
Tetsuo ShimizuAkita University · Department of Neuropsychiatry
Tetsuo Shimizu
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290
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Introduction
Additional affiliations
November 1983 - present
Akita University Graduate Schhol of Medicine
Position
- Professor (Full)
Publications
Publications (290)
Dyspnea is a generalized subjective symptom of discomfort and effort during breathing. Dyspnea is a subjective sensation, and there are various expressions of dyspnea such as a feeling of insufficient air, a feeling of effort in respiratory movements, a feeling of tightness in the chest, and a feeling of suffocation. Dyspnea is not limited to respi...
Pneumonia is an acute inflammation of the lung parenchyma (alveolus) caused by infection with a variety of pathogenic microorganisms. Bacterial pneumonia is the most frequent.
Background
Neuromyelitis optica spectrum disorder (NMOSD) diagnostic criteria for inflammatory demyelinating central nervous system diseases included symptomatic narcolepsy; however, no relevant case‐control studies exist. We aimed to examine the relationship among cerebrospinal fluid orexin‐A (CSF‐OX) levels, cataplexy and diencephalic syndrome; d...
Cataplexy is a sudden drop of antigravity-muscle tone triggered most often by positive emotional factors, which is one of the major symptoms of narcolepsy. Cataplexy has been treated pharmacologically, most often with tricyclic antidepressants. Even though tricyclic antidepressants are effective in reducing sleep paralysis and hypnagogic hallucinat...
Purpose
Multiple sleep latency test (MSLT) is performed as objective assessment of sleepiness, on the following day after polysomnography (PSG). In most clinics, patients are required to stay for 2 days. However, if patients have chronic sleep debt before the examination, even if they get adequate nocturnal sleep during the initial PSG, their sleep...
Study objectives:
Niemann-Pick type C (NPC) is an autosomal recessive and congenital neurological disorder characterized by the accumulation of cholesterol and glycosphingolipids. Symptoms include hepatosplenomegaly, vertical supranuclear saccadic palsy, ataxia, dystonia, and dementia. Some cases frequently display narcolepsy-like symptoms, includ...
Recently developed melatonin receptor agonists are expected to be effective for delayed sleep-wake phase disorder (DSWPD). To date, however, no study has described the effect of melatonin receptor agonists on DSWPD. We report the case of a 15-year-old girl with DSWPD who was successfully treated with ramelteon 4 mg at 7 PM. DSWPD symptoms were reso...
Objective
The objective of this study was to investigate the relationship between the serum concentration of clozapine (C-CLZ), Ndesmethylclozapine (N-CLZ) and the daily dose of CLZ (D-CLZ), and the relationships among CLZ and electroencephalogram (EEG) abnormalities.
Methods
Twenty-eight patients were recruited to this study, but 8 patients were...
Purpose
The core features of dementia with Lewy bodies (DLB) are cognitive fluctuations, visual hallucinations, and parkinsonian symptoms. Although there have been several reports on the efficacy of treatments for psychotic symptoms in patients with DLB, little is known regarding the treatment effects of aripiprazole. The aim of this study was to e...
Public concern has been growing over severe adverse events caused by human papillomavirus (HPV) vaccination. Some patients also exhibited sleep disorders. We investigated their symptoms, clinical examinations and cerebrospinal fluid orexin (hypocretin) levels. The subjects were 6 patients with hypersomnolence after HPV vaccination. Since all of the...
Objective
Gabapentin and its prodrug are candidate therapeutic agents for akathisia. An open-label pilot study was conducted to investigate the therapeutic potential of gabapentin enacarbil (GE) for akathisia.
Methods
In an open-labeled investigator-initiated clinical trial, nine outpatients with antipsychotics-induced akathisia were administered...
Purpose
The efficacy of inpatient phase-advance therapy among patients with delayed sleep–wake phase disorder (DSWPD) has not been adequately investigated because response rates are considered low. We aimed to examine the efficacy of such treatment in this patient population.
Patients and methods
The present retrospective study included data from...
Purpose
Symptomatic narcolepsy is characterized as low orexin (hypocretin) levels (≤ 110 pg/ml) due to neurological diseases. However, we have experienced the cases that show symptoms similar to narcolepsy, complaining of pathological sleepiness even in cases with intermediate orexin levels (110–200 pg/ml). Therefore, we reevaluated the previously...
Essential hypersomnia (EHS) is a lifelong disorder characterized by excessive daytime sleepiness without cataplexy. EHS is associated with human leukocyte antigen (HLA)-DQB1*06:02, similar to narcolepsy with cataplexy (narcolepsy). Previous studies suggest that DQB1*06:02-positive and -negative EHS are different in terms of their clinical features...
The management of clozapine (CLZ)-induced adverse events affects patient prognoses. Akathisia is a relatively rare adverse event related to CLZ administration and thus the management of this syndrome is not well established. Here, we report a case of treatment-resistant schizophrenia wherein CLZ-induced akathisia was successfully managed with gabap...
Orexin (Hypocretin) is a neuropeptide that plays an important role in arousal state and food intake, and was discovered in 1998 (1) (2). Cerebrospinal fluid (CSF) Orexin‐A (Hypocretin‐1) level is a biomarker used to diagnose narcolepsy type 1 (NT1) (3).
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The management of clozapine (CLZ)-induced adverse events affects patient prognoses. Akathisia is a relatively rare adverse event related to CLZ administration and thus the management of this syndrome is not well established. Here, we report a case of treatment-resistant schizophrenia wherein CLZ-induced akathisia was successfully managed with gabap...
Objective
Involvement of the hypothalamus is rare in patients with systemic lupus erythematosus (SLE). In this study, we measured cerebrospinal fluid (CSF) orexin-A levels in SLE patients with hypothalamic lesions to investigate whether the orexin system plays a role in SLE patients with hypothalamic lesions who present with excessive daytime sleep...
Background
Patients with anorexia nervosa (AN) often present with pancytopenia. In most cases described in the literature, AN with pancytopenia demonstrates gelatinous marrow transformation (GMT), which is a typical bone marrow feature of malnutrition. Differentiation of AN-associated pancytopenia from other types of pancytopenia, especially idiopa...
Purpose
Venous thromboembolism (VTE) is the combination of pulmonary embolism (PE) and deep vein thrombosis. In recent years, VTE has been gaining attention in the field of psychiatry as it can cause sudden deaths in patients hospitalized in psychiatric departments. The purpose of this study was to investigate the incidence of VTE in psychiatric in...
Significance
Narcolepsy is a chronic neurological disorder that severely affects the day-to-day life and general well-being of the affected individuals. Unfortunately, treatments available to date are symptomatic therapies with an array of adverse effects. Animal studies showed that orexin peptide can be a mechanistic therapy to treat narcolepsy. H...
Objectives
Delayed sleep phase syndrome (DSPS) is a chronic dysfunction of circadian rhythm of the subject that impairs functioning in social, occupational, or other spheres. High rate of depression is found among DSPS patients. Aripiprazole (APZ), a second-generation antipsychotic, is effective in treatment of depression as well as schizophrenia....
[This corrects the article on p. 451 in vol. 14, PMID: 29445282.].
Introduction
Short sleepers had been defined to obtain less than 5 hours of sleep per night on average without sleep/wake complaints and obvious daytime dysfunction (ICSD-2). Various studies have linked short sleep duration with metabolic, cardiovascular, and other forms of medical morbidity. However, these studies are typically unable to distingui...
Introduction
In recent times, attention has been paid to the relationship between developmental disorders such as attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), and sleep disorders. Previously, we had been focus on the problems of nocturnal sleep, such as insomnia and circadian rhythm disorder in ASD patients. R...
Introduction
We have been studying sleep facilitation of chloride spring and artificially carbonated spring (ACS). ACS are known to increase peripheral blood flow. We concluded that ACS caused great body temperature change and promoted sleep. On the other hand, ACS are also known to have an effect on the autonomic nervous system, but no one examine...
Purpose
Myotonic dystrophy type 1 (DM1) is often characterized by excessive daytime sleepiness (EDS) and sleep-onset rapid eye movement periods caused by muscleblind-like protein 2. The EDS tends to persist even after treatment of sleep apnea. We measured the cerebrospinal fluid (CSF) orexin levels in DM1 patients with EDS and compared the clinical...
Some epidemiological studies with a large number of subjects, like a national health study, reported that precarious employment was associated with increased depressive symptoms, but this hypothesis may not be applicable to precarious workers of all industry types. We examined the association between precarious employment and depressive symptoms in...
Hypnotics may be used by athletes to avoid sleep disturbance or insufficient sleep the night before sports events. However, in the past, taking hypnotics for sleep disturbances resulted in an unsuccessful attempt due to residual effects. The purpose of this study is to assess the residual effects of eszopiclone (2 mg), one of the non-benzodiazepine...
Next-day residual effects are a common problem with current hypnotics. The purpose of the present study was to evaluate the residual effects of eszopiclone on the physical and cognitive functions of healthy elderly people in the early morning and the day following drug administration. Four men and six women aged 63–72 years were administered eszopi...
Introduction
Next-day residual effects are a common problem with current hypnotic agents. The purpose of the present study was to evaluate the residual effects of the new agent - suvorexant that doesn’t have the muscle relaxation effect - on the physical and cognitive functions of healthy elderly people in the early morning and the day following dr...
Introduction
Recently we attempted an ECG recording in intact freely-behaving mice by using a plate sensor that has multiple (15) gold-plated electrodes, on which mice can walk around freely, without the use of tether or telemetry system. Although the electrodes are a kind of dry electrode, we found that the ECG plate sensor detects ECG from mouse’...
Introduction
Delayed sleep phase disorder (DSPD) typically begins in the second decade of life or earlier. DSPD comprises a persistent or recurrent pattern of sleep disturbances, sleep disruption that leads to insomnia and/or excessive daytime sleepiness, and impaired functioning in social, occupational, or other spheres. Three techniques are typic...
Introduction
Next-day residual effects are a common problem with current hypnotics. The purpose of the present study was to evaluate the residual effects of the eszopiclone on the physical and cognitive functions of healthy elderly people in the early morning and the day following drug administration.
Methods
Four men and six women aged 63–72 year...
Introduction
The symptoms of narcolepsy can occur during the course of other neurological conditions. Inherited disorders, tumors and demyelinating diseases were the three most frequent causes for symptomatic narcolepsy. Among inherited disorders, Niemann-Pick type C (NPC), Myotonic dystrophy type 1 and Prader-Willi syndrome were major three disord...
Introduction
Clozapine is one of the most effective drugs for the treatment resistant schizophrenia (TRS). It was reported that modified electroconvulsive therapy (mECT) may be an effective clozapine augmentation strategy in TRS.
Objective
The objective of this study was to investigate the influence of clozapine to mECT in the TRS.
Methods
Forty-...
The symptoms of catatonia have been reported to be similar to the initial symptoms of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Subsequently, this autoimmune limbic encephalitis has been noticed by many psychiatrists. For a differential diagnosis of catatonic state, it is important to detect anti-NMDAR encephalitis. This encephalitis...
Background:
Bilateral paramedian thalamic infarctions (BPTIs) due to artery of Percheron occlusion are known to cause hypersomnia. However, the role of hypocretin-1, a wake-promoting peptide that is located at the lateral hypothalamus, in hypersomnia in these patients remains unclear.
Methods:
To clarify the role of hypocretin-1 in hypersomnia i...
The aim of this study was to clarify how painful physical symptoms affect treatment outcomes in patients with melancholic major depressive disorder. The subjects comprised 100 consecutive Japanese outpatients with melancholic major depressive disorder who visited our clinic from October 2011 to October 2014. All subjects were interviewed for Diagno...
Objective
Dementia with lewy bodies (DLB) is commonly considered the second most common form of dementia. The purpose of this study is to investigate the treatment effects of aripiprazole in patients with DLB.
Methods
Eleven patients who had meet the criteria for DLB participated in this study. The presence of psychotic symptoms was confirmed by s...
Prader-Willi syndrome is a congenital neurodevelopmental disorder resulting from deletion of the paternal copies of genes within the chromosome region 15q11-q13. Patients with Prader-Willi syndrome often exhibit excessive daytime sleepiness, excessive appetite, and obesity. As is the case in narcolepsy, orexin (hypocretin) may be responsible for th...
The symptoms of narcolepsy can occur during the course of other neurological conditions (i.e., symptomatic narcolepsy). We define symptomatic narcolepsy as cases that meet the International Sleep Disorders Narcolepsy Criteria, which are also associated with a significant underlying neurological disorder that accounts for excessive daytime sleepines...
The symptoms of narcolepsy can occur during the course of other neurological conditions (i.e. symptomatic narcolepsy). We define symptomatic narcolepsy as cases that meet the International Sleep Disorders Narcolepsy Criteria, which are also associated with a significant underlying neurological disorder that accounts for excessive daytime sleepiness...
Narcolepsy without cataplexy (NA w/o CA) (narcolepsy type 2) is a lifelong disorder characterized by excessive daytime sleepiness and rapid eye movement (REM) sleep abnormalities, but no cataplexy. In the present study, we examined the human leukocyte antigen HLA-DQB1 in 160 Japanese patients with NA w/o CA and 1,418 control subjects. Frequencies o...
With current hypnotic agents, next-day residual effects are a common problem. The purpose of the present study was to evaluate the residual effects of the commercially available hypnotics - zolpidem, triazolam, and rilmazafone - on the physical and cognitive functions of healthy elderly people in the early morning and the day following drug adminis...
Excessive daytime sleepiness (EDS) is rather common in the elderly, however, it does not mean that EDS is physiological in that population. EDS may be caused by sleep related breathing disorder (SRBD), which is very popular among elderly people. Also EDS of narcolepsy is a life-long symptom. Recently, many reports come out indicating that EDS would...
Insulinoma is a rare endocrine tumor that can cause a wide variety of symptoms, including abnormal nocturnal behavior. We report on 3 patients with insulinoma who presented with abnormal nocturnal behavior and injury during sleep, which simulated rapid eye movement (REM) sleep behavior disorder (RBD). In case 1, the fasting glucose level was 15 mg/...
Etiology of narcolepsy-cataplexy involves multiple genetic and environmental factors. While the human leukocyte antigen (HLA)-DRB1*15:01-DQB1*06:02 haplotype is strongly associated with narcolepsy, it is not sufficient for disease development. To identify additional, non-HLA susceptibility genes, we conducted a genome-wide association study (GWAS)...
We studied the relationship of orexin (hypocretin) system and astrocyte activation in hypersomnolence symptom (HS) in Parkinson's disease (PD). In a total of 30 subjects, including five PD patients with HS, eight PD patients without HS, eight patients with narcolepsy, and nine control subjects, orexin and glial fibrillary acidic protein (GFAP) as w...
Introduction
Clozapine-induced electroencephalography (EEG) abnormalities are common. It has been reported that clozapine-induced EEG abnormalities occur in a dose-dependent manner and correlate with the serum concentration of clozapine (C-CLZ). However, the oppositional results were also reported.
Objectives
The objective of this study was to inv...
A simplified diagnostic/monitoring instrument for use in primary screening for sleep-disordered breathing (SDB) has been desired. This study was designed to assess the validity of a newly developed piezoelectric sensor as a simple and noninvasive tool for primary screening for sleep-disordered breathing. Forty-three consecutive patients suspected o...
The symptoms of malignant (lethal) catatonia has been reported similar to initial symptoms of anti-NMDAR encephalitis. Subsequently, this autoimmune limbic encephalitis has been noticed in many psychiatrists. We have experienced several cases with malignant catatonia having anti-NMDAR antibody without clinical signs of encephalitis. Thereafter, we...
Purpose
We describe electroencephalography (EEG) abnormalities and seizures associated with clozapine treatment in Japanese patients with schizophrenia and retrospectively compare EEG results and total Positive and Negative Syndrome Scale (PANSS [T]) scores before and after treatment.
Methods
Twenty-six patients with treatment-resistant schizophre...
Narcolepsy, a sleep disorder characterized by excessive daytime sleepiness, cataplexy and rapid eye movement sleep abnormalities,
is tightly associated with human leukocyte antigen HLA-DQB1*06:02. DQB1*06:02 is common in the general population (10–30%); therefore, additional genetic factors are needed for the development of narcolepsy.
In the prese...
Sleep and behavioral monitoring of young mice is necessary for understating the progress of these symptoms in congenital and acquired diseases associated with sleep and movement disorders. In the current study, we have developed a non-invasive sleep monitoring system that identifies wake and sleep of newborn mice using a simple piezoelectric transd...
The purposes of this study were to investigate the validity and reliability of the Japanese version of Horne and Östberg's Morningness-Eveningness Questionnaire (MEQ) and the characteristics of chronotype using other questionnaires and wrist actigraphy in healthy young subjects. The participants were 102 university student volunteers. The participa...
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.
Polysomnography was recorded acc...
The aim of this study was to compare the simultaneous analysis of sleep using wrist actigraphy and waist actigraphy in healthy young subjects. We studied 102 healthy university students (55 men, 47 women), aged 18–40 years. Participants were instructed to continue normal life activities and sleep–wake rhythms for 7 consecutive nights without extrao...
We aimed to ascertain the efficacy and safety of transdermal rotigotine (2 and 3mg/24h) in Japanese patients with restless legs syndrome (RLS).
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 13weeks. The primary endpoint was the...
The aim of this study was to determine the characteristics of drug adherence in antidepressant-treated versus antidepressant-naïve patients using Drug Attitude Inventory (DAI)-10 scores for nonadherence, to examine the contribution of patient variables such as age, gender, education, prescription contents, side effects, and type of depression (mela...
Objectives:
To evaluate the efficacy and dose-response effect of eszopiclone on sleep latency and sleep maintenance in Japanese patients with primary insomnia.
Methods:
In this randomized, double-blind, five-way crossover study, 72 patients received placebo, eszopiclone 1mg, 2mg, and 3mg, and zolpidem 10mg in random order for two consecutive nig...
This study aimed to reveal the characteristics of prescribing hypnotics at Japanese medical institutions, with data on medical payments from 4 large-scale Japanese health insurance organizations with almost 320 000 members. The study targeted the data from 4807 patients, aged 20 to 74 years, who were prescribed hypnotics during a 3-month surveillan...
This study aimed to examine the prevalence of depressive symptoms and related factors in Japan. For this purpose, a questionnaire including the Center for Epidemiologic Studies Depression Scale (CES-D) was administered to employees from Akita prefecture, Japan. The cutoff point for CES-D scores was 16 or above (high scorers). We analyzed the result...
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 chronothe...
Residual symptoms are common in depression, and their presence is associated with poorer clinical outcomes of depression. We conducted a case series study of first-onset major depression to elucidate the clinical course of residual insomnia and examine the relationship between residual insomnia and recurrence of depression. Subjects were 128 patien...
There have been a lot of studies on the relationship between insomnia and depression, however, only a little is elucidated about the relationship between sleep habits and depression. In modern societies, long working hours, shift-work, and late bed-time are quite prevalent. However, based on the findings of a few recent papers, it is suggested that...
Causative 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).
The study inc...
BACKGROUND: The causative 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...