Obstructive sleep apnoea is associated with risk factors comprising the metabolic syndrome.

Background And Objective: 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).

Methods: The study included 416 Japanese men who were diagnosed as having OSA by polysomnography.

Predicting optimal continuous positive airway pressure in Japanese patients with obstructive sleep apnoea syndrome.

Background And Objective: 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.

Methods: In 170 Japanese patients with OSA syndrome, the optimal CPAP was determined by manual titration during polysomnography.

Clinical characteristics of obesity-hypoventilation syndrome in Japan: a multi-center study.

Objective: 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).

Methods: 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.

Effects of long-term nasal continuous positive airway pressure on C-reactive protein in patients with obstructive sleep apnea syndrome.

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.

Nasal CPAP improves the quality of life and lessens the depressive symptoms in patients with obstructive sleep apnea syndrome.

Objective: 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).

Patients And Methods: 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.

[Clinical usefulness of a cardiopulmonary sleep study in patients with sleep apnea syndrome].

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.

Relationship between quality of life and mood or depression in patients with severe obstructive sleep apnea syndrome.

Study Objectives: 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.

Methods: 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.

Determinants of chronic hypercapnia in Japanese men with obstructive sleep apnea syndrome.

Study Objective: To identify the determinants of chronic hypercapnia (ie, PaCO(2), > or = 45 mm Hg) in men with obstructive sleep apnea syndrome (OSAS) without airflow obstruction.

Design: An analysis was conducted of 143 male patients with OSAS, which had been diagnosed by polysomnography (PSG), who had been referred to a university hospital. Patients were classified as hypercapnic (ie, PaCO(2), > or = 45 mm Hg) and normocapnic (ie, PaCO(2), < 45 mm Hg), and obese (ie, body mass index [BMI], > or = 30 kg/m(2)) or nonobese (ie, BMI, < 30 kg/m(2)).