INSPIRE Studentship Report

Transcription

1 INSPIRE Studentship Report 'He was thinking, incidentally, that there was a moment or two in his epileptic condition almost before the fit itself (if it occurred in waking hours) when suddenly amid the sadness, spiritual darkness and depression, his brain seemed to catch fire at brief moments...his sensation of being alive and his awareness increased tenfold at those moments which flashed by like lightning. His mind and heart were flooded by a dazzling light. All his agitation, doubts and worries, seemed composed in a twinkling, culminating in a great calm, full of understanding...but these moments, these glimmerings were still but a premonition of that final second (never more than a second) with which the seizure itself began. That second was, of course, unbearable.' Excerpt from The Idiot by Fyodor Dostoevsky Application Process I have been interested in neurological disorders for a long time now and this project has given me the opportunity to familiarise myself with a more specialised area within this field, epilepsy, and more specifically Transient Epileptic Amnesia (TEA). The main feature of TEA is a brief period of memory loss whose underlying cause is thought to be malfunctions in the temporal lobes which are caused by epilepsy. Everything began with the taster day, which gave me insight into what research of various neurological conditions might be like. This increased my fascination with the subject and I applied for the Inspire Studentship. I also started reading various articles and scientific studies in order to broaden my knowledge of TEA. With the help and guidance of Professor Adam Zeman I compiled the grant application and was fortunate enough to be chosen by the committee. TEA One aspect that I found particularly interesting about TEA was its connections with some of my other areas of interest within the psychiatric field. Research in epilepsy shows that adverse life events and mood disorders are positively correlated with an increased incidence of epileptic episodes. They have a complex 1

2 relationship with epilepsy: comorbidities can exacerbate epilepsy or each other, and vice versa. For example, depression and anxiety disorders are the most common psychiatric comorbidities in patients suffering from epilepsy. There is not a lot of research in the field of TEA, but I was able to access the largest existing database of TEA patients in the world (N=120), which was established by the TIME (The Impairment of Memory in Epilepsy) team. The TIME Project began work in 2003 as a nationwide investigation of TEA. This is a form of epilepsy giving rise to short periods of amnesia, commonly associated with other persistent memory problems. The disorder is often misdiagnosed, as it is an unfamiliar form of epilepsy, but it responds well to treatment. It therefore has clinical importance. It also has theoretical significance as the associated memory problems pose challenges to theories of memory. My Project The question which my project aimed to answer is whether life events and mood disorders are linked with TEA. I looked for life events around 5 main areas: early life, relationships, work life, family life, and leisure. Apart from early life, I gathered life events at two time points: pre-onset of TEA (roughly 12 months), as well as in the distant past. I planned to use SPSS and run a within participants ANOVA on the data I collected. I planned to investigate whether there were any correlations between the number of events in these categories in the patient s life. However, using just the number of incidents was a limitation, as the severity of the events should also have been taken into account. Moreover not having a control group is perhaps the biggest limitation of my project, as I couldn t compare patients with TEA with patients without. Therefore, the inferences that can be drawn from the data I collected are limited. Following Professor Zeman s suggestions I also looked for indicators of emotional lability. This is has been noted in several studies on TEA and is described as emotional vulnerability, characterised by overreactions to even minor provocations, adverse events and disappointments ( when listening to music or watching military parades ). The Steps In order to collect the data from the TIME series I went to St. Luke s Campus to access the patient files and form a database. The typical file had elaborate information about the patient s epilepsy rather than facts regarding life events 2

3 or mood disorders. All of them described in detail the amnestic attack with details suggesting the diagnosis of TEA. Example of a patient account: A 63 year old engineer had experienced about 20 episodes of transient amnesia lasting for around one hour each over the past three years. Most had occurred on waking. He would characteristically say I m not sure where I am at the onset; his conversation would then disclose a retrograde amnesia extending back for about 10 years. He has no recall for events during the attacks. In other respects, he converses and behaves normally during attacks. Over the year before presenting to us he had complained to his wife of a strange smell or taste which he noticed at the onset of attacks. He had been knocked out by a fly press in MRI and wake and sleep EEG were normal. Treatment with carbamazepine abolished the attacks. Retrieved from Zeman, Boniface & Hodges (1998) This account is very relevant as it suggests many of the classic symptoms of TEA such as amnesia on awakening, episodes lasting for 20 to 60 minutes, olfactory hallucinations or strange smell or taste and repetitively asking the same question, such as What are we supposed to be doing today or, as in this case, statements similar to I m not sure where I am. In addition to the hospital and patient notes I looked at different questionnaires and tests putting special emphasis on the HADS (Hospital Anxiety and Depression Scale), which is used to determine the level of anxiety and depression a patient is feeling. By doing this I was able to point out which patients were suffering from these types of conditions and to insert them in my database accordingly. Out of the recorded cases of patients with TEA, 21 of them suffered from depressive episodes of varying severity where they reported low mood, loss of energy, lack of pleasure and sleep disturbances, among other symptoms. When analysing patient data another factor that I looked for was anxiety. In 30 cases anxiety was reported. This included symptoms of nervousness, a sense of panic, not being able to relax etc. Another factor which was relevant to my study was stress. Around 20 patients said they were stressed or going through a stressful time around the period of their amnestic attacks. Perhaps this can be explored further by enabling doctors to enquire further information about different life stressors in the patient s life. Fifteen of the depressed patients also had clinically significant levels of anxiety. While it is not uncommon for depression and anxiety to be comorbid, 75% is a 3

4 higher than usual proportion. However, it is possible that this large percentage is due to the small number of participants so perhaps the analysis of a larger number of patients might indicate whether comorbid depression and anxiety is particularly common in patients with TEA. Findings Biographical information about the patients was limited so, unfortunately, the data on life events is quite sparse. However, most records had notes about past head injuries or physical traumas. Family History sister with cancer mother with Alzheimer s Disease and Schizophrenia auto-immune thyroid disease younger sister with depression sister with epilepsy daughter with epilepsy father with depression cousin with epilepsy daughter with anorexia and depression parents with dementia Emotional Lability Fifteen patients disclosed being more emotionally reactive than normal. Most life events were not recorded, but some patients had had adverse events in: early life spontaneous subdural haematoma multiple concussions migraines with aura car accident difficult family events premature birth meningitis being fostered relationships and family life death of close friend death of husband 4

5 death of sister only sister diagnosed with cancer worries of son s marriage end of relationship work life being made redundant stressful or difficult job worked abroad leisure no relevant information found in this category Other notable symptoms Derealisation: the world is not as vibrant and connected as it should be. It feels like I m acting in a play, living on another planet Remembering not being able to remember Also interesting to note is that some patients characteristically experienced amnestic episodes while on holiday Notes for further studies As previously stated, the data gathered does not allow for strong inferences to be made, even regarding correlational links. One aspect that stood out was the high rate of comorbid depression and anxiety, and this is something that should be investigated further, perhaps on a larger sample. The information gathered suggests that at least some of the patients had experienced adverse life events. While the case can be made that everyone suffers from negative events at some point in their lives, it appears that negative events in early life were particularly common. However, it is not clear whether this is indeed the case, as most of the patient files did not provide detailed biographical accounts. In the future it might prove useful to have more information about critical events in the patient s life, in addition to the usual medical history. Due to incomplete data, it was not feasible to perform an ANOVA, but with more complete data a statistical analysis might provide relevant information about possible correlations. Lastly, the absence of a control group makes it difficult to draw any meaningful conclusions. Future studies might benefit not only from having a larger sample, but also from 5

6 having a control group with an equivalent number of participants. This would make any statistical findings much more reliable. Acknowledgments I would like to thank the University of Exeter for allocating me the Inspire Studentship, without your financial help many students would not have the possibility to benefit from such an incredible research opportunity. I would also like to thank Professor Adam Zeman for his continued support and guidance throughout the project. Lastly, I would like to thank Dr Sharon Savage and Dr John Baker for their help. References Zeman, A. Z. J., Boniface, S. J., & Hodges, J. R. (1998). Transient epileptic amnesia: a description of the clinical and neuropsychological features in 10 cases and a review of the literature. Journal of Neurology, Neurosurgery & Psychiatry, 64(4), doi: /jnnp