Temporal lobe epilepsy and depression: a dysfunctional lobe overshadows a sclerotic hippocampus.
TL;DR
The study shows that presence of depression in drug-resistant patients with mesial temporal lobe epilepsy is linked to hippocampal disfunction rather than neuronal density in the hippocampus.
Abstract
Depression is one of the most frequent psychiatric comorbidities in drug-resistant patients with epilepsy, reaching up to 60% of them. Studies indicate that the pathophysiology of depression and epilepsy have a lot in common, especially the temporal lobe epilepsy (TLE). Since hippocampal sclerosis (HS) is a frequent histopathology finding in patients with TLE, the purpose of this study was to investigate if there is a frequency relation between depression and the different types of HS. 119 patients with TLE, with and without HS, were selected (HS1 = 40, HS2 = 40, NHS = 39) and their medical records were analyzed. Depression was seen in 44 of them, without difference between HS types nor NHS (HS1 = 20, HS2 = 12, NHS = 12, p = 0.1). However, women were 3 times more likely to have depression (p = 0.004). Patients without HS were younger at seizure onset than those with HS2 (p = 0.02). The HS2 group had more cases of initial precipitating injury than NHS (p < 0.001) but were similar to HS1 patients. Our study shows that presence of depression in drug-resistant patients with mesial temporal lobe epilepsy is linked to hippocampal disfunction rather than neuronal density in the hippocampus.