Yasunori Oka

Development of a Japanese version of the Epworth Sleepiness Scale (JESS) based on Item Response Theory

BACKGROUND Various Japanese versions of the Epworth Sleepiness Scale (ESS) have been used, but none was developed via standard procedures. Here we report on the construction and testing of the developer-authorized Japanese version of the ESS (JESS). METHODS Developing the JESS involved translations, back translations, a pilot study, and psychometric testing. We identified questions in the ESS that were difficult to answer or were inappropriate in Japan, proposed possible replacements for those questions, and tested them with analyses based on item response theory (IRT) and classical test theory. The subjects were healthy people and patients with narcolepsy, idiopathic hypersomnia, or obstructive sleep apnea syndrome. RESULTS We identified two of our proposed questions as appropriate replacements for two problematic questions in the ESS. The JESS had very few missing data. Internal consistency reliability and test-retest reliability were high. The patients had significantly higher JESS scores than did the healthy people, and higher JESS scores were associated with worse daytime function, as measured with the Pittsburgh Sleep Quality Index. CONCLUSIONS In Japan, the JESS provides reliable and valid information on daytime sleepiness. Researchers who use the ESS with other populations should combine their knowledge of local conditions with the results of psychometric tests.

Low CSF hypocretin-1/orexin-A associated with hypersomnia secondary to hypothalamic lesion in a case of multiple sclerosis

Sirs: Hypocretins/orexins are hypothalamic neuropeptides that are related to sleep-wake regulation [1, 10]. It has been reported that cerebrospinal fluid (CSF) hypocretin1/orexin-A level is dramatically decreased in narcolepsy-cataplexy [4, 8, 9, 11]. Narcolepsy is also known to occur secondary to hypothalamic lesions caused by tumors, stroke, multiple sclerosis (MS) or acute disseminated encephalomyelitis, and the CSF hypocretin-1 level is decreased in some of them [5–7, 12]. However, it remains unclear whether CSF hypocretin level correlates with the severity of hypersomnia and the REM pathology. We reported the MRI finding of bilateral hypothalamic lesions in a case of MS presenting with hypersomnia [3]. We further examined details of sleep investigations and correlated them with CSF hypocretin-1 level and the MRI findings. A 22-year-old woman was admitted to our hospital one week after the acute onset of hypersomnia. She had developed diplopia as an initial symptom of MS one year before the onset of hypersomnia. She also complained of numbness of the lower extremities and polyuria. She did not experience any narcolepsy-related symptoms such as cataplexy, sleep paralysis and hypnagogic hallucination. MRI revealed bilateral FLAIR hyperintensity in the hypothalamus [3]. CSF showed increased myelin basic protein (242 pg/mL; normal < 100 pg/mL). CSF hypocretin-1 level was measured using radioimmunoassay kit (Phenix Pharmaceuticals, USA). HLA was positive for DR-4 and DR-6 but negative for DR-2. Sleep investigations including polysomnography (PSG) followed by multiple sleep latency test (MSLT) were performed 11days after the onset of hypersomnia. Methylprednisolone (1000 mg/day for 3 days) was started on the following day which was followed by oral prednisolone therapy, and her clinical symptom resolved within two weeks after methylprednisolone therapy was started. CSF hypocretin-1 level was undetectable (< 40 pg/mL; normal 200–350 pg/mL) on the first evaluation (Table 1). PSG showed sleep onset REM period (SOREMP), and confirmed the absence of any other sleep disorders. MSLT showed a mean sleep latency of 2.8 minutes and five SOREMPs out of five sessions. On the second evaluation two months later, the patient had no complaint of hypersomnia. Hypothalamic lesions were diminished. MSLT showed a mean sleep latency of 17.4 minutes and SOREMP appeared only once. CSF hypocretin-1 level was 167 pg/mL. On the third evaluation four months after the first one, MSLT showed a mean sleep latency of 14.8 minutes and no SOREMP. CSF hypocretin level was normal (211 pg/mL). This patient showed acute onset of hypersomnia but did not show cataplexy or any other narcolepsyrelated symptoms. Our case does not fulfill the diagnostic criteria of narcolepsy because the diagnosis of narcolepsy requires either cataplexy or other narcolepsy-related LETTER TO THE EDITORS

Night‐time frequency, sleep disturbance and general health‐related quality of life: Is there a relation?

Objectives:  We conducted a community‐based study to determine the relationship among night‐time frequency, sleep disturbance and general health‐related quality of life (GHQL).

Differences and associations between nocturnal voiding/nocturia and sleep disorders

Study Type – Symptom prevalence (prospective cohort)
Level of Evidence 1b

Differences in relationships among sleep apnoea, glucose level, sleep duration and sleepiness between persons with and without type 2 diabetes

Obstructive sleep apnoea is common in patients with diabetes. Recently, it was reported that short sleep duration and sleepiness had deleterious effects on glucose metabolism. Thereafter, several reports showed relationships between glucose metabolism and obstructive sleep apnoea, sleep duration or sleepiness. But the interrelationships among those factors based on recent epidemiological data have not been examined. We analysed data on 275 male employees (age, 44 ± 8 years; body mass index, 23.9 ± 3.1 kg m−2) who underwent a cross‐sectional health examination in Japan. We measured fasting plasma glucose, sleep duration using a sleep diary and an actigraph for 7 days, and respiratory disturbance index with a type 3 portable monitor for two nights. Fifty‐four subjects (19.6%) had impaired glucose metabolism, with 21 having diabetes. Of those 21 (body mass index, 25.9 ± 3.8 kg m−2), 17 (81.0%) had obstructive sleep apnoea (respiratory disturbance index ≥ 5). Regarding the severity of obstructive sleep apnoea, 10, four and three had mild, moderate and severe obstructive sleep apnoea, respectively. The prevalence of obstructive sleep apnoea was greater in those with than without diabetes (P = 0.037). Multiple regression analyses showed that the respiratory disturbance index independently related to fasting plasma glucose only in the diabetic subjects. In patients with diabetes, after adjustment for age, waist circumference, etc. sleep fragmentation had a greater correlation with fasting plasma glucose than sleep duration, but without significance (P = 0.10). Because the prevalence of obstructive sleep apnoea is extremely high in patients with diabetes, sufficient sleep duration with treatment for obstructive sleep apnoea, which ameliorates sleep fragmentation, might improve fasting plasma glucose.

Association Between Sleep Apnea, Sleep Duration, and Serum Lipid Profile in an Urban, Male, Working Population in Japan

BACKGROUND Dyslipidemia is often comorbid with obstructive sleep apnea (OSA), but few population-based studies have investigated their relationship. Short sleep duration is associated with hypertension and diabetes; however, its association with dyslipidemia is not well known. We investigated relationships among OSA, sleep duration, and the lipid profile in a community-based study. METHODS We measured the respiratory disturbance index (RDI) and sleep duration by a type 3 portable device and actigraph in 275 men in a Japanese company. Fasting blood parameters were obtained from periodic inspection data. RESULTS According to Japanese criteria, 143 subjects had dyslipidemia. Percent sleep time of oxygen saturation as measured by pulse oximetry (SpO2) < 90% and prevalence of severe OSA were greater and sleep duration and mean SpO2 during sleep were lower in subjects with dyslipidemia than in those without. Univariate analysis showed that the RDI was positively correlated with serum triglyceride (TG) levels (ρ = 0.20, P < .01), and sleep duration was negatively correlated with serum total cholesterol (TC) levels (γ = -0.13, P = .03) and serum low-density lipoprotein cholesterol levels (γ = -0.12, P = .04). Stepwise multiple regression analysis revealed that TG was correlated with RDI (β = 0.14, P = .02), BMI (β = 0.20, P < .01), and alcohol intake (β = 0.20, P < .01), and that TC was correlated with sleep duration (β = -0.13, P = .03), age (β = 0.15, P = .02), and waist/hip ratio (β = 0.15, P = .02). CONCLUSIONS Short sleep duration was associated with TC levels and RDI was positively associated with TG levels among working-aged men in an urban Japanese company. Correcting the status of OSA and/or short sleep duration might improve the lipid profile and cardiovascular consequences.

Internet addiction: Prevalence and relation with mental states in adolescents

Internet addiction disrupts the daily lives of adolescents. We investigated the prevalence of Internet addiction in junior high school students, elucidated the relation between Internet addiction and mental states, and determined the factors associated with Internet addiction in adolescents.

Age- and sex-related emotional and behavioral problems in children with autism spectrum disorders: Comparison with control children

Children with autism spectrum disorders (ASD) often present with emotional and behavioral problems, which could change the clinical course, especially during childhood, and affect future quality of life. The aim of this study was to clarify the age‐ and sex‐related differences of these problems in ASD.

The Melatonin Receptor Agonist Ramelteon Effectively Treats Insomnia and Behavioral Symptoms in Autistic Disorder

Children with autism spectrum disorders (ASD), including autistic disorder, frequently suffer from comorbid sleep problems. An altered melatonin rhythm is considered to underlie the impairment in sleep onset and maintenance in ASD. We report three cases with autistic disorder in whom nocturnal symptoms improved with ramelteon, a selective melatonin receptor agonist. Insomnia and behavior, assessed using the Clinical Global Impression-Improvement Scale, improved in two cases with 2 mg ramelteon and in the third case with 8 mg ramelteon. Our findings demonstrate that ramelteon is effective not only for insomnia, but for behavioral problems as well, in patients with autistic disorder.

Efficacy and safety of rotigotine in Japanese patients with restless legs syndrome: a phase 3, multicenter, randomized, placebo-controlled, double-blind, parallel-group study

OBJECTIVE We aimed to ascertain the efficacy and safety of transdermal rotigotine (2 and 3mg/24h) in Japanese patients with restless legs syndrome (RLS). METHODS In our double-blind placebo-controlled study, 284 Japanese patients with idiopathic RLS were randomly assigned to receive rotigotine 2mg/24h or 3mg/24h, or placebo, for 13 weeks. The primary endpoint was the change in International Restless Legs Syndrome Study Group rating scale (IRLS) total score. RESULTS The placebo-subtracted decreases in IRLS total score for rotigotine 2 mg/24 h and 3 mg/24 h were -2.8±1.3 and -3.1±1.3, respectively, which were significant (P<0.05). The interaction between baseline Pittsburgh Sleep Quality Index (PSQI) and treatment group for the change in IRLS total score was significant, indicating greater improvements in IRLS total score in patients with severe insomnia. Overall, 80.0%, 86.2%, and 51.6% of patients in the rotigotine 2 mg/24 h, 3 mg/24 h, and placebo groups, respectively, experienced adverse events (AEs) including application site reactions in 42.1%, 50.0%, and 7.4% of patients, respectively. None of the AEs were severe. CONCLUSIONS Our results showed that rotigotine was effective without major safety concerns at doses of up to 3 mg/24 h in Japanese patients with RLS.