Neurodegenerative diseases and lifetime seizure risk: A study of autopsy proven cases

Abstract

AbstractBackgroundIn the neurodegenerative conditions Alzheimer disease (AD), Lewy body disease (LBD) including the neuropathologically indistinguishable Parkinson disease and dementia with Lewy bodies, frontotemporal lobar degeneration (FTLD), corticobasal degeneration (CBD), progressive supranuclear palsy (PSP) and multiple system atrophy (MSA) figures for seizure risk are inconsistent, rare or lacking. This is particular true if neuropathologically confirmed diagnoses are stipulated. Therefore, our goal was to determine the lifetime risk for epileptic seizures and to investigate associated clinical parameters in neuropathologically diagnosed neurodegenerative diseases.MethodCases from the Neurobiobank Munich, Germany, were matched with information from clinical files regarding the occurrence of epileptic seizures. The aforementioned diseases were compared for lifetime seizure risk. The predictive value of the first clinical symptom regarding lifetime risk for seizures was analyzed and associations between the occurrence of seizures and survival was investigated.ResultWe analyzed 454 neuropathologically diagnosed cases with sufficient clinical data available. 144 had AD, 103 LBD, 93 PSP, 53 FTLD, 36 MSA, and 25 CBD. Lifetime risk for epileptic seizures was 31.3% in AD, 20.0% in CBD, 12.6% in LBD, 11.3% in FTLD, 8.3% in MSA and 7.5% in PSP. Patients with AD had a statistically significantly higher lifetime risk for seizures compared to patients with FTLD (p=0.005), LBD (p=0.001), MSA (p=0.005) and PSP (p<0.001). An increased lifetime seizure risk was found in patients with cognitive first symptoms when compared to those with non‐cognitive first symptoms (21.1% vs. 11.0%). A decreases lifetime risk for seizures was observed in cases with motor first symptoms when compared to those with non‐motor first symptoms (10.3% vs. 20.5%). MSA patients with seizures survived longer when compared to those without (12.3 vs. 7.0 years; p = 0.017).ConclusionIn this clinical neuropathological correlation study, nearly every third AD patient and approximately every fifth patient with a neurodegenerative disease experienced epileptic seizures in the disease course. Therefore, epileptic seizures are an important comorbidity in neurodegenerative conditions, in particular in AD. Assessment of the first clinical symptom may improve early estimation of the lifetime seizure risk in the studied neurodegenerative diseases.