.001), Parkinson’s disease [PD] (OR:1.79,CI:1.07-2.98, p=0.025), active depression (OR:1.61, CI:1.30-1.99,p < 0.001) and lower education (OR:0.97,CI:0.95-0.99, p=0.043) were found to be associated with active seizures. _x000D_ Patients with active seizures performed worse on mini mental status examination (18.50 vs. 22.88, p < 0.001) and Clinical Dementia Rating-Sum of boxes (7.95 vs. 4.28, p < 0.001) compared to those without after adjusting for age and duration of cognitive decline in a generalized linear model. Patients with seizures had worse functional assessment scores and were more likely to have physical dependence (OR: 2.52, CI: 1.99-3.19, p< 0.001).
_x000D_ Analysis of longitudinal mortality data showed that a higher proportion of active seizure patients had died (OR: 1.56, CI: 1.27-1.91 p < 0.0001), and they were younger at death (72.99 vs. 79.72 years, p < 0.001). To examine mortality further, a multivariate survival analysis using Cox regression model was conducted to study age at death and seizure status (Figure 1B). We adjusted the model for sex, disease duration, stroke, TIA, TBI, depression, education and dominant AD mutation. Despite adjustment, patients with active seizures were at a higher risk of dying at a younger age (hazard ratio: 1.76, CI: 1.49-2.08, p < 0.001).