Changes in Sleep Pattern During the COVID-19 Lockdown in Patients With Narcolepsy, Idiopathic Hypersomnia, and Restless Legs Syndrome

Diagnostic challenges and burden of idiopathic hypersomnia: a systematic literature review

Idiopathic hypersomnia (IH) is a rare neurological sleep disorder, characterized by excessive daytime sleepiness despite normal sleep duration, that can significantly impact patient's lives. The burden of IH goes beyond excessive daytime sleepiness, pervading all aspects of everyday life. Characteristic and burdensome symptoms of IH include sleep inertia/drunkenness, long sleep duration, and daytime cognitive dysfunction. This systematic review assessed current knowledge regarding IH diagnostic challenges and burden of illness. Literature searches for original epidemiological, clinical, humanistic, or economic research relevant to IH published between 2012 and 2022 in MEDLINE, Embase, Cochrane, gray literature (diagnostic criteria and treatment guidelines), conferences (2019-2022), and clinical trial databases yielded 97 articles. Findings indicate that IH remains a poorly defined diagnosis of exclusion that is difficult to distinguish from narcolepsy type 2 because of symptom overlap and inadequacies of objective testing. Consequently, individuals with IH endure diagnostic delays of up to 9 years. The economic burden of IH has not been characterized to any appreciable extent. Pharmacological treatment options can improve symptoms and functional status, but rarely restores normal levels of functioning. These findings highlight the need to reclassify central disorders of hypersomnolence. Further collaboration is now required between research groups to identify and validate objective markers to help redefine diagnostic criteria for IH. This would move IH into a position that could benefit from future targeted therapeutic interventions. The study was funded by Takeda Development Center Americas, Inc.

Long-term follow-up of symptom and quality of life changes in patients with narcolepsy during and after the COVID-19 pandemic

The COVID-19 pandemic may have a significant impact on patients with narcolepsy, yet a long-term follow-up study is currently lacking. This study aims to investigate changes in symptom severity and the quality of life of patients with narcolepsy during and after the pandemic. Patients with type 1 or type 2 narcolepsy (NT1, NT2) were retrospectively recruited and prospectively followed from 2020 to 2023. They received evaluations including the Epworth Sleepiness Scale (ESS), the visual analog scale (VAS) for hypersomnolence, the VAS for cataplexy, the Short-form 36 Health Survey questionnaire (SF-36), and a sleep diary. We compared the differences between the pre-lockdown, the lockdown, the post-lockdown, and the post-pandemic periods by repeated measures ANOVA or the Friedman test, with the Bonferroni test for post hoc analysis. A total of 100 patients completed the 4-year study (mean age, 24.06 ± 7.00 years; 55% male). We observed significant differences in the ESS (p = 0.037), total nighttime sleep (p = 0.03), total sleep time (p = 0.035), and sleep efficiency (p = 0.035) during the study period. There was also significantly worse physical role functioning in the post-pandemic period (p = 0.014). In particular, the NT1 group had significantly decreased VAS-C scores (p < 0.001) but experienced worse physical role functioning in the post-pandemic period (p = 0.009). Patients with narcolepsy continue to face challenges after the pandemic. A more flexible lifestyle with an adequate sleep time may be beneficial, and medication adherence should be emphasized.

Restless legs symptoms increased during COVID-19 pandemic. International ICOSS-survey

BACKGROUND AND OBJECTIVES

Restless legs syndrome (RLS) has been associated with anxiety, depression, insomnia, lifestyle factors and infections. We aimed to study the prevalence of symptoms of RLS during the COVID-19 pandemic versus pre-pandemic. We hypothesized that pre-existing RLS symptoms worsened and pandemic-related factors may have triggered new symptoms of RLS.

METHODS

Adults (≥18 years) from fifteen countries across four continents participated in an online survey between May and August 2020. The harmonized questionnaire included a validated single question on RLS with response alternatives from 1 to 5 on a scale from never to every/almost every evening or night. Other measures were the Insomnia Severity Index (ISI), measures of symptoms of anxiety (GAD-2) and depression (PHQ-2), and questions on different pandemic-related factors.

RESULTS

Altogether, 17 846 subjects (63.8 % women) were included in the final analyses. The mean age was 41.4 years (SD 16.1). During the pandemic, symptoms of RLS (≥3 evenings/nights per week) were more common 9.1 % (95 % CI 8.7-10.1) compared to 5.4 % (95 % CI 4.9-6.0) before the pandemic (P < 0.0001). Alltogether 1.3 % (95 % CI 1.1-1.6) respondents had new-onset symptoms (≥3 evenings/nights per week). Moderate-severe insomnia was strongly associated with RLS symptoms. The occurrences of new-onset RLS symptoms were 5.6 % (95 % CI 0.9-13.0) for participants reporting COVID-19 and 1.1 % (95 % CI 0.7-1.5) for non-COVID-19 participants. In the fully adjusted logistic regression model, the occurrence of new-onset RLS symptoms was associated with younger age, social restrictions and insomnia severity. In a similar analysis, RLS symptoms (≥3 evenings/nights per week) were associated with lower education, financial hardship, sleep apnea symptoms, use of hypnotics, insomnia severity, symptoms of depression and possible post-traumatic stress disorder.

DISCUSSION

Our findings indicate that RLS symptoms were more common during the pandemic than before. Usually, the prevalence of RLS increases with age. However, during the pandemic, new-onset symptoms of RLS were more common in younger age groups. This may be due to the pandemic-related factors being more pronounced in the younger compared to the older. The association between insomnia, psychiatric symptoms and RLS warrants clinical attention.

Long sleep time and excessive need for sleep: State of the art and perspectives

The mechanisms underlying the individual need for sleep are unclear. Sleep duration is indeed influenced by multiple factors, such as genetic background, circadian and homeostatic processes, environmental factors, and sometimes transient disturbances such as infections. In some cases, the need for sleep dramatically and chronically increases, inducing a daily-life disability. This "excessive need for sleep" (ENS) was recently proposed and defined in a European Position Paper as a dimension of the hypersomnolence spectrum, "hypersomnia" being the objectified complaint of ENS. The most severe form of ENS has been described in Idiopathic Hypersomnia, a rare neurological disorder, but this disabling symptom can be also found in other hypersomnolence conditions. Because ENS has been defined recently, it remains a symptom poorly investigated and understood. However, protocols of long-term polysomnography recordings have been reported by expert centers in the last decades and open the way to a better understanding of ENS through a neurophysiological approach. In this narrative review, we will 1) present data related to the physiological and pathological variability of sleep duration and their mechanisms, 2) describe the published long-term polysomnography recording protocols, and 3) describe current neurophysiological tools to study sleep microstructure and discuss perspectives for a better understanding of ENS.

Prevalence of poor sleep quality in COVID-19 patients: a systematic review and meta-analysis

Objective

The coronavirus disease (COVID-19) and the public health responses were associated with a huge health burden, which could influence sleep quality. This meta-analysis and systematic review examined the prevalence of poor sleep quality in COVID-19 patients.

Methods

PubMed, Web of Science, Embase, and PsycINFO were systematically searched from their respective inception to October 27, 2022. Prevalence rates of poor sleep were analyzed using a random effects model.

Results

Totally, 24 epidemiological and 12 comparative studies with 8,146 COVID-19 patients and 5,787 healthy controls were included. The pooled prevalence of poor sleep quality based on the included studies was 65.0% (95%CI: 59.56-70.44%, I2 = 97.6%). COVID-19 patients had a higher risk of poor sleep quality compared to healthy controls (OR = 1.73, 95% CI: 1.30-2.30, p < 0.01, I2 = 78.1%) based on the 12 comparative studies. Subgroup analysis revealed that COVID-19 patients in low-income countries (p = 0.011) and in studies using a lower Pittsburgh Sleep Quality Index score cut-off (p < 0.001) were more likely to have poor sleep quality. Meta-regression analyses revealed that being female (p = 0.044), older (p < 0.001) and married (p = 0.009) were significantly correlated with a higher risk of poor sleep quality while quality score (p = 0.014) were negatively correlated with the prevalence of poor sleep quality in COVID-19 patients.

Conclusion

Poor sleep quality was found to be very common in COVID-19 patients. Considering the negative effects of poor sleep quality on daily life, sleep quality should be routinely assessed and appropriately addressed in COVID-19 patients.

Idiopathic hypersomnia and Kleine-Levin syndrome

Idiopathic hypersomnia (IH) and Kleine-Levin syndrome (KLS) are rare disorders of central hypersomnolence of unknown cause, affecting young people. However, increased sleep time and excessive daytime sleepiness (EDS) occur daily for years in IH, whereas they occur as relapsing/remitting episodes associated with cognitive and behavioural disturbances in KLS. Idiopathic hypersomnia is characterized by EDS, prolonged, unrefreshing sleep at night and during naps, and frequent morning sleep inertia, but rare sleep attacks, no cataplexy and sleep onset in REM periods as in narcolepsy. The diagnosis requires: (i) ruling out common causes of hypersomnolence, including mostly sleep apnea, insufficient sleep syndrome, psychiatric hypersomnia and narcolepsy; and (ii) obtaining objective EDS measures (mean latency at the multiple sleep latency test≤8min) or increased sleep time (sleep time>11h during a 18-24h bed rest). Treatment is similar to narcolepsy (except for preventive naps), including adapted work schedules, and off label use (after agreement from reference/competence centres) of modafinil, sodium oxybate, pitolisant, methylphenidate and solriamfetol. The diagnosis of KLS requires: (i) a reliable history of distinct episodes of one to several weeks; (ii) episodes contain severe hypersomnia (sleep>15h/d) associated with cognitive impairment (mental confusion and slowness, amnesia), derealisation, major apathy or disinhibited behaviour (hypersexuality, megaphagia, rudeness); and (iii) return to baseline sleep, cognition, behaviour and mood after episodes. EEG may contain slow rhythms during episodes, and rules out epilepsy. Functional brain imaging indicates hypoactivity of posterior associative cortex and hippocampus during symptomatic and asymptomatic periods. KLS attenuates with time when starting during teenage, including less frequent and less severe episodes. Adequate sleep habits, avoidance of alcohol and infections, as well as lithium and sometimes valproate (off label, after agreement from reference centres) help reducing the frequency and severity of episodes, and IV methylprednisolone helps reducing long (>30d) episode duration.

Impact of Taiwan's 2021 COVID-19 lockdown on the symptom severity and quality of life of patients with narcolepsy

COVID-19 lockdowns can influence the sleep quality and daytime condition of patients with narcolepsy. Using data from our cohort study, we investigated changes in the quality of life and the symptom severity of patients with narcolepsy during Taiwan's 2021 lockdown and investigated differences by narcolepsy subtype, sex, and age. Patients with type 1 and type 2 narcolepsy (NT1 and NT2, respectively) aged 6-40 years were retrospectively recruited from our narcolepsy cohort study. These patients were regularly evaluated using the Short Form 36 Health Survey questionnaire (SF-36), the Epworth Sleepiness Scale (ESS), the visual analog scale (VAS) for hypersomnolence, the VAS for cataplexy and sleep diary. We compared the differences between the lockdown and the prelockdown periods by narcolepsy subtype, sex, and age. We used a paired t test analysis to compare differences in the SF-36, ESS, VAS scores and data of sleep diary between the prelockdown and lockdown periods (p1), and an independent t test analysis was used to compare the changes in different subgroups between the prelockdown and lockdown periods (p2). A total of 120 patients with narcolepsy were recruited (mean age 24.22 ± 6.87 years; 58% male); 80 of the patients had NT1 (mean age 25.25 ± 6.79 years; 60% male) and 40 had NT2 (mean age 22.16 ± 6.64, 53% male). During the lockdown period, the ESS score of total patients was decreased (p = 0.039) and body mass index was increased (p = 0.02). The NT1 group decreased significantly (p1 = 0.017), especially in men (p1 = 0.016) and adults (p1 = 0.04); scores for the VT domain of the SF-36 increased significantly in male and adult patients with NT2 (p1 = 0.048 and 0.012). Additionally, male patients with NT2 exhibited significantly decreased scores in the physical and emotional role functioning domains (p1 = 0.028, 0.024). The children and adolescents with NT1 had significantly decreased scores in the general health domain of the SF-36, but no significant change was noted in that of adults (p1 = 0.027, p2 = 0.012). We observed both negative and positive impacts of Taiwan's 2021 lockdown on patients with narcolepsy. A more flexible but structured daily routine with adequate sleep time should be considered for this population during lockdown and nonlockdown periods.

Association between hypersomnolence and the COVID-19 pandemic: The International COVID-19 Sleep Study (ICOSS)

BACKGROUND

The COVID-19 pandemic and related restriction measures have affected our daily life, sleep, and circadian rhythms worldwide. Their effects on hypersomnolence and fatigue remain unclear.

METHODS

The International COVID-19 Sleep Study questionnaire which included items on hypersomnolence such as excessive daytime sleepiness (EDS), and excessive quantity of sleep (EQS), as well as sociodemographic factors, sleep patterns, psychological symptoms, and quality of life was distributed in 15 countries across the world from May to September in 2020.

RESULTS

Altogether responses from 18,785 survey participants (65% women, median age 39 years) were available for analysis. Only 2.8% reported having had COVID-19. Compared to before the pandemic, the prevalence of EDS, EQS, and fatigue increased from 17.9% to 25.5%, 1.6%-4.9%, and 19.4%-28.3% amid the pandemic, respectively. In univariate logistic regression models, reports of having a COVID-19 were associated with EQS (OR 5.3; 95%-CI 3.6-8.0), EDS (2.6; 2.0-3.4), and fatigue (2.8; 2.1-3.6). In adjusted multivariate logistic regression, sleep duration shorter than desired (3.9; 3.2-4.7), depressive symptoms (3.1; 2.7-3.5), use of hypnotics (2.3; 1.9-2.8), and having reported COVID-19 (1.9; 1.3-2.6) remained strong predictors of EDS. Similar associations emerged for fatigue. In the multivariate model, depressive symptoms (4.1; 3.6-4.6) and reports of having COVID-19 (2.0; 1.4-2.8) remained associated with EQS.

CONCLUSIONS

A large increase in EDS, EQS, and fatigue occurred due to the COVID-19 pandemic, and especially in self-reported cases of COVID-19. These findings warrant a thorough understanding of their pathophysiology to target prevention and treatment strategies for long COVID condition.

Clinical considerations for the diagnosis of idiopathic hypersomnia

Idiopathic hypersomnia is a sleep disorder of neurologic origin characterized by excessive daytime sleepiness, with sleep inertia, long, unrefreshing naps, and prolonged nighttime sleep being key symptoms in many patients. Idiopathic hypersomnia is described in the International Classification of Sleep Disorders, 3rd Edition as a central disorder of hypersomnolence with distinct clinical features and diagnostic criteria; however, confirming the diagnosis of idiopathic hypersomnia is often challenging. Diagnosis of idiopathic hypersomnia is based on objective sleep testing and the presence of associated clinical features but may be difficult for clinicians to recognize and correctly diagnose because of its low prevalence, clinical heterogeneity, and symptoms, which are similar to those of other sleep disorders. The testing required for diagnosis of idiopathic hypersomnia also presents logistical barriers, and reliability of objective sleep measures is suboptimal. The pathophysiology of idiopathic hypersomnia remains unknown. In this review, clinical considerations related to the pathogenesis, diagnosis, and management of idiopathic hypersomnia will be discussed, including perspectives from the European Union and United States.