Journal Article Annotations
2018, 1st Quarter

Neuropsychiatry

Annotations by AUTHOR1 and AUTHOR2
April 2018

Seizure activity and individual vulnerability on first-episode interictal psychosis in epilepsy
The expanding prominence of toxic leukoencephalopathy

PUBLICATION #1 — Neuropsychiatry

Seizure activity and individual vulnerability on first-episode interictal psychosis in epilepsy

Adachi N, Akanuma N, Fenwick P, et al

Abstract: Epilepsy Behav 2018; 79:234-238

Objective: Despite a theoretical consensus that interictal psychosis (IIP) is related to various epilepsy-related factors, the impact of seizure activity on development of IIP remains inconclusive. This is the first controlled study using quantitative seizure-activity measures at the onset of IIP.

Methods: One hundred and eighty-one patients with epilepsy who exhibited first-episode IIP (IIP group) and 427 patients with epilepsy without psychotic episodes (control group) were enrolled. The control group was matched for age, epilepsy type, and duration of epilepsy. The two seizure-activity indices (seizure frequency at the time of onset of first-episode IIP and the number of seizures before the onset of IIP) were evaluated and compared between the IIP and control groups. Logistic regression analysis was used for extracting risk variables to develop first-episode IIP.

Results: The sum of previous seizures was greater in the IIP than in control groups. This was particularly the case in the patients with partial epilepsies (PE). Higher seizure frequency in the patients with PE was associated with the development of first-episode IIP while no association was found in the whole cohort or in the patients with generalized epilepsies (GE). Subsequent multivariate analysis revealed the sum of previous seizures and family history of psychosis as risk variables to first-episode IIP.

Conclusions: The accumulation of seizure-related damages and family history of psychosis is associated with the onset of IIP episodes, particularly in the patients with PE. Seizure activity and individual vulnerability to psychosis are likely to be interacted for as the development of IIP in patients with epilepsy.

On PubMed: Epilepsy Behav 2018; 79:234-238

Annotation

Type of study: Cohort study

The finding: Greater total number of prior seizures (possibly skewed towards complex partial seizures) and presence of a family history of psychosis are significant predisposing factors for interictal psychosis. Also, mesial temporal sclerosis was a significant predisposing factor, although partial vs generalized seizure type was not.

Strength and weaknesses: A major and underemphasized aspect of this study was surprising access to seizure frequency/number data in a large number of patients (e.g. through seizure diaries), collected from the point of epilepsy diagnosis as far back as the 1980s. The introduction suggests that this study might contribute to settling the debate between whether increased or decreased seizure frequency (via accumulated damage vs, for example, forced normalization). Due to some confusing and internally inconsistent language, though, this is not completely clear since seizure frequency immediately preceding interictal psychosis onset seems not to have been studied. This may be excusable since this time window of epilepsy-psychosis is thought to be more relevant to post-ictal than interictal psychosis, but the lack of clarity remains.

Relevance: Barring the presence of a very psychiatrically-savvy neurologist, inter- and post-ictal psychopathology might only be detected by a CL psychiatrist. Any information that helps raise and hone awareness to these syndromes is important, and a high quality study like this one is optimal.

PUBLICATION #2 — Neuropsychiatry

The expanding prominence of toxic leukoencephalopathy

Filley CM, McConnell BV, Anderson CA

Abstract: J Neuropsychiatry Clin Neurosci 2017; 29(4):308-318

Toxic leukoencephalopathy (TL) is a disorder of brain white matter caused by exposure to leukotoxic agents. Magnetic resonance imaging (MRI) can readily identify this syndrome, and, together with diffusion tensor imaging, MRI continues to offer important insights into its nature. Since the first formal description of TL in 2001, many new leukotoxic disorders have been recognized, and the range of leukotoxins has expanded to include more therapeutic drugs, drugs of abuse, and environmental insults. While the understanding of pathophysiology remains incomplete, TL is increasingly common in clinical practice, and the potential long-term cognitive sequelae of toxic white matter injury merit attention.

On PubMed: J Neuropsychiatry Clin Neurosci 2017; 29(4):308-318

Annotation

Type of study: Systematic review

The finding: The number of substances and the range of leukoencephalopathies appears to be wider than most might think.

Strength and weaknesses: This is a comprehensive review from a lead author who happens to be one of the world’s leading experts in white matter disease. It’s strength may also be a weakness, however, since it is not targeted at any one particular toxic leukoencephalopathy; the causes and consequences are both diverse.

Relevance: With heroin, morphine, and fentanyl appearing prominently on the list of offenders, and hospitalizations of misusers of these drugs on the rise, consultation-liaison psychiatrists are more often called upon to see patients with not just overdoses, but also “mysteriously” prolonged “intoxication.” This article will be a go-to piece for some time for self-education and for getting trainees started on presentations on this topic. It’s a PDF to have readily at hand.