Publicação
Mental disorders and refractory epilepsy : evidence of a bidirectional relationship
| Resumo: | Introduction: Although the relationship between mental disorders and epilepsy has been studied for several years there is a lack of systematization of knowledge in this area. People with epilepsy, particularly those who are refractory to pharmacological treatment, have a high prevalence of psychiatric comorbidities. For these patients, surgical treatment is often proposed; its effects at a psychopathological level may depend on the clinical characteristics of each person and the surgical technique itself. While some epilepsy-related characteristics may contribute to a higher risk of psychiatric disorders, these may also be associated with the prognosis of refractory epilepsy. Aims: This study focused on the relationship between mental illness and refractory epilepsy. Specifically, our objectives were to study the mutual influence between refractory epilepsy or epilepsy surgery and mental disorders. Moreover, we also aimed to determine if the dysfunction, associated with the epilepsy origin, of a particular lobe or hemisphere influenced the risk or the type of any psychiatric disorder. Methods: To investigate these questions, we designed one cross-sectional and five ambispective cohort studies, using a sample of people with refractory epilepsy referred to surgery. The participants were accessed before surgery and annually, after that, during a maximum period of three years, by a psychiatrist from the Epilepsy Surgery Group of Hospital de Santa Maria. Assessments included a clinical evaluation and a battery of scales and questionnaires. Different statistical approaches were used according to the aim of each study. Results: Our results showed that 46% of people with refractory epilepsy had a lifetime history of some psychiatric disorder and the risk seems to be higher in those with an epilepsy originated in the right hemisphere. Regarding personality, 70% had a dysfunctional personality pattern. After epilepsy surgery, this percentage dropped to 58% and the difference was found to be significant. “Avoidant” and “Compulsive” personality patterns were associated with a temporal epilepsy origin while an extratemporal origin was associated with “Histrionic” and “Antisocial” patterns. Additionally, our studies allowed us to identify that epilepsy with a multilobar origin and a neuromodulation technique, the Deep Brain Stimulation of the Anterior Thalamic Nucleus (ANT-DBS) were associated with the development of de novo psychiatric disorders. It was also demonstrated that in people with a bilateral epilepsy origin, no remission of epileptic seizures and in those submitted to ANT-DBS there was an increase of psychopathological scores and, consequently, a greater mental suffering, one year after the epilepsy surgery. Regarding the course of refractory epilepsy, we showed that a history of any mental illness is a predictor of lower seizure control after surgery. In fact, regarding epilepsy surgery outcome this was the most important contributor to the accuracy of a predictive model. Conclusions: Important conclusions can be drawn from these results. People with refractory epilepsy have high rates of mental disorders and dysfunctional personality adjustment patterns. Regarding the relationship with surgery, people who are subjected to ANT-DBS appear to have an increased probability of either developing new psychiatric syndromes or worsening previous psychopathological symptoms, when compared to conventional resective surgery. Despite the fact that this modality of neuromodulation is relatively recent, this work points to a high risk of psychiatric effects. Moreover, people with a bilateral or multilobar epilepsy origin also have higher risk of worsening or developing de novo psychopathology. Considering these data and our findings regarding the poor reduction after surgery of those with psychiatric disorders present, we hypothesize that there might be a subgroup of people with wider brain dysfunction, leading to a more serious neuropsychiatric disorder and therefore worse global prognosis. In summary, together these studies allowed us to demonstrate evidence for a bidirectional relationship between refractory epilepsy and mental disorders. Epilepsy-related factors affect the course of mental disorders and mental disorders affect the course of epilepsy after surgery. Similarly, we showed that epilepsy surgery also affects the future course of psychopathological symptoms and dysfunctional behavioural patterns. By demonstrating this relationship, our work emphasized the importance of a close collaboration between neurologists and psychiatrists in the follow-up of people with refractory epilepsy. Moreover, we showed that the potential dysfunction of a particular zone of the brain, due to the epilepsy origin, may be associated with a higher risk for any mental disorder and an increased probability of developing certain dysfunctional personality characteristics. These findings may add to the investigation of the biological basis of mental illnesses. Future studies should use bigger samples to confirm our results regarding the psychopathological risks of epilepsy surgery, particularly, ANT-DBS, and explore the hypothesis of a subgroup of patients with a more generalized brain dysfunction and what are the neurobiological mechanisms involved in this dysfunction. |
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| Autores principais: | Cruz, Filipa Andreia Lemos Novais Oliveira |
| Assunto: | Epilepsia refratária Doença mental Cirurgia da epilepsia Teses de doutoramento - 2020 |
| Ano: | 2020 |
| País: | Portugal |
| Tipo de documento: | tese de doutoramento |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório da Universidade de Lisboa |
| Resumo: | Introduction: Although the relationship between mental disorders and epilepsy has been studied for several years there is a lack of systematization of knowledge in this area. People with epilepsy, particularly those who are refractory to pharmacological treatment, have a high prevalence of psychiatric comorbidities. For these patients, surgical treatment is often proposed; its effects at a psychopathological level may depend on the clinical characteristics of each person and the surgical technique itself. While some epilepsy-related characteristics may contribute to a higher risk of psychiatric disorders, these may also be associated with the prognosis of refractory epilepsy. Aims: This study focused on the relationship between mental illness and refractory epilepsy. Specifically, our objectives were to study the mutual influence between refractory epilepsy or epilepsy surgery and mental disorders. Moreover, we also aimed to determine if the dysfunction, associated with the epilepsy origin, of a particular lobe or hemisphere influenced the risk or the type of any psychiatric disorder. Methods: To investigate these questions, we designed one cross-sectional and five ambispective cohort studies, using a sample of people with refractory epilepsy referred to surgery. The participants were accessed before surgery and annually, after that, during a maximum period of three years, by a psychiatrist from the Epilepsy Surgery Group of Hospital de Santa Maria. Assessments included a clinical evaluation and a battery of scales and questionnaires. Different statistical approaches were used according to the aim of each study. Results: Our results showed that 46% of people with refractory epilepsy had a lifetime history of some psychiatric disorder and the risk seems to be higher in those with an epilepsy originated in the right hemisphere. Regarding personality, 70% had a dysfunctional personality pattern. After epilepsy surgery, this percentage dropped to 58% and the difference was found to be significant. “Avoidant” and “Compulsive” personality patterns were associated with a temporal epilepsy origin while an extratemporal origin was associated with “Histrionic” and “Antisocial” patterns. Additionally, our studies allowed us to identify that epilepsy with a multilobar origin and a neuromodulation technique, the Deep Brain Stimulation of the Anterior Thalamic Nucleus (ANT-DBS) were associated with the development of de novo psychiatric disorders. It was also demonstrated that in people with a bilateral epilepsy origin, no remission of epileptic seizures and in those submitted to ANT-DBS there was an increase of psychopathological scores and, consequently, a greater mental suffering, one year after the epilepsy surgery. Regarding the course of refractory epilepsy, we showed that a history of any mental illness is a predictor of lower seizure control after surgery. In fact, regarding epilepsy surgery outcome this was the most important contributor to the accuracy of a predictive model. Conclusions: Important conclusions can be drawn from these results. People with refractory epilepsy have high rates of mental disorders and dysfunctional personality adjustment patterns. Regarding the relationship with surgery, people who are subjected to ANT-DBS appear to have an increased probability of either developing new psychiatric syndromes or worsening previous psychopathological symptoms, when compared to conventional resective surgery. Despite the fact that this modality of neuromodulation is relatively recent, this work points to a high risk of psychiatric effects. Moreover, people with a bilateral or multilobar epilepsy origin also have higher risk of worsening or developing de novo psychopathology. Considering these data and our findings regarding the poor reduction after surgery of those with psychiatric disorders present, we hypothesize that there might be a subgroup of people with wider brain dysfunction, leading to a more serious neuropsychiatric disorder and therefore worse global prognosis. In summary, together these studies allowed us to demonstrate evidence for a bidirectional relationship between refractory epilepsy and mental disorders. Epilepsy-related factors affect the course of mental disorders and mental disorders affect the course of epilepsy after surgery. Similarly, we showed that epilepsy surgery also affects the future course of psychopathological symptoms and dysfunctional behavioural patterns. By demonstrating this relationship, our work emphasized the importance of a close collaboration between neurologists and psychiatrists in the follow-up of people with refractory epilepsy. Moreover, we showed that the potential dysfunction of a particular zone of the brain, due to the epilepsy origin, may be associated with a higher risk for any mental disorder and an increased probability of developing certain dysfunctional personality characteristics. These findings may add to the investigation of the biological basis of mental illnesses. Future studies should use bigger samples to confirm our results regarding the psychopathological risks of epilepsy surgery, particularly, ANT-DBS, and explore the hypothesis of a subgroup of patients with a more generalized brain dysfunction and what are the neurobiological mechanisms involved in this dysfunction. |
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