Factors contributing to excessive daytime sleepiness in Korean adults with epilepsy: A sleep questionnaire-based study

Prevalence of restless legs syndrome in adults with epilepsy: A systematic review and meta-analysis of observational studies

INTRODUCTION

Epilepsy is a common neurological disorder that significantly contributes to the worldwide disease burden. Restless legs syndrome is sleep-related movement disorder that causes uncomfortable sensations in the legs with an irresistible urge to move them. The aim of this study is to comprehensively assess the current evidence to estimate the prevalence of restless legs syndrome (RLS) in adults with epilepsy (AWE) and to compare it to healthy controls.

METHODS

PubMed, Medline, Scopus, and Web of Science databases were searched for observational studies reporting the prevalence of RLS in AWE. The modified Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the studies. Comprehensive Meta-Analysis software (version 3.0) was used to perform data analysis. The heterogeneity of the studies was assessed using the I2 index. The pooled prevalence of RLS in AWE and the odds ratio were calculated based on the random-effect model. Sensitivity analysis was assessed. A funnel plot and Egger's test were used to investigate publication bias. Subgroup analysis and univariate meta-regression analysis were done.

RESULTS

Based on the analysis of 17 studies (2262 AWE patients), the prevalence of RLS was 14.9 % (95%CI, 10.4%-21 %). This rate was highest in the Americas (35.3 %; 95 % CI: 19.7-54.9 %) and lowest in Asian countries (11.6 %). The risk of RLS was significantly higher in AWE patients compared to health controls (12 studies, OR = 2.09; 95 % CI: 1.53-2.85, I2 = 91.69 %, P < 0.001). subgroup analysis showed Variations in RLS rates between studies depending on quality scores, methodology, and diagnostic criteria. The funnel plot and Egger's test suggest there was publication bias. Sensitivity analysis showed that none of the studies on their own significantly affected the results.

CONCLUSIONS

This meta-analysis provides the first pooled estimate of RLS prevalence in AWE. RLS occurs in 15 out of every 100 AWE patients, and the risk is high compared to healthy controls. However, the findings need to be confirmed in future studies owing to limitations in the analysis and study design.

Restless leg syndrome prevalence in epilepsy patients and its impact on quality of sleep

This study aimed to determine the frequency of restless leg syndrome (RLS) and other sleep-related movement disorders and their effects on sleep quality in epilepsy patients. One hundred and twenty-seven epilepsy patients were compared with 115 age-and gender-matched healthy controls. RLS was determined from the clinical characteristics of the patients according to the International RLS Study Group's (IRLSSG) diagnostic criteria. Sleep bruxism was diagnosed based on the International Classification of Sleep Disorders, Third Edition (ICSD-3) criteria. Subjective sleep quality was evaluated with the Pittsburgh Sleep Quality Index (PSQI). Poor sleep quality was more common in the epilepsy group than in the control group (42.5% versus 26.1%; p = 0.007). The epilepsy group had significantly higher PSQI total scores than the control group (p = 0.003). The frequency of RLS was higher in epileptic patients than in the control group (13.4% versus 5.2%; p = 0.024). There were no significant differences between the patient group and the control group regarding limb movement and bruxism frequency during sleep. The PSQI scores were high in epilepsy patients with RLS compared to those without RLS (p = 0.009). The frequency of habitual snoring, bruxism, and repetitive leg movement in sleep was also high in epilepsy patients with RLS compared to those without RLS (p < 0.05). The prevalence of poor sleep quality and RLS in epilepsy patients is higher than in healthy controls. Our results also show the negative impact of RLS on sleep quality in epilepsy patients. Further confirmatory studies using objective sleep tests are needed to identify the mechanisms underlying the current findings.

High prevalence of pathological alertness and wakefulness on maintenance of wakefulness test in adults with focal-onset epilepsy

BACKGROUND

Excessive daytime sleepiness (EDS) is a common complaint in adults with epilepsy (AWE), but objective evaluation is lacking. We used the maintenance of wakefulness test (MWT) to objectively measure the ability of adults with focal-onset epilepsy to maintain wakefulness in soporific conditions.

METHODS

Adults with epilepsy participating in a study investigating the effects of lacosamide on sleep and wakefulness underwent baseline ambulatory polysomnography (PSG)/EEG followed by MWT. Mean sleep latency (MSL) and mean percent sleep time (MST, mean percentage of non-wake EEG scored in 3-sec bins from lights out to sleep onset averaged over the 4 MWT trials) were quantified. Subjective sleepiness was assessed by the Epworth Sleepiness Scale (ESS). Spearman correlation and linear regression assessed relationships between MWT parameters, ESS and relevant sleep and epilepsy-related variables.

RESULTS

Maintenance of wakefulness test MSL in 51 AWE (mean age 43.5 ± 13 years, 69% female, mean BMI 24.6 ± 11.2 kg/m²) was 21.7 ± 11.9 min; 45.1% had an abnormally short MSL <19.4 min and 15.7% <8 min. MST was 9.3% [3.3, 19.1]. Mean ESS score was 8.8 ± 5.7; 39% had elevated ESS (>10). No correlation between subjective ESS and objective MSL (p = 0.67) or MST (p = 0.61) was found. MSL was significantly shorter in subjects with focal to bilateral tonic-clonic seizures (FBTCS; 7.9 min [13.6, 22.3]) compared to those without (27.4 min [21.2, 33.6], p = 0.013). Younger subjects had shorter MSL; MSL increased 3.2 min for every 10-year increase in age.

CONCLUSION

We found a high prevalence of objective sleepiness/difficulty maintaining wakefulness on the MWT and subjective sleepiness using the ESS in AWE without a correlation between the two. More severe objective sleepiness was found in subjects with a history of FBTCS and younger age. Further research is needed to determine mechanistic underpinnings and optimal measurements of pathological sleepiness in people with epilepsy given the burden of it on quality of life.

The Epworth Sleepiness Scale in epilepsy: Internal consistency and disease-related associations

BACKGROUND

The Epworth Sleepiness Scale (ESS) is the most common instrument for measuring subjective sleep propensity in people with epilepsy but has not yet been validated in this population.

STUDY OBJECTIVES

We aimed to systematically assess the validity, performance, and internal consistency of the ESS, as well as correlations between the ESS and disease-specific variables and patient-reported outcome measures in a cohort of adults with epilepsy (AWE).

METHODS

Ninety-five AWE completed sleep and seizure diaries, in-laboratory polysomnography (PSG) and patient-reported outcome measures, including the ESS, Insomnia Severity Index (ISI), and the Beck Depression Inventory (BDI). Demographic information and data from 95 matched controls referred for PSG for suspected obstructive sleep apnea (OSA) was taken from the electronic medical record. Frequencies of high ESS item ratings (item score ≥2) were calculated for each group. Cronbach's α and factor analysis were performed to assess the internal consistency and validity of the ESS within cases and controls. Multivariable linear models were used to assess the association between ESS and predictors of interest, adjusting for demographic and disease-specific variables, including seizure type, frequency, and anti-seizure medication (ASM) therapy.

RESULTS

While suspected OSA controls had significantly greater mean ESS total scores (9.9 vs 7.9, p = 0.004) and proportion with ESS >10 (42% vs 25%, p = 0.014), there were no significant differences in the severity of item responses, with the exception of "lying down to rest in the afternoon when circumstances permit," for which more controls rated as likely/very likely (79% vs 64%), p = 0.024). AWE with ESS >10 had higher mean standardized ASM dose (2.5 vs 1.7, p = 0.026). All ESS items were significantly correlated with the total score within each group. Cronbach's α was 0.75 for cases and 0.85 for controls, indicating good internal consistency of the ESS for both groups. After adjusting for demographic and sleep characteristics, higher ESS scores were associated with greater insomnia scores on the ISI (p = 0.024) and depressive symptoms on the BDI (p = 0.018).

CONCLUSIONS

This study provides validity for the use of the ESS in adult populations with epilepsy.

The Quality of Life in Patients with Epilepsy in the Context of Sleep Problems and Sexual Satisfaction

Epilepsy influences the quality of patient functioning in almost all aspects of life. This study aimed to assess the quality of difficulties with sleep initiation and those concerning sexual function, and to assess whether sleep disorders are associated with selected aspects of sexual function and quality of life. The study involved completing a quality-of-life questionnaire for persons with epilepsy: a QOLIE-31 questionnaire, and the present authors' questionnaire, including 20 questions. A total of 170 questionnaires were completed by 89 men and 81 women. Sleep problems of various frequency were reported by 98 participants (57.6%). Only 41% of patients were definitely satisfied with their sex life. The respondents who declared dissatisfaction with their sex life more often reported difficulties with sleep initiation (χ2 = 10.20; p ≤ 0.001). Moreover, those who claimed that epilepsy might contribute to sex life problems more commonly declared dissatisfaction with their sex life (χ2 = 20.01; p ≤ 0.001) and more frequently, reported difficulties with sleep initiation (χ2 = 6.30; p ≤ 0.012). The issues should constitute the constant element of medical history taking, as improvement in these areas of functioning may promote better quality of life in patients with epilepsy.

Sleep quality and daytime sleepiness in epilepsy: Systematic review and meta-analysis of 25 studies including 8,196 individuals

We sought to gain a better understanding of the relationship between epilepsy and sleep quality and daytime sleepiness by performing a literature search of PubMed for case-control studies that compared patients with epilepsy to controls and reported the Pittsburgh sleep quality index (PSQI) and/or the Epworth sleepiness scale (ESS). Study-specific mean differences in the PSQI and ESS between cases and controls were extracted from the publications and pooled using random-effects meta-analysis. Twenty-five studies (2964 cases, 5232 controls) were included. Fifteen studies reported the PSQI and 24 the ESS. Mean age was 40 years; 50.4% were women. When comparing cases to controls, the pooled mean differences in the PSQI and ESS were 1.27 (95% confidence interval (CI): 0.76, 1.78; P < 0.001; I²: 81.4%) and 0.38 (95% CI: -0.07, 0.84; P = 0.099; I²: 81.0%). Subgroup analyses revealed that mean differences in the ESS were significantly lower in studies with a higher proportion of patients with focal epilepsy (P = 0.004). In this large-scale meta-analysis patients with epilepsy had a higher PSQI, close to the pathological cut-off, compared to controls, but a similar and unremarkable ESS. Further studies are needed to investigate potential effect modifiers, such as specific antiepileptic drugs or seizure frequency.

Obstructive sleep apnea risk in patients with focal versus generalized epilepsy

OBJECTIVE

Obstructive sleep apnea (OSA) is common in patients with epilepsy (PWE), and treatment may improve seizure control. However, OSA is often undiagnosed in PWE, and understanding of the risk profile for OSA is important. In this study, we sought to determine if OSA risk is similar in patients with generalized versus focal epilepsy.

METHODS

We recruited 115 patients presenting to the Rutgers-Robert Wood Johnson Epilepsy Clinic with focal or generalized epilepsy. Obstructive sleep apnea risk was assessed using the Sleep Apnea Scale of the Sleep Disorders Questionnaire (SA-SDQ). Sleepiness was assessed using the Epworth Sleepiness Scale (ESS). Demographic and clinical information was gathered from the electronic medical record. Unadjusted and adjusted analyses were carried out to assess differences in the SA-SDQ between patients with generalized versus focal epilepsy. Further analyses were done to assess the relationship between seizure frequency, epilepsy type, and the SA-SDQ.

RESULTS

Unadjusted mean SA-SDQ scores, as well as scores high enough to represent likely OSA, were similar in patients with generalized versus focal epilepsy. However, in adjusted analyses, patients with generalized epilepsy had a significantly higher mean SA-SDQ score. Older age, higher body mass index (BMI), and a history of hypertension (HTN) were also associated with higher SA-SDQ scores. Sleep Apnea Scale of the Sleep Disorders Questionnaire scores were not significantly affected by the presence of a seizure within the prior one month or six months. Average ESS scores and the percentage of scores consistent with an abnormal degree of sleepiness were statistically similar in patients with generalized versus focal epilepsy.

SIGNIFICANCE

Our study suggests that patients with generalized epilepsy have a higher risk of OSA. Further studies measuring OSA directly as well as assessing potential benefits of treatment are needed.

Sex differences in factors associated with daytime sleepiness and insomnia symptoms in persons with epilepsy

Clinical factors associated with daytime sleepiness and insomnia in persons with epilepsy (PWE) were examined in this cross-sectional study of 126 participants (men, 50.8%). Excessive daytime sleepiness (EDS; score of ≥11 on the Epworth Sleepiness Scale (ESS)) was noted in 17.5% of participants (mean score, 6.1 ± 4.2), and moderate-to-severe insomnia (Insomnia Severity Index (ISI) scores of ≥15) was noted in 20.6% (mean score, 7.8 ± 6.4). Linear regression analyses revealed that ESS scores were independently associated with obstructive sleep apnea (OSA; snoring, tiredness, observed apnea, high blood pressure, body mass index, age, neck circumference, and gender (STOP-Bang) score of ≥3), an antiepileptic drug (AED) load of >3, depression (Patient Health Questionnaire-9 (PHQ-9) score of ≥10), female sex, and nocturnal seizures. Insomnia Severity Indices were independently associated with depression and anxiety (Generalized Anxiety Disorder-7 (GAD-7) score of ≥7). Notably, significant sex differences were found. Epworth Sleepiness Scale scores were associated with OSA in men but were associated with depression in women. In addition, anxiety was associated with insomnia in women only. Overall, OSA and depression were the most important significant clinical factors associated with daytime sleepiness and insomnia, respectively. However, there were sex differences for the associations between individual factors and sleep disturbances.

Evaluation of sleep quality in spouses of people with epilepsy

OBJECTIVE

The objective of this study was to evaluate the spouses of people with epilepsy with and without a history of seizures during sleep in terms of depression, anxiety, and sleep quality.

METHODS AND MATERIALS

This prospective, cross-sectional study was conducted in three groups of 18-55 year olds, who were at least primary school graduates. The 1st group consisted of healthy spouses of 30 healthy volunteers with age and sex matched with the other groups. The 2nd group comprised spouses of 30 people with epilepsy who had been married for at least one year and had no history of seizures during sleep. The 3rd group consisted of spouses of 30 people with epilepsy who had been married for at least one year and had a history of at least one seizure during sleep in the course of the previous year. The questionnaire including demographic data, Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI), and the Beck Anxiety Inventory (BAI) was applied to all participants.

RESULTS

The mean age of the 1st group was 35.07 ± 8.33 years, that of the 2nd group was 36.47 ± 7.63 years, and that of the 3rd group was 35.33 ± 6.05 years. There was no significant age difference between the groups (p = 0.740). The depression scores of the 2nd and the 3rd groups were significantly higher than that of the 1st group (p < 0.001, for both). The anxiety scores of the 3rd group were significantly higher than those of the 1st and the 2nd groups (p < 0.001 and p = 0.001, respectively). Thirty percent (n = 9) of the 1st group, 40% (n = 12) of the 2nd group, and 70% (n = 21) of the 3rd group had poor sleep quality. The sleep disorder rate in the 3rd group was significantly higher than in the 1st and the 2nd groups (p = 0.002 and p = 0.020, respectively). When the PSQI subscales were examined, the sleep quality, sleep latency, usual sleep efficiency, daytime dysfunction, and the total sleep total score were significantly higher in the 3rd group than the 1st and the 2nd groups. The patients in the third group had significantly higher scores of sleep duration, sleep disturbance, and sleep medication use than those in the 1st group.

CONCLUSION

We found out that the PSQI score, which reflected the sleep quality, was poor in the spouses of people with epilepsy, who had seizures during sleep. To the best of our knowledge, these findings are the first in the literature on this subject.