Seizure prevalence in neurodegenerative diseases-a study of autopsy proven cases

Knowledge about the seizure prevalence in the whole symptomatic course, from disease onset to death, in neurodegenerative diseases (ND) is lacking. Therefore, the aim was to investigate seizure prevalence and associated clinical implications in neuropathologically diagnosed ND.

Clinical records of cases from the Neurobiobank Munich, Germany, were analyzed. Neuropathological diagnoses of the assessed cases included Alzheimer disease (AD), corticobasal degeneration (CBD), frontotemporal lobar degeneration (FTLD), Lewy body disease (LBD), multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Seizure prevalence during the whole symptomatic disease phase was assessed and compared amongst ND. Associations between first clinical symptom and seizure prevalence and between seizures and disease duration were examined.

In all, 454 patients with neuropathologically diagnosed ND and with available and meaningful clinical records were investigated (AD, n = 144; LBD, n = 103; PSP, n = 93; FTLD, n = 53; MSA, n = 36; CBD, n = 25). Seizure prevalence was 31.3% for AD, 20.0% for CBD, 12.6% for LBD, 11.3% for FTLD, 8.3% for MSA and 7.5% for PSP. Seizure prevalence was significantly higher in AD compared to FTLD (p = 0.005), LBD (p = 0.001), MSA (p = 0.005) and PSP (p < 0.001). No other significant differences regarding seizure prevalence were found between the studied ND. Cognitive first symptoms in ND were associated with an increased seizure prevalence (21.1% vs. 11.0% in patients without cognitive first symptoms) and motor first symptoms with a decreased seizure prevalence (10.3% vs. 20.5% in patients without motor first symptoms). Seizures were associated with a longer disease duration in MSA (12.3 vs. 7.0 years in patients without seizures; p = 0.017).

Seizures are a clinically relevant comorbidity in ND, particularly in AD. Knowledge of the first clinical symptom in ND may allow for estimation of seizure risk.