Toshiki Akahoshi

Nihon University, Edo, Tōkyō, Japan

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Publications (20)26.36 Total impact

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    ABSTRACT: Recent epidemiological studies have documented that depression is associated with short sleep duration, which may be interpreted as a consequence of comorbid insomnia and/or that of curtailment of time in bed (TIB). However, none of the studies examined association between depression and TIB. Here, we study TIB, short sleep duration and depression in the Japanese general adult population. Cross-sectional surveys with a face-to-face interview were conducted in 2009 as part of the Nihon University Sleep and Mental Health Epidemiology Project (NUSMEP). Data from 2532 individuals were analyzed. The Center for Epidemiologic Studies Depression Scale (CES-D) was used to assess the prevalence of depression with a cut-off point of 16. Sleep habits and sleep problems during the previous month, including bed time, getting up time, sleep duration, insomnia symptoms, and hypnotic medication use were evaluated. TIB was calculated from bed time and getting up time. The prevalence of depression identified with CES-D was 6.0% in total samples, 5.1% in men and 6.7% in women. Multiple logistic regression analysis revealed that both short sleep duration (<6 h) and short TIB (<6 h) were significantly associated with CES-D depression after adjusting for the confounding effects of sociodemographic variables, insomnia symptoms, and hypnotic medication use. We postulate that TIB, a modifiable sleep habit, may be an important target for improvement of sleep hygiene as a means of preventing depression.
    Sleep and Biological Rhythms 12/2014; · 0.76 Impact Factor
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    ABSTRACT: Sleep problems in humans have been reported to impact seriously on daily function and to have a close association with well-being. To examine the effects of individual sleep problems on physical and mental health, we conducted a nationwide epidemiological survey and examined the associations between sleep problems and perceived health status. Cross-sectional surveys with a face-to-face interview were conducted in August and September, 2009, as part of the Nihon University Sleep and Mental Health Epidemiology Project (NUSMEP). Data from 2559 people aged 20 years or older were analyzed (response rate 54.0%). Participants completed a questionnaire on perceived physical and mental health statuses, and sleep problems including the presence or absence of insomnia symptoms (i.e., difficulty initiating sleep [DIS], difficulty maintaining sleep [DMS], and early morning awakening [EMA]), excessive daytime sleepiness (EDS), poor sleep quality (PSQ), short sleep duration (SSD), and long sleep duration (LSD). The prevalence of DIS, DMS, and EMA was 14.9%, 26.6%, and 11.7%, respectively, and 32.7% of the sample reported at least one of them. At the complaint level, the prevalence of EDS, PSQ, SSD, and LSD was 1.4%, 21.7%, 4.0%, and 3.2%, respectively. Multiple logistic regression analyses revealed that DMS, PSQ, SSD, and LSD were independently associated with poor perceived physical health status; DIS, EDS, and PSQ were independently associated with poor perceived mental health status. This study has demonstrated that sleep problems have individual significance with regard to perceived physical or mental health status.
    Sleep Medicine 05/2012; 13(7):831-7. · 3.10 Impact Factor
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    ABSTRACT: Recently, the role of sleep-disordered breathing (SDB) in cardiovascular disease has attracted attention. In this study, we investigated the influence of SDB on postoperative arrhythmias after cardiac surgery. In 89 patients undergoing cardiac surgery, postoperative portable monitoring for SDB and Holter electrocardiography were performed. The primary end-points were the apnea-hypopnea index (AHI) and occurrence of arrhythmia. The secondary end-points were: (1) patient background factors; (2) average heart rate; (3) maximum heart rate (total, daytime, and nighttime); (4) minimum heart rate (total, daytime, and nighttime); (5) minimum SaO(2) during sleep; and (6) an independent predictor for arrhythmia. Twenty-six patients (29.2%) had an AHI≥15 and they were classified into the SDB group, while patients with an AHI<15 formed the non-SDB group (70.8%). Although there was no significant difference in atrial fibrillation, frequent nocturnal premature ventricular contractions were significantly more common in the SDB group (19.2%) than the non-SDB group (3.2%) (p=0.01). Maximum daytime and nighttime heart rates were also significantly higher in the SDB group. AHI was a significant predictor for frequent nocturnal premature ventricular contractions. This study showed that SDB is common among patients undergoing cardiac surgery, and that SDB might be closely associated with arrhythmia in these patients.
    Journal of Cardiology 03/2012; 60(1):61-5. · 2.57 Impact Factor
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    ABSTRACT: Airflow obstruction is the most important pathophysiologic factor in chronic obstructive pulmonary disease (COPD). Although the prevalence of airflow obstruction has been increasing worldwide, airflow obstruction is often under-recognized in clinical practice because of insufficient use of spirometry. The aim of the present study was to identify unrecognized airflow obstruction in cases with lifestyle-related diseases using a data mining system that we have developed for use with electronic medical records. Clinical, spirometric data on 27,111 patients aged 40 years or older treated during the period from January 1999 to December 2008 was retrospectively collected from the electronic medical records of the Nihon University School of Medicine clinical data warehouse. Airflow obstruction was defined according to the criteria established by the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Of the 27,111 patients, 6,098 (22.5%) showed airflow obstruction. Airflow obstruction was significantly more frequent in males, the elderly and smokers. The prevalence of airflow obstruction in patients with atherosclerosis (29.3%) was greater than that in patients with dyslipidemia (24.3%), diabetes mellitus (23.1%) or hypertension (27.1%). Only 14% of patients with airflow obstruction had a previous diagnosis of COPD. Latent COPD patients with airflow obstruction are highly prevalent, not only in those over 70 years of age with lifestyle-related diseases, but also in middle-aged patients. Spirometry should be widely used for patients with lifestyle-related diseases and a history of smoking, to effectively detect undiagnosed COPD.
    Rinsho byori. The Japanese journal of clinical pathology 02/2011; 59(2):128-33.
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    ABSTRACT: Several features of OSA syndrome suggest that it is a manifestation of the metabolic syndrome (MS). In this study, we investigated the prevalence of the MS among male Japanese patients with OSA, as well as the relationship between OSA in non-obese patients and components of the MS other than obesity (hypertension, dyslipidaemia and glucose intolerance). The study included 416 Japanese men who were diagnosed as having OSA by polysomnography. Among these, 101 non-obese patients were selected and the severity of OSA, as well as the prevalence of hypertension, dyslipidaemia and glucose intolerance, was assessed. The MS was associated with OSA in 218/416 patients (52.4%). A significant increase in the prevalence of the MS was associated with increased severity of OSA, as categorized according to AHI. In the non-obese patients with OSA (mean age 57.6 years, BMI 22.7 kg/m(2), AHI 34.3 events/h), hypertension, dyslipidaemia and glucose intolerance were identified in 70 (69.3%), 43 (42.6%) and 20 patients (19.8%), respectively. At least two of these factors were identified in 40 patients (39.6%). Non-obese patients with severe OSA had a significantly higher prevalence of two or more of these factors (33/59 patients, 55.9%). Although Asians are generally less obese than Caucasians, the prevalence of the MS was high among Japanese patients with OSA, and even among non-obese patients, OSA was associated with risk factors for the MS.
    Respirology 10/2010; 15(7):1122-6. · 3.50 Impact Factor
  • Journal of Nihon University Medical Association. 01/2010; 69(3):189-192.
  • Article: Nasal CPAP
    Journal of Nihon University Medical Association. 01/2010; 69(1):29-32.
  • Journal of Nihon University Medical Association. 01/2010; 69(3):198-202.
  • Journal of Nihon University Medical Association. 01/2010; 69(1):17-22.
  • Journal of Nihon University Medical Association. 01/2009; 68(4):240-243.
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    ABSTRACT: Several algorithms that predict the optimal CPAP have been developed for Caucasian patients with OSA syndrome, but these algorithms do not allow for racial differences in craniofacial anatomy. We investigated whether an equation that included data on craniofacial structure, physique and severity of OSA could more accurately predict the optimal CPAP for Japanese patients with OSA syndrome. In 170 Japanese patients with OSA syndrome, the optimal CPAP was determined by manual titration during polysomnography. An equation predicting the optimal pressure was derived from anthropometric, polysomnographic and cephalometric data. This equation was validated in another 110 Japanese patients with OSA syndrome. Stepwise multiple regression analysis identified AHI, BMI, mean SaO(2) and a cephalometric parameter: the angle between a line from point B to the menton (Me) and a line from Me to the hyoid bone (H) (BMeH), as independent predictors of optimal CPAP. The following equation was constructed to predict the optimal CPAP: 27.78 + (0.041 x BMeH) + (0.141 x BMI) + (0.040 x AHI) - (0.312 x mean SaO(2)). This equation accounted for 47% of the variance in optimal pressure (R(2) = 0.47, P < 0.0001). The measured optimal pressure and the pressure calculated using this equation were very similar in the other 110 patients with OSA syndrome (9.5 +/- 3.0 and 9.2 +/- 2.1 cmH(2)O, respectively). Optimal CPAP was more accurately predicted by combining a cephalometric parameter with BMI and polysomnographic data in Japanese patients with OSA, suggesting that craniofacial structure may be important in the pathogenesis of OSA syndrome among Asians.
    Respirology 12/2008; 14(2):245-50. · 3.50 Impact Factor
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    ABSTRACT: To clarify the prevalence and clinical characteristics of obesity-hypoventilation syndrome (OHS) in a large number of patients with moderate to severe obstructive sleep apnea syndrome (OSAS). Subjects comprised 611 patients with OSAS registered from 7 sleep centers and clinics and analyzed according to the definitions of the Respiratory Failure Research Group of the Japanese Ministry of Health and Welfare. Baseline characteristics, polysomnographic data during sleep, laboratory blood examinations, excessive daytime sleepiness, pulmonary functions, and arterial blood gases were compared between OHS and non-OHS patients. Determinants of daytime hypercapnia were also examined in OHS patients. OHS was identified in 55 of the 611 patients with OSAS (9%). OHS patients were younger, heavier, and more somnolent than non-OHS patients and displayed more severe OSAS, liver dysfunctions, higher total cholesterol, and impaired pulmonary function. However, these differences were resolved except for pulmonary function after correction for obesity. Daytime hypercapnia was associated with impaired pulmonary function. Percent vital capacity (%VC) was most closely correlated with PaCO2 in OHS. OHS patients display numerous abnormalities due to obesity compared with non-OHS patients. Impaired pulmonary function, particularly %VC, may play an important role in the development of daytime hypercapnia independent of obesity in OHS patients.
    Internal Medicine 02/2006; 45(20):1121-5. · 0.97 Impact Factor
  • Internal Medicine 01/2006; 45(20):1121-1125. · 0.97 Impact Factor
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    ABSTRACT: Serum levels of C-reactive protein (CRP) were measured in 96 consecutive patients with obstructive sleep apnea syndrome (OSAS) before and after nasal continous positive airway pressure treatment. CRP levels only displayed significant correlations with body mass index (BMI) before treatment. No significant changes were observed in BMI and CRP levels after 9 months of treatment. These data suggest that CRP levels in patients with OSAS may be associated with obesity rather than OSAS itself.
    Internal Medicine 09/2005; 44(8):899-900. · 0.97 Impact Factor
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    ABSTRACT: To assess changes in response to nasal continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea syndrome (OSAS) concerning excessive daytime sleepiness (EDS), depressive state, and quality of life (QOL). We assessed for EDS using the Epworth sleepiness scale (ESS), for mood using The Zung self-depression scale (SDS), and for QOL using Short-Form 36 (SF-36) in 132 patients with obstructive sleep apnea syndrome (OSAS) and control subjects. Patients had severe OSAS (apnea-hypopnea index, 59.4+/-23.8/h) and were more hypersomnolent and depressed, and had poorer QOL than 38 age- and gender-matched controls. Before treatment most QOL domains in the SF-36 were significantly associated with patients' SDS scores. With nasal CPAP, ESS and SDS scores were respectively decreased from 9.7+/-4.5 to 4.0+/-2.4 (p<0.0001) and from 49.2+/-10.4 to 45.1+/-9.6 (p<0.0005). Total SF-36 score and scores for seven of eight domains were increased significantly with treatment. Thus, nasal CPAP lessens EDS and depression, and improves QOL, in patients with severe OSAS. Further, magnitudes of changes in total SF-36 scores and in five of eight domains correlated significantly with magnitude of change in SDS score upon nasal CPAP treatment. No relationship was evident between treatment-associated score changes in SF-36 domains and ESS score change. Although patients with severe OSAS have poorer QOL than control subjects, nasal CPAP appears to improve QOL by alleviating depression.
    Internal Medicine 06/2005; 44(5):422-7. · 0.97 Impact Factor
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    ABSTRACT: Although polysomnography is indispensable in the diagnosis of sleep apnea syndrome (SAS), a common disease in Japan, it is a time-consuming procedure. We therefore assessed the clinical usefulness of a cardiopulmonary sleep study (CPSS), which monitors indices of respiratory and circulatory kinetics during sleep. Of ninety male patients (50 +/- 11 years old, BMI: 27 +/- 4), those with apnea indices (AI) > 5, as determined using an apnomonitor, underwent CPSS with a Night Watch System. Sixty-nine patients with indications for nasal CPAP (NCPAP) therapy underwent overnight CPSS and the optimum pressure was determined. AI was 31 +/- 17, whereas CPSS showed an apnea-hypopnea index of 49 +/- 24, a mean SaO2 of 93 +/- 3%, and a minimum SaO2 of 71 +/- 11%, indicating severe OSAS. The mean optimum pressure was 10 +/- 2 cm H2O, and the compliance was 86%, which was comparatively good. As CPSS can be performed on many patients in a short time, it may be useful for the early diagnosis and initial treatment of SAS.
    Nihon Kokyūki Gakkai zasshi = the journal of the Japanese Respiratory Society. 11/2002; 40(11):845-50.
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    ABSTRACT: To assess the quality of life (QOL) in patients with severe obstructive sleep apnea (OSAS), and the relationship between the QOL and severity of OSAS, excessive daytime sleepiness (EDS), and mood. Sixty patients with OSAS and 34 normal control subjects were assessed for QOL using the Medical Outcomes Study Short-Form 36 Health Survey questionnaire (SF-36), for EDS using the Epworth sleepiness scale (ESS), and for mood using the Zung self-rated depression scale (SDS). The associations between each domain and the total score on the SF-36 and the baseline characteristics, polysomnographic parameters, ESS score, and SDS score were examined by simple regression analysis and stepwise multiple regression analysis. Six of eight domains and the total score on the SF-36 were significantly lower than those in the control subjects. The ESS and SDS scores were also more impaired in the patients than in the control subjects. There was no relationship between each domain on the SF-36 and the severity of OSAS and ESS score. Five of eight domains and the total score on the SF-36 were significantly correlated with the SDS score. Stepwise multiple regression analysis selected three variables, the SDS score (partial R(2) = 0.505), the lowest arterial oxygen saturation during sleep (partial R(2) = 0.064), and ESS score (partial R(2) = 0.053), as independent factors for predicting the total score on the SF-36. These three variables accounted for 62.2% of the total variance in the total score on SF-36 (R(2) = 0.622, p < 0.0001) The QOL of patients with severe OSAS was decreased compared with normal control subjects. The QOL of patients was strongly correlated with the depression scale on simple regression analysis. However, EDS score and oxygen desaturation during sleep also affected the QOL, although the magnitude of its effect was small.
    Chest 09/2002; 122(3):861-5. · 7.13 Impact Factor
  • Masui. The Japanese journal of anesthesiology 01/2002; 50 Suppl:S45-50.
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    ABSTRACT: To assess the acute effects of nasal continuous positive airway pressure (CPAP) on the 24-hour blood pressure and the secretion of catecholamines in urine and plasma, we investigated the changes in the 24-hour blood pressure and urinary and plasma concentrations of epinephrine (E) and norepinephrine (NE) in 26 men with obstructive sleep apnea (OSA) with and without nasal CPAP. Nasal CPAP resulted in significant decreases in the daytime diastolic pressure (from 86 +/-16 mmHg to 83+/-12 mmHg), the nighttime diastolic pressure (from 81+/-12 mmHg to 77+/-9 mmHg) and the nighttime systolic pressures (from 125+/-15 mmHg to 120+/-10 mmHg). There was no significant difference between patients with and without CPAP in the daytime or nighttime urinary E level, but patients who received CPAP showed a significant decrease in daytime urinary NE level (from 156+/-112 microg/14h to 119+/-101 microg/14h) and nighttime urinary NE level (from 143+/-91 microg/10h to 112+/-65 microg/10h). The morning plasma level of NE also decreased (from 371+/-181 pg/ml to 273 +/-148 pg/ml) in patients who received nasal CPAP (p<0.02), but the plasma level of E remained unchanged. There were no correlations between PSG parameters and the reductions in blood pressure and the catecholamine levels induced by nasal CPAP. These findings suggest that OSA contributes, at least in part, to the development of systemic hypertension by increasing sympathetic nervous activity.
    Internal Medicine 01/1999; 37(12):1009-13. · 0.97 Impact Factor
  • Internal Medicine 01/1998; 37(12):1009-1013. · 0.97 Impact Factor