Tetsuo Shimizu

Anti-NMDA-receptor antibody detected in encephalitis, schizophrenia, and narcolepsy with psychotic features

BackgroundCausative role of encephalitis in major psychotic features, dyskinesias (particularly orofacial), seizures, and autonomic and respiratory changes has been recently emphasized. These symptoms often occur in young females with ovarian teratomas and are frequently associated with serum and CSF autoantibodies to the NMDA receptor (NMDAR).MethodsThe study included a total of 61 patients from age 15 to 61 and was carried out between January 1, 2005, and Dec 31, 2010. The patients were divided into the following three clinical groups for comparison. Group A; Patients with typical clinical characteristics of anti-NMDAR encephalitis. Group B; Patients with narcolepsy with severe psychosis. Group C; Patients with schizophrenia or schizo-affective disorders.ResultsTen out of 61 cases were anti-NMDAR antibody positive in typical encephalitis cases (group A: 3 of 5 cases) and cases in a broader range of psychiatric disorders including narcolepsy (group B: 3 of 5 cases) and schizophrenia (group C: 4 of 51 cases).ConclusionIn addition to 3 typical cases, we found 7 cases with anti-NMDAR antibody associated with various psychotic and sleep symptoms, which lack any noticeable clinical signs of encephalitis (seizures and autonomic symptoms) throughout the course of the disease episodes; this result suggest that further discussion on the nosology and pathophysiology of autoimmune-mediated atypical psychosis and sleep disorders is required.

Symptomatic Narcolepsy in Patients With Neuromyelitis Optica and Multiple Sclerosis New Neurochemical and Immunological Implications

OBJECTIVE To characterize factors that contribute to symptomatic narcolepsy and excessive daytime sleepiness in neuromyelitis optica and multiple sclerosis. SETTING Japanese university hospitals. DESIGN Case study. PATIENTS Seven Japanese patients whose initial diagnoses were multiple sclerosis and who were exhibiting excessive daytime sleepiness. MAIN OUTCOME MEASURES Lesions on magnetic resonance imaging, cerebrospinal fluid hypocretin-1 levels, and serum anti-aquaporin 4 (AQP4) antibody titer. RESULTS Bilateral and symmetrical hypothalamic lesions associated with marked or moderate hypocretin deficiency were found in all 7 cases. Four of these patients met the International Classification of Sleep Disorders 2 narcolepsy criteria. Three patients, including 2 patients with narcolepsy, were seropositive for anti-AQP4 antibody and diagnosed as having neuromyelitis optica-related disorder. CONCLUSION Since AQP4 is highly expressed in the hypothalamic periventricular regions, an immune attack on AQP4 may be partially responsible for the bilateral and hypothalamic lesions and hypocretin deficiency in narcolepsy/excessive daytime sleepiness associated with autoimmune demyelinating diseases.

Cerebrospinal fluid-orexin levels and sleep attacks in four patients with Parkinson's disease

OBJECTIVES Sleep attacks (SAs) in Parkinsons disease (PD) are rare, but clinically important because they significantly impair the daily lives of patients. Causes of SAs include long-term activation of dopaminergic (especially D3) receptors. Recent studies suggest that SAs in PD may be related to impairment of hypothalamic orexin neurons, similar to narcolepsy. Whether orexin is associated with long-term activation of dopaminergic receptors remains uncertain. PATIENTS AND METHODS We measured levels of orexin in samples of spinal cerebrospinal fluid (CSF) from 25 patients with PD, including 9 with excessive daytime sleepiness and 4 with SAs. Furthermore, in the four patients with SAs, the selective dopamine D1/D2 agonist pergolide was substituted for the causative drugs with D3 stimulatory activity, and CSF-orexin levels were measured before and after switching treatment. RESULTS In the 25 patients with PD, including the 4 patients with SAs, lower CSF-orexin levels were associated with a longer disease duration, which has been linked to a higher incidence of SAs. Switching treatment to pergolide significantly increased CSF-orexin levels and completely resolved SAs in the four patients with PD. CONCLUSION Despite the small number of patients studied, our results suggest that orexin transmission is most likely involved in SAs in PD and that abrogation of D3 receptor stimulation may increase orexin and thereby inhibit SAs.

Total sleep deprivation followed by sleep phase advance and bright light therapy in drug-resistant mood disorders

BACKGROUND Drug-resistant depression is a major therapeutic issue in psychiatry and the development of non-drug therapies that treat drug-resistant depression is required. Sleep deprivation (SD) is a non-drug treatment classified as a form of chronotherapy in addition to bright light therapy (BLT) and sleep phase advance (SPA). Combined chronotherapy is hypothesized to improve drug-resistant depression. In this study, we investigated the benefits of total sleep deprivation (TSD) followed by SPA and BLT in drug-resistant depression alongside ongoing antidepressant medication and observed the added effectiveness of the combined chronotherapy. METHODS Thirteen drug-resistant inpatients affected by a major depressive episode were studied. They were treated by TSD followed by SPA (three days) and BLT (five days) with ongoing drug treatment. Effectiveness was rated using the Hamilton Rating Scale for Depression (HAM-D), the Zung Self-Rating Depression Scale (SDS), and the Visual Analogue Scale (VAS) over 3 weeks. RESULTS Significant improvements of depressive symptoms were observed in both objective mood ratings (HAM-D) and subjective mood ratings (SDS and VAS). Eight out of 13 patients maintained this responsiveness (50% or greater changes in HAM-D) across the study period. Moreover, no patients dropped out of the combined chronotherapy procedure. LIMITATIONS The study did not have a placebo group, and more subjects may be needed. CONCLUSION The trial of combined chronotherapy successfully induced rapid improvement in depressive symptoms in drug-resistant patients without early relapse or obvious side effects.

Long-term open-label study of pramipexole in patients with primary restless legs syndrome

A phase III, open-label, long-term clinical study was performed to evaluate the safety and efficacy of pramipexole in a cohort of 141 Japanese patients with primary restless legs syndrome (RLS). The patients were started on pramipexole 0.25 mg/day and were subsequently maintained on that dose or switched to 0.125, 0.5, or 0.75 mg/day to achieve optimal efficacy and tolerability. The International Restless Legs Syndrome Study Group Rating Scale for restless legs syndrome (IRLS) score improved from 22.3+/-4.7 at baseline to 11.1+/-7.7 at week 8 and 4.9+/-5.9 at week 52. IRLS responders, defined as patients whose IRLS total score decreased by > or =50% from baseline, accounted for 67.4% at week 12 and 86.6% at week 52. Over 90% of patients were Clinical Global Impression-global improvement (CGI-I) and Patient Global Impression (PGI) responders. The Pittsburgh Sleep Quality Index (PSQI) score decreased from 7.9+/-3.1 at baseline to 4.6+/-2.9 at week 52. Similarly, the Japanese version of the Epworth Sleepiness Scale score decreased from 9.3+/-5.2 to 4.9+/-3.8. Baseline IRLS score < or =20 was significantly associated with a complete IRLS response in this long-term study. Adverse events were typical of nonergot dopamine agonists, mild in intensity, and decreased in frequency as the study progressed. RLS augmentation was not observed. Pramipexole 0.25-0.75 mg/day is efficacious, safe, and well tolerated in patients with RLS. Pramipexole showed good efficacy, particularly in patients with an IRLS total score <20.

Drug interaction between St John's wort and zolpidem in healthy subjects.

What is known and objective:  St John’s wort (SJW, Hypericum perforatum) is one of the most commonly used herbal antidepressants for treatment of mild to moderate depression. SJW enhances CYP3A4 activity and alters the pharmacokinetics of CYP3A4 substrates. This study investigated the effect of SJW on the pharmacokinetics of zolpidem in healthy subjects.

Alcohol has a dose-related effect on parasympathetic nerve activity during sleep

BACKGROUND The aim of this study was to identify the acute effects of ethanol on the relationship between sleep and heart rate variability (HRV) during sleep. METHODS Ten healthy male university students were enrolled in this study. An alcoholic beverage was given to each subject at a dosage of 0 (control), 0.5 (low dose: LD), or 1.0 g (high dose: HD) of pure ethanol/kg of body weight. All experiments were performed at 3-week intervals. On the day of the experiment, a Holter electrocardiogram was attached to the subject for a 24-hour period, and the subject was instructed to drink the above-described dosage of alcoholic beverage 100 minutes before going to bed; polysomnography was then performed for 8 hours. Power spectral analysis of the HRV was performed using the maximum entropy method, and the low- (LF: 0.04 to 0.15 Hz) and high-frequency (HF: 0.15 to 0.4 Hz) components along with LF/HF ratio were calculated. RESULTS As alcohol consumption increased, the heart rate increased and the spectral power of HRV measured at each frequency range decreased. Higher doses of ethanol also increased the LF/HF ratio compared with the measured ratio of the control group. CONCLUSIONS Acute ethanol intake inhibits parasympathetic nerve activity and results in predominance of sympathetic nerve activity during sleep, in a dosage-dependent manner. The results of this study suggest that ethanol interferes with the restorative functions of sleep.

Association between heart rate variability, blood pressure and autonomic activity in cyclic alternating pattern during sleep.

STUDY OBJECTIVES Cyclic alternating pattern (CAP) is frequently followed by changes in heart rate (HR) and blood pressure (BP), but the sequential associations between CAP and autonomic nerve activity have not been studied. The study aimed to reveal the precise changes in heart rate variability (HRV) during phase A of the CAP cycle. DESIGN Polysomnography was recorded according to the CAP Atlas (Terzano, 2002), and BP and electrocardiogram were simultaneously recorded. The complex demodulation method was used for analysis of HRV and evaluation of autonomic nerve activity. SETTING Academic sleep laboratory. PARTICIPANTS Ten healthy males. MEASUREMENTS AND RESULTS The increase in HR (median [first quartile - third quartile]) for each subtype was as follows: A1, 0.64 (-0.30 to 1.69), A2, 1.44 (0.02 to 3.79), and A3, 6.24 (2.53 to 10.76) bpm (A1 vs. A2 P < 0.001, A1 vs. A3 P < 0.001, A2 vs. A3 P < 0.001). The increase in BP for each subtype was as follows: A1, 1.23 (-2.04 to 5.75), A2, 1.76 (-1.46 to 9.32), and A3, 12.51 (4.75 to 19.94) mm Hg (A1 vs. A2 P = 0.249, A1 vs. A3 P < 0.001, A2 vs. A3 P < 0.001). In all of phase A, the peak values for HR and BP appeared at 4.2 (3.5 to 5.4) and 8.4 (7.0 to 10.3) seconds, respectively, after the onset of phase A. The area under the curve for low-frequency and high-frequency amplitude significantly increased after the onset of CAP phase A (P < 0.001) and was higher in the order of subtype A3, A2, and A1 (P < 0.001). CONCLUSIONS All phase A subtypes were accompanied with increased heart rate variability, and the largest heart rate variability was seen in subtype A3, while a tendency for less heart rate variability was seen in subtype A1.

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.

Efficacy, safety and dose-response of pramipexole in Japanese patients with primary restless legs syndrome: randomized trial.

Aims: To assess the safety and efficacy of pramipexole in Japanese patients with restless legs syndrome (RLS) and to investigate factors predictive of early treatment response. Methods: Patients with primary RLS and the International Restless Legs Syndrome Study Group rating scale (IRLS) total score of >15 were randomized to receive pramipexole 0.25, 0.5 or 0.75 mg/day for 6 weeks. Results: A total of 154 patients were recruited. Following treatment, the mean adjusted change in IRLS score in the 0.25, 0.5 and 0.75 mg/day groups was –12.3, –12.5 and –11.8, respectively. The proportion of IRLS responders at week 2, when all patients were receiving pramipexole at a dose of 0.25 mg/day, was 34.0–37.7%. At 6 weeks, when the patients were on 0.25, 0.5 or 0.75 mg/day, IRLS responders defined as those having a ≧50% reduction in IRLS score accounted for 60.4, 58.5 and 49.1%, respectively. Older age above the median value (≧55 years) and low IRLS score at baseline (<21.5 points) were significantly associated with early response to low-dose pramipexole therapy. The type and frequency of adverse events were consistent with the known safety profile for dopamine agonists in RLS. Conclusions: Pramipexole at 0.25–0.75 mg/day is efficacious, safe and well tolerated in Japanese patients with primary RLS.