The Comorbidities of Epilepsy

Marco Mula

• Publisher: Academic Press
• Year: 2019
• Print ISBN: 9780128186206
• eBook ISBN: 9780128148785
• Topic: Medicine
• Subtopic: Neurology

Epilepsy is one of most frequent neurological disorders affecting about 50 million people worldwide and 50% of them have at least another medical problem in comorbidity; sometimes this is a the cause of the epilepsy itself or it is due to shared neurobiological links between epilepsy and other medical conditions; other times it is a long-term consequence of the antiepileptic drug treatment.The Comorbidities of Epilepsy offers an up-to-date, comprehensive overview of all comorbidities of epilepsy (somatic, neurological and behavioral), by international authorities in the field of clinical epileptology, with an emphasis on epidemiology, pathophysiology, diagnosis and management. This book includes also a critical appraisal of the methodological aspects and limitations of current research on this field. Pharmacological issues in the management of comorbidities are discussed, providing information on drug dosages, side effects and interactions, in order to enable the reader to manage these patients safely.The Comorbidities of Epilepsy is aimed at all health professionals dealing with people with epilepsy including neurologists, epileptologists, psychiatrists, clinical psychologists, epilepsy specialist nurses and clinical researchers.- Provides a comprehensive overview of somatic, neurological and behavioral co-morbidities of epilepsy- Discusses up-to-date management of comorbidities of epilepsy- Written by a group of international experts in the field

Chapter 1

The comorbidities of epilepsy: A conceptual framework

Daniel Navin Olschewski⁎; Prisca R. Bauer^†; Josemir W. Sander^{‡,§,¶ ⁎} Department of Neurology, University Hospital of Cologne, Cologne, Germany
^† Lyon Neuroscience Research Center, Brain Dynamics and Cognition Team, INSERM UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
^‡ NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London, United Kingdom
^§ Chalfont Centre for Epilepsy, Chalfont St Peter, United Kingdom
^¶ Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands

Abstract

Over 50% of people with epilepsy have one or more somatic or psychiatric conditions. Five mechanisms of association are identified: conditions that cause epilepsy (causative); conditions caused by epilepsy (resultant); conditions that share the same risk factors as epilepsy, conditions that link epilepsy and other conditions; conditions that can be caused by epilepsy and vice versa (bidirectional); and lastly, artifactual associations between epilepsy and other conditions. Comorbidities have consequences for the diagnosis and prognosis of epilepsy and negatively impact quality of life and health care-related costs. Epilepsy is thus not a stand-alone condition but a symptom of systemic dysfunction requiring appropriate diagnosis and treatment of all associated symptoms and conditions.

Keywords

Epilepsy; Co-morbidity; Risk factor; Genetics; Inflammation; Oxidative stress; Mitochondrial dysfunction; Glycation; Methylation

Contents

• 1. Mechanisms of association between epilepsy and comorbid conditions
  • 1.1 Causative
  • 1.2 Resultant
  • 1.3 Shared risk
  • 1.4 Genetics
  • 1.5 Bidirectional
  • 1.6 Chance, artifactual, or spurious association
• 2. The burden of comorbidity
  • 2.1 Diagnosis
  • 2.2 Treatment
  • 2.3 Quality of life
  • 2.4 Mortality
  • 2.5 Costs
• 3. Epilepsy as a systemic condition
• References

Abbreviations

AED’s antiepileptic drugs

ICD International Classification of Diseases

ILAE International League Against Epilepsy

QOLIE-10 quality of life in epilepsy questionnaire

SCN1A gene that codes for the alpha subunit of the voltage-gated sodium ion channel

SUDEP sudden unexpected death in epilepsy

Epilepsy, a relatively common neurological condition, is a complex symptom that rarely stands alone. Several large population-based studies have shown that up to 50% of people with epilepsy also have a comorbid condition [1, 2]. In epilepsy, comorbidity implies the coexistence of other medical conditions preceding, co-occurring with, or following the diagnosis of epilepsy, related or unrelated to the underlying potential or putative cause of epilepsy.

The comorbidities of epilepsy encompass somatic and psychiatric conditions, and the prevalence of some of them is up to eight times higher in people with epilepsy than in the general population [3–5]. The comorbidities may impact the diagnosis of epilepsy mainly due to issues of attributions. They can influence treatment decisions as often the choice of antiepileptic medications may positively or negatively affect the comorbid condition, thus complicating a holistic approach to the management of the individual. Comorbidities also affect quality of life and prognosis and result in more frequent visits to health professionals and higher health care-related costs [6].

This chapter provides a theoretical framework for the comorbid associations of epilepsy. It should be seen as a foreword for this topical book on the comorbidities associated with epilepsy, which are responsible for a significant part of the burden epilepsy imposes on the individual and society. It also provides a brief overview of the different potential mechanisms of association between epilepsy and comorbidities and of some recent pathophysiological evidence, which may explain some associations. Most of the comorbid associations of epilepsy mentioned in this chapter will be discussed in more detail in other chapters.

1 Mechanisms of association between epilepsy and comorbid conditions

The comorbidities associated with epilepsy can be subdivided by affected organ system and the International Classification of Diseases [4, 5]. Based on the current understanding of disease mechanisms and temporal associations, epilepsy-associated comorbid conditions can also be divided into five mechanist categories. This type of categorization was initially conceptualized for the classification of migraine and associated comorbid disorders [7]. The categories are: causative mechanisms; resultant mechanisms; shared risk factors; bidirectional effects; and chance and artifactual comorbidities [4, 5]. Table 1 summarizes conditions associated with epilepsy.

Table 1

Mechanisms of association between epilepsy and other conditions

Mechanisms of association	Conditions	Pathophysiological link (reference)
Causative	Direct
	Brain tumors (primary, secondary)	Direct cause-and-effect relationship [8]
	Cerebrovascular disease	Direct cause-and-effect relationship [9]
	Alcohol dependence	Changes in brain function/reduction of seizure threshold ...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributors
• Foreword
• Preface
• Chapter 1: The comorbidities of epilepsy: A conceptual framework
• Chapter 2: Costs of epilepsy: The impact of comorbidities
• Chapter 3: Bone health in epilepsy
• Chapter 4: Epilepsy and sexual dysfunction
• Chapter 5: Epilepsy, diabetes, and other endocrinological disorders
• Chapter 6: Epilepsy, coeliac disease and other inflammatory bowel diseases
• Chapter 7: Epilepsy and obesity: A complex interaction
• Chapter 8: Epilepsy and heart diseases
• Chapter 9: Epilepsy and cancer
• Chapter 10: Epilepsy, headache, and chronic pain
• Chapter 11: Epilepsy, obstructive sleep apnea syndrome, and other sleep disorders
• Chapter 12: Epilepsy and other neurological disorders
• Chapter 13: Epilepsy and cognition
• Chapter 14: Epilepsy and intellectual disabilities
• Chapter 15: Epilepsy and autistic spectrum disorder: Diagnostic challenges and treatment consideration
• Chapter 16: Epilepsy and mood disorders
• Chapter 17: Epilepsy and psychosis
• Chapter 18: Epilepsy and psychogenic nonepileptic seizures
• Chapter 19: Nursing issues in managing comorbidities of epilepsy
• Index