Epilepsy and Sleep
How does sleep impact epilepsy?
Andrew Bagshaw is a Professor of Imaging Neuroscience at the University of Birmingham and has been a member of Epilepsy Research UK’s Scientific Advisory Committee for the past five years. In this blog, Andrew discusses the many ways in which sleep is important and its relevance for epilepsy.
Sleep is important. We might not know exactly what it is for, or how it works, but all of us know that we need it. Have a night without sleep, or a night where you keep waking up, and the next day will be difficult. You’ll be struggling to stay awake, probably feeling low in mood and irritable, finding it difficult to think clearly, and may find yourself snacking continuously. This is because sleep is needed to help your brain and body function properly. There probably isn’t a single process in the brain or body that gets better with bad sleep.
Sleep is also intimately entwined with epilepsy. Some people only have seizures when they are sleeping, while for many a poor night’s sleep can increase the risk of a seizure the next day. This was noted around two and a half thousand years ago by Hippocrates, often called the father of modern medicine. Not only was he among the first to recognise that epilepsy and seizures come from the brain, but he suggested that people with epilepsy should ‘spend the day awake and the night asleep. If this habit be disturbed, it is not so good … worse of all when he sleeps neither night nor day’.
Unfortunately, many studies have demonstrated that adults and children with epilepsy generally have poorer sleep than people without epilepsy. Recently, we combined the results of studies that examined sleep in around 900 children with epilepsy and 1500 children without epilepsy. Children with epilepsy had shorter durations of sleep and worse sleep quality than their peers without epilepsy, as well as being more likely to suffer from sleep difficulties like night waking and sleep walking.
How can we understand more about the relationship between epilepsy and sleep? First, we need to consider what aspect of sleep we want to consider. Sleep is not a single thing, it is a complex behaviour with many facets that takes up around a third of our lives as adults, and more as children. Saying that epilepsy and sleep are linked isn’t very helpful, it’s like saying that epilepsy is linked with being awake. What aspect of being awake is important – how much exercise someone does, what they eat, the stresses they face, their mood? All these factors would need to be considered, and it’s the same with sleep. We can look at the amount of sleep a person gets, their sleep quality in terms of whether they find it difficult to get to sleep or wake up in the night, or the daytime consequences of poor sleep described above. Equally important might be the changes to brain activity that come about during sleep, or how sleep habits relate to waking brain function. At the minute, we really don’t know enough about sleep to be able to predict which aspects are the most important.
Over the past few years, we’ve used a range of approaches to understand how sleep affects the brain, and how sleep and epilepsy are linked. We’ve had people with and without epilepsy sleeping inside the MRI scanner, with electrodes on their scalp (this isn’t for everyone, but it’s not as bad as it sounds!). We’ve looked at differences in brain structure and function between short and long sleepers, and between early and late sleepers. We’ve used watches similar to fitness trackers to give us an idea of people’s sleep over a couple of weeks following their normal schedule. We’ve also looked at how the relationship between sleep and epilepsy is impacted by traits of autism and ADHD (which tend to be higher in people with epilepsy, and are themselves associated with sleep disruptions). All these approaches are needed because sleep is complex and multi-faceted. Slowly, they’re enabling a clearer picture of how sleep affects the brain, and what that means for people with epilepsy.
TBI Rehabilitation 