Incidence and Predictors of Seizures in Patients with Alzheimer's Disease

Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, USA.
Epilepsia (Impact Factor: 4.57). 06/2006; 47(5):867-72. DOI: 10.1111/j.1528-1167.2006.00554.x
Source: PubMed


To determine cumulative incidence and predictors of new-onset seizures in mild Alzheimer's disease (AD) with a cohort followed prospectively. Limited information is available on the incidence of seizures, and no reports exist of seizure predictors in AD patients.
Mild AD patients were prospectively followed at 6-month intervals to estimate incidence of unprovoked seizures, compare age-specific risk of unprovoked seizures with population norms, and identify characteristics at baseline (demographics, duration and severity of AD, physical and diagnostic test findings, and comorbid medical and psychiatric conditions) influencing unprovoked seizure risk. Review of study charts and medical records supplemented coded end-point data.
The cumulative incidence of unprovoked seizures at 7 years was nearly 8%. In all age groups, risk was increased compared with a standard population, with an 87-fold increase in the youngest group (age 50-59 years) and more than a threefold increase in the oldest group (age 85+ years). In multivariate modeling, independent predictors of unprovoked seizures were younger age [relative risk (RR), 0.89 per year increase in age; 95% confidence interval (CI), 0.82-0.97], African-American ethnic background (RR, 7.35; 95% CI, 1.42-37.98), more-severe dementia (RR, 4.15; 95% CI, 1.06-16.27), and focal epileptiform findings on electroencephalogram (EEG) (RR, 73.36; 95% CI, 1.75-3075.25).
Seizure incidence is increased in people starting with mild-to-moderate AD. Younger individuals, African Americans, and those with more-severe disease or focal epileptiform findings on EEG were more likely to have unprovoked seizures.

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Available from: Jason Brandt, Jan 08, 2014
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    • "Amongst early events linked to AD pathogenesis that can contribute to memory decline, we focused here on neuronal network hypersynchrony (Bakker et al., 2012; Vossel et al., 2013). Indeed, seizures are more frequent in AD patients than in age-matched individuals and seizures can precede the onset of memory deficits (Amatniek et al., 2006; Sanchez et al., 2012). Different lines of evidence also indicate the occurrence of hypersynchronous network activity such as seizures amongst mouse models of AD (Palop et al., 2007; Minkeviciene et al., 2009; Born et al., 2014; Ittner et al., 2014). "
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