Readers' choice September 2012

Seizure: Septemeber 2012

View contents and summaries provided by  

Readers' choice

Each month our Seizure Reviewers read the summaries of the articles in the latest issue of Seizure. They then decide which one should be readers' choice.

• Find out about being a Seizure Reviewer

Markedly disturbed sleep in medically refractory compared to controlled epilepsy - A clinical and polysomnography study 

Paresh Zanzmera, Garima Shukla , Anupama Gupta, Hariom Singh, Vinay Goyal, Achal Srivastava, Madhuri Behari
Department of Neurology, All India Institute of Medical Sciences, New Delhi, India

Abstract

Purpose

To evaluate sleep disturbances or sleep related events and their characteristics among patients with medically refractory epilepsy, compared to those with controlled epilepsy.

Methods

In a prospective case-controlled study, patients of medically refractory and controlled epilepsy were recruited and history pertaining to epilepsy and sleep related events and Epworth sleepiness scores were recorded and all patients underwent overnight polysomnography.

Results

Among 40 patients, 20 with medically refractory (Group 1) and 20 with controlled epilepsy (Group 2) (median age 18, range 10–35 years), the self reported sleep parameters in Group 1 patients were found to be significantly different as compared to Group 2, in terms of the duration of night time sleep, day time sleep, day time nap frequency, total sleep hours per day, excessive daytime sleepiness (EDS)(45% vs. 15%) and average sleep hours over the week prior to polysomnography. On PSG, Group 1 patients showed significantly less total sleep time [340.4 min (147–673) vs. 450.3 min (330–570)] with delayed sleep latency and REM latency, poor sleep efficiency [80.45 (40.5–98.0) vs. 95.45 (88.4–99.7)] and frequent arousals and wake after sleep onset (WASO) compared to Group 2 patients. Four patients (20%) in Group 1 compared to none in Group 2 were found to have mild obstructive sleep apnea.

Conclusions

Our results indicate that medically refractory epilepsy patients believe that they spend more time sleeping, in contrast to the documented shorter sleep duration on polysomnography. This difference between perceived and actual sleep seems, by their data, to arise mainly from sleep fragmentation, disturbed architecture and the interesting finding of associated sleep apnea among the medically refractory epilepsy patients.

Why I chose this article

By Jim Camp – Seizure reviewer

Jim is 45, and works as a civil servant in London. He has been diagnosed with epilepsy for many years, and is keen to do what he can to help other people who have epilepsy.

What was the aim of the study?

The aim of this study was to compare the quality of sleep experienced by two groups of epilepsy patients. In the first group, the epilepsy was uncontrolled, while in the second group it was controlled.

How was the research carried out?

The two groups numbered 20 each. Each patient gave details of his or her medical history by completing a questionnaire. They gave details of their sleeping patterns in a second questionnaire. They also completed a sleep log for one week prior to the study. During the study itself, researchers looked in detail at the sleep activity of each patient. The parameters they measured included total sleep time, the time taken to fall asleep, the time taken to reach deep (REM) sleep, the number of awakenings and the number of limb movements while asleep. The study was completed over a period of 24 hours, so that daytime naps were included as well as overnight sleep.

What did the researchers find out?

The researchers found that the total sleep time of patients with uncontrolled epilepsy is considerably less than the patients themselves reported it to be. This is in contrast to the group with controlled epilepsy, who gave a much more accurate estimate of their sleep time. The research team accounts for this difference by pointing out that those with uncontrolled epilepsy are more likely to awaken during sleep, to suffer from disturbed sleep due to epilepsy, and they are also more likely to have sleep apnoea (interrupted breathing during sleep).

Why is this research important to people with epilepsy?

This study is important because it is the first of its kind. No other study has compared the sleep patterns of those suffering from difficult to control epilepsy with those who have controlled epilepsy. This opens up a new area of research. The finding that those with difficult to control epilepsy are not able to estimate accurately their sleep time is particularly significant. More studies, including studies with more subjects, will be required to confirm this finding. Identifying and remedying sleep problems will lead to an overall improvement in quality of life, and may also reduce the onset of seizures.

Why I like this study

I like this study because it is original, easy to understand and it has come up with important new findings.

Interview with the author - Dr Garima Shukla, MD, DM

How did you become interested in epilepsy?

As a student of neurology, several years back, the twinkle in the eyes of people with epilepsy whom I could help thrilled me. I found this most rewarding and chose epilepsy as my area of special interest.

What issues inspired you to carry out this research?

Not just us physicians, but all people dealing with epilepsy observe the impact of epilepsy on sleep. This might be the question of sleepiness during the day. sleepiness immediately after taking medication or disturbed night-time sleep. My other area of interest is sleep medicine. Therefore, the variation in sleep quality and daytime functioning of patients motivated me to take a closer look at patients who respond extremely well to medications, and those who don’t do too well with medications.

What methods did you use and why?

We chose patients with both controlled and uncontrolled epilepsy. All the patients completed questionnaires about their epilepsy and sleep quality. They also filled in sleep logs. Patients then took part in sleep tests at our hospital sleep laboratory. The tests recorded the patients’ breathing and movements during the different stages of sleep.

What did you find out?

We found that while patients with refractory epilepsy (difficult to control with medications) said they slept for long periods, their tests showed them to have a significantly shorter total sleep time than they reported. They also woke frequently and showed disturbances in all stages of sleep. Consequently, we found that these patients were much more sleepy in the daytime.

What impact do you think your findings will have on diagnosis, treatment and care?

We feel that our findings have important bearing on the way we treat our patients. Many doctors treat daytime sleepiness in patients with epilepsy, with drugs. However, our research shows the potential of improving night-time sleep before doing this. This can be done by choosing the right anti-epileptic drugs. If required, sedatives may be also given at night.

What further research is needed in this area?

The next step in future research in this area would be to evaluate the proposed treatment above.

What other research are you involved with at the moment?

At present, we are actively studying various aspects of sleep in patients with epilepsy. In particular, the effects of sleep on the areas in the brain where seizures arise.