Fuat Özgen

Sleep stage and obstructive apneaic epoch classification using single-lead ECG

BackgroundPolysomnography (PSG) is used to define physiological sleep and different physiological sleep stages, to assess sleep quality and diagnose many types of sleep disorders such as obstructive sleep apnea. However, PSG requires not only the connection of various sensors and electrodes to the subject but also spending the night in a bed that is different from the subjects own bed. This study is designed to investigate the feasibility of automatic classification of sleep stages and obstructive apneaic epochs using only the features derived from a single-lead electrocardiography (ECG) signal.MethodsFor this purpose, PSG recordings (ECG included) were obtained during the nights sleep (mean duration 7 hours) of 17 subjects (5 men) with ages between 26 and 67. Based on these recordings, sleep experts performed sleep scoring for each subject. This study consisted of the following steps: (1) Visual inspection of ECG data corresponding to each 30-second epoch, and selection of epochs with relatively clean signals, (2) beat-to-beat interval (RR interval) computation using an R-peak detection algorithm, (3) feature extraction from RR interval values, and (4) classification of sleep stages (or obstructive apneaic periods) using one-versus-rest approach. The features used in the study were the median value, the difference between the 75 and 25 percentile values, and mean absolute deviations of the RR intervals computed for each epoch. The k-nearest-neighbor (kNN), quadratic discriminant analysis (QDA), and support vector machines (SVM) methods were used as the classification tools. In the testing procedure 10-fold cross-validation was employed.ResultsQDA and SVM performed similarly well and significantly better than kNN for both sleep stage and apneaic epoch classification studies. The classification accuracy rates were between 80 and 90% for the stages other than non-rapid-eye-movement stage 2. The accuracies were 60 or 70% for that specific stage. In five obstructive sleep apnea (OSA) patients, the accurate apneaic epoch detection rates were over 89% for QDA and SVM.ConclusionThis study, in general, showed that RR-interval based classification, which requires only single-lead ECG, is feasible for sleep stage and apneaic epoch determination and can pave the road for a simple automatic classification system suitable for home-use.

Mirtazapine augmentation in depressed patients with sexual dysfunction due to selective serotonin reuptake inhibitors

To evaluate the effect of mirtazapine augmentation in patients with sexual dysfunction induced by current selective serotonin reuptake inhibitor (SSRI) treatment.

Impact of endoscopic sinus surgery on sleep quality in patients with chronic nasal obstruction due to nasal polyposis.

Objective: The aim of this study was to investigate the effect of endoscopic sinus surgery on sleep quality in a patient group who has chronic nasal obstruction resulting from nasal polyposis. Methods: Twenty-seven patients with nasal polyposis, filling at least 50% of each nasal passage, were enrolled in the study. Assessment of nasal patency was determined by nasal endoscopy and acoustic rhinometry. All patients underwent endoscopic sinus surgery with polypectomy. Sleep quality was evaluated, using visual analog scale, Epworth sleepiness scale, and polysomnography before and 3 months after the surgery. Results: Nasal resistance decreased significantly after the surgery (P < 0.01). Snoring scores were significantly improved postoperatively (P < 0.01) and completely disappeared in 9 of 27 patients. A significant improvement occurred in mean daytime sleepiness scores in the postoperative period (4.14) as compared with the preoperative values (9.44; P < 0.01). There was no significant difference between preoperative (6.85) and postoperative (5.53) mean values of apnea-hypopnea index (P = 0.55). Conclusions: Endoscopic sinus surgery with polypectomy significantly improves sleep quality, including snoring and daytime sleepiness in patients with chronic nasal obstruction due to nasal polyposis. However, it has a limited benefit on apnea-hypopnea index scores.

Lingual tonsil hypertrophy producing obstructive sleep apnea.

The hypertrophy of the lingual tonsil is a rare occurrence in adults. This disorder may cause obstructive sleep apnea (OSA) and also may lead to a life‐threatening obstruction of the upper airway. Diagnosis of lingual tonsil hypertrophy in patients with OSA requires a careful examination by advanced technologic methods. The sleep apnea is successfully treated by lingual tonsillectomy, with or without tracheotomy.

The association between serum levels of neopterin and number of depressive episodes of major depression

BACKGROUND There is an interaction between the immune system and the central nervous system by means of hormones, peptides, and neurotransmitters. The aims of the present study were to determine whether the serum neopterin levels in patients with major depression (MD) differ from a healthy control group and to investigate the relationship between previous MD episodes and serum neopterin levels. METHODS Thirty patients who were admitted to the GATA Psychiatry Outpatient Clinics and were diagnosed with MD according to DSM-IV, and who agreed to participate in the study, were included in the study. Twenty-six healthy volunteers matched for age, gender, and level of education who agreed to participate in the study were served as controls. Peripheral venous blood samples were obtained from the patients and the control group for complete blood count, routine biochemistry, and the detection of serum neopterin levels. The analyses were performed in the laboratory of the GATA Department of Biochemistry. RESULTS There was no significant difference between the MD group and the healthy controls with respect to age, level of education, smoking, and gender. Serum neopterin levels of the MD group who had experienced two or more episodes were higher than the first-episode group and the control group. Age of onset and the number of previous episodes had an independent impact on serum neopterin levels in MD patients, while smoking did not show any effect. CONCLUSION In the present study, the neopterin levels of patients who had experienced two or more episodes were higher than the first-episode depressive group and healthy control group. It was also found that the number of previous depressive episodes and the ages of the MD cases had an independent effect on serum neopterin levels.

Evaluation of periodic leg movements and associated transcranial magnetic stimulation parameters in restless legs syndrome.

Restless legs syndrome (RLS), a sensorimotor disorder characterized by unpleasant sensations commonly localized in the legs, is frequently associated with periodic limb movements (PLMs) during sleep. We investigated the role of transcranial magnetic stimulation (TMS) and cortical silent period (CSP) duration as diagnostic and monitoring tools in 20 patients with primary RLS before and after 1 month of treatment and also studied 15 normal age‐ and gender‐matched subjects. Polysomnographic assessment was undertaken and the PLM index determined in 17 of the 20 patients. We also studied the correlation between sleep efficiency index and CSP duration because of the increasing severity of the sleep disturbance and PLMs in patients with RLS. Our results demonstrate that the duration of the CSP was reduced in patients with RLS, and that dopaminergic treatment normalized this duration. There was no correlation between the PLM index and CSP duration. It may be speculated that PLMs and the CSP are due to different inhibitory mechanisms and they may be used separately as diagnostic and monitoring tools in patients with primary RLS. Muscle Nerve, 2005

Polysomnography in patients with post-traumatic stress disorder

Aims:  The purpose of the present study was to investigate sleep structure in post‐traumatic stress disorder (PTSD) patients with and without any psychiatric comorbidities. The relationship between sleep variables and measurements of clinical symptom severity were also investigated.

The upper airway evaluation of habitual snorers and obstructive sleep apnea patients.

Objective: To investigate the relationship between the Apnea Hypopnea Index (AHI) and upper airway examination findings of habitual snorers and obstructive sleep apnea (OSA) patients. Materials and Methods: This study included 264 patients whose tonsils were evaluated in 4 grades. The Mallampati classification was used to determine the relationship between tongue and palate. All patients performed the Müller maneuver in a sitting position. The Fujita classification was used to define the type of obstruction. All patients had polysomnography and were divided into 4 groups according to AHI. Statistical analysis was performed to evaluate the relationship between examination findings and AHI. Results: Of the patients, 133 (50.4%) were habitual snorers, 66 (25%) were mild OSA, 40 (15.2%) were moderate OSA and 25 (9.5%) were severe OSA patients. There was a positive correlation between neck circumference, BMI and AHI in males (p < 0.001). There was a significant difference between patient groups according to Mallampati classification, collapse at the velopharyngeal level and hypopharyngeal level and Fujita classification (all p < 0.001). There were significant relationships between tonsil size, Fujita classification, Mallampati classification, collapse ratios and AHI. Conclusion: We saw that hypopharyngeal area often contributes to obstruction and some examination methods correlate more with AHI. This can aid sleep physicians in the evaluation of OSA patients.

Quality of sexual life in men with obstructive sleep apnoea

The study investigated the quality of sexual life of male obstructive sleep apnoea patients. Apnoea and non-apnoea participants were assessed with Golombok Rust Inventory of Sexual Satisfaction (GRISS) and Structured Clinical Interview for DSM-IV (SCID) before the sleep test. Folicule Stimulating Hormone (FSH), Luteinising Hormone (LH), prolactin, testosterone and oestrogen levels were also evaluated. The apnoea group had a higher BMI and lower LH and testosterone levels than the non-apnoea group. There were no differences between the apnoea, non-apnoea groups and within the apnoea groups (mild, moderate and high apnoea) in terms of sexual satisfaction. Although there was a change in the hormonal levels of obstructive sleep apnoea patients, the sexual life of apnoea patients was not affected at the clinical level.

Validation of the STOP-Bang Questionnaire: an Obstructive Sleep Apnoea Screening Tool in Turkish Population

Son yıllarda yayınlanan makaleler incelendiğinde, anestezistlerin preoperatif muayene sırasında her hastayı obstrüktif uyku apnesi (OUA) olasılığı açısından değerlendirmesinin gerekli olduğu anlaşılmaktadır. Bu gereklilik başlıca iki nedene dayanır; ilki, OUA hastalarının %80-90’ının tanı konmamış durumda olmalarıdır (1). İkinci neden ise, Amerikan Anestezistler Birliği’nin (ASA) 2006’da yayımladığı bir kılavuzla, cerrahi hastalara preoperatif dönemde OUA açısından tarama yapılmasını önermiş olmasıdır (2). Preoperatif dönemde kullanılacak uygun bir tarama ile OUA olasılığı yüksek olan hastalar belirlenip, anestezistlerin peroperatif dönemde karşı karşıya kalabilecekleri riskler en aza indirilebilir.