Studies point to need for better scrutiny of first ever seizures
To PhD candidate Dr Emma Foster researching the human brain and its mysteries poses a fascinating intellectual challenge. To Dr Foster as a clinician, it means potentially seeing first-hand patients’ lives improved by new ways of managing devastating diseases.
Dr Foster, an Epilepsy Fellow working at the Department of Neurology, Alfred Hospital, is investigating ‘first ever’ seizures; unexpected and traumatic events that can lead to emotional and financial burden on those suffering them and their families.
“In my workload, I realised that we could do more for people with first seizures,” Dr Foster said. “We’ve realised that the way these seizures are managed is very variable.”
Around 14,000 people a year in Australia have first ever unprovoked seizures, she said.
These seizures affect all age groups but the very young and elderly people have the highest incidence. Between 30 and 40% of people who experience them will go on to be diagnosed with epilepsy while the majority will never have another seizure.
A diverse range of other conditions manifests as seizures. A small percentage of patients has acute seizures due to metabolic causes such as very low blood sugar or salt levels, acute toxic withdrawals from alcohol or recreational drugs, or due to prescribed drugs. First ever seizures can also be induced by acute brain injury, stroke or a brain bleed.
Diagnosing the cause of a first ever seizure rapidly is therefore vital. “If we miss something like a brain bleed, the seizure is the least of a patient’s problems that need to be addressed,” Dr Foster said.
Dr Foster is the first author on two recent papers on new onset seizures.
The first study, published in Neurological Clinical Practice, compared the aetiology, prognosis and management of adult patients presenting to Cabrini Malvern Hospital who had either had their first seizure in the community (97 patients) or in hospital (54). It found the community group, on average 10 years younger (80.5 years compared to 70 years), was more likely to be diagnosed with new onset epilepsy whereas the hospitalised patients were more likely to have seizures with acute symptoms unrelated to epilepsy. Despite this, about 72% of patients in each group were prescribed anti-epileptic drug (AED) therapy on discharge.
The study also found that the hospitalised patients were at increased risk of seizures due to a provoking factor such as a stroke, brain bleed or tumour and also by some proconvulsant medications, particularly tranexamic acid, which is used in cardiac surgery to help prevent blood clots. A more standardised approach to AED prescribing is needed, it found.
“The hospital cohort were sick people who were frail and vulnerable to seizures due to their underlying problems,” Dr Foster said. “As clinicians we have to be aware that what we prescribe could induce a seizure in these people and have to be quite mindful of what we do in hospital with an acute symptomatic seizure,” she said.
A review paper published in Epilepsy & Behavior scrutinising the international literature on the costs of first ever seizures found a dearth of data on the subject with the limited research available suggesting that the cost of first ever seizures is underestimated.
Establishing this cost was necessary in order to determine ways of optimally managing first ever seizures and to avoid preventable seizure recurrence, morbidity and mortality, and for health budget planning, the paper found.
“This needs to be explored, and defined much more carefully, to see if first interventions are effective,” Dr Foster said.
A few studies cited in the paper had found that first seizure clinics reported substantial reduction in the recurrence of seizures and the utilisation of resources, she said.
Dr Foster is now working on a three-year retrospective study of data about patients who attended one of four such clinics in Melbourne, including the Alfred Hospital’s First Seizure Clinic, in which Dr Foster works.
She is supervised by senior author Professor Patrick Kwan from the Central Clinical School's Department of Neuroscience.
Foster E, Holper S, Chen Z, Kwan P. Presentation and management of community-onset vs hospital-onset first seizures. Neurol Clin Pract. 2018 Oct;8(5):421-428. doi: 10.1212/CPJ.0000000000000524.
Foster E, Ademi Z, Lawn N, Chen Z, Carney P, Liew D, O'Brien TJ, Kwan P. Determining the cost of first-ever seizures: A narrative review and future directions. Epilepsy Behav. 2019 Jan;90:291-294. doi: 10.1016/j.yebeh.2018.10.045. Epub 2018 Nov 23.