Neuropsychiatric Symptoms of Epilepsy

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relatively frequent – with an estimated rate of misdiagnosis of 32–38 %. Reasons
for high misdiagnosis rates include misinterpretation of behavioral, physiological,
syndrome- related and medication-related events by parents, paid support workers,
and healthcare professionals [ 14 ]. There can often be diagnostic overlap and overshadowing,
for instance the presence of stereotyped and self-stimulatory behaviors,
expressions of pain or frustration and periods of drowsiness or withdrawal of
engagement with the environment have all been misdiagnosed as seizures in people
with a learning disability. Therefore, in England, National Institute for Clinical
Excellence (NICE) clinical guidelines state that diagnosis of epilepsy should be
established by a specialist medical practitioner with training and expertise in epilepsy.
They further advise that diagnosis should be based upon a detailed history
and (where possible) eyewitness reports of events usually supplemented with
EEG. Where diagnosis cannot be clearly established, further investigations (e.g.,
blood tests, sleep EEG, neuroimaging, and 12-lead ECG) and/or referral to a tertiary
center is recommended.
How Is Epilepsy Manifest in LD?
Compared to epilepsy in the general population, epilepsy in people with an LD is
more likely to be refractory to antiepileptic drug (AED) treatment, with prognosis
for seizure control in people with learning disability and epilepsy poorer than for
those with epilepsy without learning disability [ 15 ]. These higher rates of inadequately
controlled epilepsy bring increased rates of morbidity and also mortality
[ 16 ]. In a Swedish study of over 1400 patients with learning disability, followed up
for 7 years, the standardized mortality ratio (SMR) for those with learning disability
without epilepsy was 1.6 but the SMR increased to 5.0 in those with concomitant
epilepsy [ 17 ]. As is also the case for those with epilepsy in the absence of an associated
learning disability, it is among those with ongoing seizures that the risk of
neuropsychiatric symptoms is greatest.
How Is Psychopathology Diagnosed in People with LD?
There are particular and very important challenges to consider when diagnosing
neuropsychiatric symptoms in people with a significant learning disability.
People with more severe learning disabilities often lack the language abilities to
verbally describe their psychological experiences. In these circumstances history taking
should focus on asking carers about observable changes in presentation that may
be signs of the development of psychopathology. For instance, possible biological
features of depression such as sleep disturbance and change in appetite should be
discussed with carers. Behavioral changes such as decreased social interaction, loss of
interest in activities previously engaged in, apparent agitation or distress, tearfulness,