Abstract
Objective: Psychosis of epilepsy (POE) occurs more frequently in temporal lobe epilepsy, raising the question as to whether abnormalities of the hippocampus are aetiologically important. Despite decades of investigation, it is unclear whether hippocampal volume is reduced in POE, perhaps due to small sample sizes and methodological limitations of past research. Methods: In this study, we examined the volume of the total hippocampus, and the hippocampal head, body and tail, in a large cohort of patients with POE and patients with epilepsy without psychosis (EC). One hundred adults participated: 50 with POE and 50 EC. Total and subregional hippocampal volumes were manually traced and compared between (1) POE and EC; (2) POE with temporal lobe epilepsy, extratemporal lobe epilepsy and generalised epilepsy; and (3) patients with POE with postictal psychosis (PIP) and interictal psychosis (IP). Results: Compared with EC the POE group had smaller total left hippocampus volume (13.5% decrease, p<0.001), and smaller left hippocampal body (13.3% decrease, p=0.002), and left (41.5% decrease, p<0.001) and right (36.4% decrease, p<0.001) hippocampal tail volumes. Hippocampal head volumes did not differ between groups. Conclusion: Posterior hippocampal volumes are bilaterally reduced in POE. Volume loss was observed on a posteroanterior gradient, with severe decreases in the tail and moderate volume decreases in the body, with no difference in the hippocampal head. Posterior hippocampal atrophy is evident to a similar degree in PIP and IP. Our findings converge with those reported for the paradigmatic psychotic disorder, schizophrenia, and suggest that posterior hippocampal atrophy may serve as a biomarker of the risk for psychosis, including in patients with epilepsy.
| Original language | English |
|---|---|
| Pages (from-to) | 688-694 |
| Number of pages | 7 |
| Journal | Journal of Neurology, Neurosurgery and Psychiatry |
| Volume | 90 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 16 May 2019 |
Keywords
- epilepsy
- hippocampus
- interictal psychosis
- postictal psychosis
- psychosis
Cite this
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Bilateral volume reduction in posterior hippocampus in psychosis of epilepsy. / Allebone, James; Kanaan, Richard; Maller, Jerome; O'Brien, Terry; Mullen, Saul Alator; Cook, Mark; Adams, Sophia J.; Vogrin, Simon; Vaughan, David N.; Connelly, Alan; Kwan, Patrick; Berkovic, S. F.; D'Souza, Wendyl J.; Jackson, Graeme; Velakoulis, Dennis; Wilson, Sarah J.
In: Journal of Neurology, Neurosurgery and Psychiatry, Vol. 90, No. 6, 16.05.2019, p. 688-694.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Bilateral volume reduction in posterior hippocampus in psychosis of epilepsy
AU - Allebone, James
AU - Kanaan, Richard
AU - Maller, Jerome
AU - O'Brien, Terry
AU - Mullen, Saul Alator
AU - Cook, Mark
AU - Adams, Sophia J.
AU - Vogrin, Simon
AU - Vaughan, David N.
AU - Connelly, Alan
AU - Kwan, Patrick
AU - Berkovic, S. F.
AU - D'Souza, Wendyl J.
AU - Jackson, Graeme
AU - Velakoulis, Dennis
AU - Wilson, Sarah J.
PY - 2019/5/16
Y1 - 2019/5/16
N2 - Objective: Psychosis of epilepsy (POE) occurs more frequently in temporal lobe epilepsy, raising the question as to whether abnormalities of the hippocampus are aetiologically important. Despite decades of investigation, it is unclear whether hippocampal volume is reduced in POE, perhaps due to small sample sizes and methodological limitations of past research. Methods: In this study, we examined the volume of the total hippocampus, and the hippocampal head, body and tail, in a large cohort of patients with POE and patients with epilepsy without psychosis (EC). One hundred adults participated: 50 with POE and 50 EC. Total and subregional hippocampal volumes were manually traced and compared between (1) POE and EC; (2) POE with temporal lobe epilepsy, extratemporal lobe epilepsy and generalised epilepsy; and (3) patients with POE with postictal psychosis (PIP) and interictal psychosis (IP). Results: Compared with EC the POE group had smaller total left hippocampus volume (13.5% decrease, p<0.001), and smaller left hippocampal body (13.3% decrease, p=0.002), and left (41.5% decrease, p<0.001) and right (36.4% decrease, p<0.001) hippocampal tail volumes. Hippocampal head volumes did not differ between groups. Conclusion: Posterior hippocampal volumes are bilaterally reduced in POE. Volume loss was observed on a posteroanterior gradient, with severe decreases in the tail and moderate volume decreases in the body, with no difference in the hippocampal head. Posterior hippocampal atrophy is evident to a similar degree in PIP and IP. Our findings converge with those reported for the paradigmatic psychotic disorder, schizophrenia, and suggest that posterior hippocampal atrophy may serve as a biomarker of the risk for psychosis, including in patients with epilepsy.
AB - Objective: Psychosis of epilepsy (POE) occurs more frequently in temporal lobe epilepsy, raising the question as to whether abnormalities of the hippocampus are aetiologically important. Despite decades of investigation, it is unclear whether hippocampal volume is reduced in POE, perhaps due to small sample sizes and methodological limitations of past research. Methods: In this study, we examined the volume of the total hippocampus, and the hippocampal head, body and tail, in a large cohort of patients with POE and patients with epilepsy without psychosis (EC). One hundred adults participated: 50 with POE and 50 EC. Total and subregional hippocampal volumes were manually traced and compared between (1) POE and EC; (2) POE with temporal lobe epilepsy, extratemporal lobe epilepsy and generalised epilepsy; and (3) patients with POE with postictal psychosis (PIP) and interictal psychosis (IP). Results: Compared with EC the POE group had smaller total left hippocampus volume (13.5% decrease, p<0.001), and smaller left hippocampal body (13.3% decrease, p=0.002), and left (41.5% decrease, p<0.001) and right (36.4% decrease, p<0.001) hippocampal tail volumes. Hippocampal head volumes did not differ between groups. Conclusion: Posterior hippocampal volumes are bilaterally reduced in POE. Volume loss was observed on a posteroanterior gradient, with severe decreases in the tail and moderate volume decreases in the body, with no difference in the hippocampal head. Posterior hippocampal atrophy is evident to a similar degree in PIP and IP. Our findings converge with those reported for the paradigmatic psychotic disorder, schizophrenia, and suggest that posterior hippocampal atrophy may serve as a biomarker of the risk for psychosis, including in patients with epilepsy.
KW - epilepsy
KW - hippocampus
KW - interictal psychosis
KW - postictal psychosis
KW - psychosis
UR - http://www.scopus.com/inward/record.url?scp=85062082657&partnerID=8YFLogxK
U2 - 10.1136/jnnp-2018-319396
DO - 10.1136/jnnp-2018-319396
M3 - Article
VL - 90
SP - 688
EP - 694
JO - Journal of Neurology, Neurosurgery and Psychiatry
JF - Journal of Neurology, Neurosurgery and Psychiatry
SN - 0022-3050
IS - 6
ER -