Aims: Several studies have shown that seizures and epilepsy have a higher incidence in Alzheimer’s disease (AD) than in the general population, even though with contrasting data (1), and the prevalence/ incidence of interictal epileptiform discharges (IEDs) in AD is still unclear. The aims of our study were: 1) to analyse the prevalence of seizures in a group of AD patients, 2) to investigate the prevalence/types of IEDs, 3) to assess whether IEDs/seizures occurrence correlate with any clinical features of patients. Materials: We included 167 patients with probable AD according to NIA-AA (2011), mild/moderate dementia, from a total sample (n = 245) of consecutive demented outpatients seen at the Memory Center of the University of Pisa. Exclusion criteria where CDR>2, vascular lesions or other relevant CT/MRI lesions potentially affecting seizure threshold.In a subgroup of AD patients a further diagnosis of mixed dementia (MD) with mild-moderate vascular burden was performed by the mFazekas scale score. Detailed clinical/treatment data were collected. A validated questionnaire for anamnestic seizures screening (SQ)(2) to identify previous seizures of patients was administered to patients and caregivers; SQ was administered also to caregivers (controls). 85 patients were randomized for standard EEG recording blindly to their SQ. Method: Cross-sectional analysis and correlation of collected data. Results: Age was 72,73 ± 6,52 y at AD onset, and 76,92 ± 6,38 y at observation; mean MMSE was 17,63 ± 6,03. 19.8% of patients had MD. A positive SQ was found in 12,6% AD and 1,8% controls (p < 0.01). A higher prevalence of neuroleptic intake in the previous 3 months was found among patients with positive SQ than in those with no previous seizures (p = 0.009). Seizures reported were tonic-clonic generalized (52,38%), partial complex (42,86%), and simple partial ones (33,33%) (often co-existing). Seizures prevalence/types were similar in AD with and without MD. IEDs occurred in 14.12% of patient EEG (sharp-waves: 75%; spikes: 18%; spike-waves complexes: 8%) and were mainly focal/multifocal. In patients without IEDs, cognitive impairment was higher than in those with EEG IEDs (p = 0.017). Discussion: We confi rmed AD is associated with higher risk of seizures. As seizure prevalence was similar in AD with and AD without MD we speculate that AD pathology is per se a crucial risk factor for seizures. The inverse relation between IEDs occurrence and cognitive decline might be in line with some data in AD experimental models. Conclusion: This cross-sectional study shows that AD pathology increases seizure and IEDs prevalence.

Occurrence of seizures and EEG interictal epileptiform discharges in AD patients and their correlation with clinical features: a cross-sectional study

Giorgi, Fs;VERGALLO, ANDREA;BALDACCI, FILIPPO;BONANNI, ENRICA;BONUCCELLI, UBALDO
2016-01-01

Abstract

Aims: Several studies have shown that seizures and epilepsy have a higher incidence in Alzheimer’s disease (AD) than in the general population, even though with contrasting data (1), and the prevalence/ incidence of interictal epileptiform discharges (IEDs) in AD is still unclear. The aims of our study were: 1) to analyse the prevalence of seizures in a group of AD patients, 2) to investigate the prevalence/types of IEDs, 3) to assess whether IEDs/seizures occurrence correlate with any clinical features of patients. Materials: We included 167 patients with probable AD according to NIA-AA (2011), mild/moderate dementia, from a total sample (n = 245) of consecutive demented outpatients seen at the Memory Center of the University of Pisa. Exclusion criteria where CDR>2, vascular lesions or other relevant CT/MRI lesions potentially affecting seizure threshold.In a subgroup of AD patients a further diagnosis of mixed dementia (MD) with mild-moderate vascular burden was performed by the mFazekas scale score. Detailed clinical/treatment data were collected. A validated questionnaire for anamnestic seizures screening (SQ)(2) to identify previous seizures of patients was administered to patients and caregivers; SQ was administered also to caregivers (controls). 85 patients were randomized for standard EEG recording blindly to their SQ. Method: Cross-sectional analysis and correlation of collected data. Results: Age was 72,73 ± 6,52 y at AD onset, and 76,92 ± 6,38 y at observation; mean MMSE was 17,63 ± 6,03. 19.8% of patients had MD. A positive SQ was found in 12,6% AD and 1,8% controls (p < 0.01). A higher prevalence of neuroleptic intake in the previous 3 months was found among patients with positive SQ than in those with no previous seizures (p = 0.009). Seizures reported were tonic-clonic generalized (52,38%), partial complex (42,86%), and simple partial ones (33,33%) (often co-existing). Seizures prevalence/types were similar in AD with and without MD. IEDs occurred in 14.12% of patient EEG (sharp-waves: 75%; spikes: 18%; spike-waves complexes: 8%) and were mainly focal/multifocal. In patients without IEDs, cognitive impairment was higher than in those with EEG IEDs (p = 0.017). Discussion: We confi rmed AD is associated with higher risk of seizures. As seizure prevalence was similar in AD with and AD without MD we speculate that AD pathology is per se a crucial risk factor for seizures. The inverse relation between IEDs occurrence and cognitive decline might be in line with some data in AD experimental models. Conclusion: This cross-sectional study shows that AD pathology increases seizure and IEDs prevalence.
2016
https://content.iospress.com/journals/journal-of-alzheimers-disease/52/s1
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11568/823695
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