Three-dimensional Morphological Analyses of Positional Dependence in Patients with Obstructive Sleep Apnea Syndrome

Positional supine obstructive sleep apnea syndrome (OSAS) characterizes a subgroup of patients suffering from OSAS. Several devices designed to limit supine position have been developed, but evidences of their efficacy and safety are lacking. It is unclear whether a neck-worn vibrating device could induce positional change in patients with positional OSAS. We evaluated the efficacy of a neck-worn device to induce supine avoidance positional feedback over a short-term trial in OSAS patients and its impact on sleep quality and polysomnographyc indexes. Twenty patients with positional apneas/hypopneas were prospectively studied. Baseline characteristics of daytime somnolence and risk of sleep apnea were screened and the efficacy of a 3-day trial of supine-avoidance therapy by vibrotactile neck worn device assessed by reporting the self-perceived change in quality of sleep and performing cardio-respiratory polysomnography. Comparison between baseline and treatment results was performed. The neck device produced a reduction in overall apnea-hypopnea index (AHI) (mean AHI pre =16.8/h and post =4.4/h, P<0.0001), oxygen desaturation (pre =13.7/h and post =3.8/h, P<0.0001) and Respiratory Disturbance Indexes (RDI) (20.0/h vs. 5.2/h; P<0.0001).The time spent in supine position decreased from 62.1% to 33.7% of the total (P<0.001). However, the impact on the perceived quality of sleep was unpredictable. The neck position therapy device is effective in restricting supine sleep, improving AHI and related polysomnographic indexes. However, at least in a short-term trial, it seems unable to improve the patient's sleep quality.

AIM:We aimed to compare the clinical, epidemiological, and polysomnographic features of rapid eye movement (REM)-dependent obstructive sleep apnea syndrome (OSAS) and positional OSAS which are two separate clinical entities.METHODS:Between January 2014 and December 2015, at the Akdeniz University Medical Faculty Hospital, patients who were diagnosed REM-dependent and positional OSAS with polysomnography were retrospectively studied.RESULTS:In this study, 1727 patients were screened consecutively. Five hundred and eighty-four patients were included in the study. Of the patients, 24.6% (140) were diagnosed with REM-dependent OSAS and 75.4% (444) were diagnosed as positional OSAS. Female predominance was found in REM-dependent OSAS (P < 0.001). The mean total apnea–hypopnea index (AHI), non-REM AHI, and supine AHI in REM-dependent OSAS were 14.73, 9.24, and 17.73, respectively, and these values were significantly lower when compared with positional OSAS (P < 0.001). Patients diagnosed with REM-dependent OSAS had a statistically significant tendency to be overweight (P < 0.001). For REM-dependent OSAS, total pulse rate, supine pulse rate, and REM pulse rate were statistically higher than positional OSAS (P < 0.001).CONCLUSION:Positional OSAS is a clinical entity that is more common than REM-dependent OSAS. OSAS severity is higher in positional OSAS than REM-dependent OSAS. REM-dependent OSAS is observed more commonly in women.

Obstructive sleep apnoea (OSA) is associated with airways inflammation; a key role in this regard seems to be played by nitric oxide (NO). The aim of this study was to measure exhaled NO and expression of its enzyme, the inducible nitric oxide synthase (iNOS) in cells of induced sputum in OSA patients and in obese subjects without sleep apnoea and to correlate these inflammatory markers with severity of OSA. We enrolled 18 obese patients with OSA (10 men, age 48.2 +/- 8.4 years), 15 obese patients without OSA (eight men, age 52.8 +/- 11 years) and 10 healthy subjects (five men, age 42 +/- 4 years). Exhaled NO was measured using a chemiluminescence analyser; iNOS expression was measured in the sputum cells by immunocytochemistry. Exhaled NO resulted significantly increased in OSA and in obese patients (23.1 +/- 2.1 and 17.9 +/- 2.1 p.p.b.) than in healthy subjects (7.2 +/- 0.6 p.p.b.; P < 0.001). OSA and obese patients showed a higher percentage of neutrophils and a lower percentage of macrophages in the induced sputum compared to healthy subjects. In addition, OSA and obese patients showed higher iNOS expression in neutrophils and in macrophages with respect to healthy subjects. A positive correlation between exhaled NO, iNOS expression and AHI was observed. These data confirm the presence of airway inflammation in OSA and in obese patients, and suggest the possible role for NO and iNOS expression in neutrophils of the induced sputum as noninvasive markers to identify and monitor the airway inflammation in these subjects.

The following is the abstract of the article discussed in the subsequent letter: Midlatency respiratory-related evoked potentials were measured during wakefulness by using a 60-electrode array placed over the cortical region of the scalp. We studied the responses evoked by 200-ms pressure pulses at

To evaluate the effects of a 2-year weight reduction program on respiratory disturbances, arousal index, daytime sleepiness, metabolic status, and quality of life in obese patients with obstructive sleep apnea syndrome (OSAS). Prospective intervention study of 33 consecutive obese OSAS patients (24 men, 9 women); 19 subjects used continuous positive airway pressure and 4 used mandibular retaining device, except during nights with sleep recording. The program consisted of 8 weeks of low calorie diet followed by group meetings with behavioral change support. Seventy percent of the patients completed the program; 67% completed the sleep recordings. The success rate for the apnea-hypopnea index (AHI) (< 20 and reduction > or = 50%) was 15% in the intention to treat (ITT) analysis. The AHI showed a nonsignificant decrease in mean values, from 43 to 28. The oxygen desaturation index (ODI) decreased from 42 to 23 (p = 0.010), arousal index from 24 to 11 (p = 0.019), body mass index from 40 to 35 (p = 0.003) and the Epworth Sleepiness Scale (ESS) from 9 to 5 (p = 0.026), all ITT. Metabolic status, physical functioning, and vitality evaluations improved only in the per protocol analysis. Reduction in weight correlated significantly to reductions in ESS (p = 0.038) and insulin levels (p = 0.002), respectively. There were no differences based on gender or use/non-use of OSAS treatment device. Our weight reduction program showed a limited success in reducing AHI. However, there were significant improvements in weight, ODI, arousal index, and subjective symptoms. We recommend the program as an adjunct treatment for well-motivated obese OSAS patients.

Objectives: Thisstudy aimed to examine factors (BMI, neck circumference, AHI etc.) affectingoptimal CPAP levels in patients with obstructive sleep apnea syndrome (OSAS).Materialsand Methods: A total of 120 patients with OSAS whounderwent successful auto-titration for CPAP treatment were included in thisstudy. Correlations between the optimal CPAP level and baseline data wereanalyzed.Results: Themean optimal pressure level in the 120 OSAS patients was 9.11 ± 2.81 cm H2O.The mean optimal pressure levels in the mild, moderate, and severe OSAS groups were8.01 ± 2.60, 8.32 ± 2.22, and 9.71 ± 3.01 cm H2O, respectively.Apnea/hypopnea index (AHI) (r=0.297, p&amp;amp;lt;0.001) and minimal SaO2(r=-0.264, p&amp;amp;lt;0.004) were significantly correlated with optimal pressurelevel. 22 patients in the titration failure group had severe AHI overall; 6patients had REM-related and 2 had position-related OSAS. Patients in the titrationfailure group who did not have a specific diagnosis (rapid eye movement (REM)or positional OSAS) had very severe AHI levels (mean AHI of 67.90). Conclusion: Accordingto the correlation tests, AHI and the lowest saturation were the two mostimportant predictors of optimal CPAP level.

Obstructive sleep apnea syndrome (OSAS) is associated with impairment of cognitive function, and improvement is often noted with treatment. Golf is a sport that requires a range of cognitive skills. We evaluated the impact of nasal positive airway pressure (PAP) therapy on the handicap index (HI) of golfers with OSAS. Golfers underwent a nocturnal polysomnogram (NPSG) to determine whether they had significant OSAS (respiratory disturbance index > 15). Twelve subjects with a positive NPSG were treated with PAP. HI, an Epworth Sleepiness Scale (ESS), and sleep questionnaire (SQ) were submitted upon study entry. After 20 rounds of golf on PAP treatment, the HI was recalculated, and the questionnaires were repeated. A matched control group composed of non-OSAS subjects was studied to assess the impact of the study construct on HI, ESS, and SQ. Statistical comparisons between pre- and post-PAP treatment were calculated. The control subjects demonstrated no significant change in HI, ESS, or SQ during this study, while the OSAS group demonstrated a significant drop in average HI (11.3%, p = 0.01), ESS, (p = 0.01), and SQ (p = 0.003). Among the more skilled golfers (defined as HI ≤ 12), the average HI dropped by an even greater degree (31.5%). Average utilization of PAP was 91.4% based on data card reporting. Treatment of OSAS with PAP enhanced performance in golfers with this condition. Treatment adherence was unusually high in this study. Non-medical performance improvement may be a strong motivator for selected subjects with OSAS to seek treatment and maximize adherence.

Objective: To investigate changes in cortical excitability in patients with obstructive sleep apnea syndrome (OSAS) undergoing 10Hz repetitive transcranial magnetic stimulation (rTMS) during wakefulness. Background OSAS is a syndrome characterized by repetitive upper airway collapse or narrowing during sleep with sequelae include adverse cardiovascular and metabolic outcomes, decline in quality of life, and neurocognitive impairment. Although altered cortical excitability in OSAS is well documented, the effect of rTMS on the excitability changes in OSAS patients has not previously been studied. This is important as rTMS can potentially be used as an adjunct therapy in OSAS. Design/Methods: We recruited 13 untreated severe OSAS (10 males, mean apnea-hypopnea index=54.6±13.01h) patients and 12 age-matched healthy volunteers. The TMS parameters measured were resting motor threshold (RMT), motor evoked potential (MEP) amplitude, central motor conduction time (CMCT), cortical silent period (CSP) and short-interval intracortical inhibition (SICI). These parameters were measured in the morning more than 2h after arising. After the baseline TMS studies, the patients and healthy volunteers were subjected to 10 Hz rTMS over left dorsolateral prefrontal cortex. The TMS parameters (RMT, MEP, CMCT, CSP and SICI) were repeated thereafter. Results: OSAS patients had a significantly higher RMT and a longer CSP duration (t-test, p 0.05). The rTMS showed an prolongation of CSP in OSAS subjects (ANOVA, p Conclusions: This TMS-based study suggests that untreated severe OSAS patients have imbalanced cortical excitabilities that enhanced inhibition or decreased brain excitability when awake during the day. The paradoxical response of rTMS in OSAS patients highlights the complex interplay of excitatory and inhibitory cortical circuits in OSAS. This intriguing result needs further replication. Disclosure: Dr. Das has nothing to disclose. Dr. Vijayakumari has nothing to disclose. Dr. Radhakrishnan has nothing to disclose.

Drug-induced sleep endoscopy in adults with sleep-disordered breathing: Technique and the VOTE Classification system

Objectives: The present case-control study aimed to determine whether obstructive sleep apnea syndrome (OSAS) patients are at an increased risk for sleepiness-related motor vehicle accidents (MVAs) than controls and to identify disease-related factors associated with accident risk. Methods: Demographic, anthropometric, clinical, and polysomnographic parameters of 312 OSAS patients were compared with 156 age- and sex-matched primary snoring subjects. Results: The rate of OSAS patients reporting accident was higher than snoring subjects (21.2% vs. 11.5%, P = .011), and OSAS was associated with an increase in accident risk (odds ratio = 2.06, 95% confidence interval [CI], 1.17 to 3.61, P = .012). Younger OSAS patients (P = .001) and those who were male (P = .001), had greater neck circumference (P = .002), had a higher Epworth sleepiness score (ESS; P < .0001), and had a higher apnea–hypopnea index (AHI; p = .039) had more MVAs than OSAS patients. Daytime sleepiness was associated with a 2.74-fold increase (95% CI, 1.54 to 4.87, P = .001) in accident risk. In multiple logistic regression analysis, accident risk was associated with neck circumference (P < .031) and ESS (P < .0001). In addition, accident risk could be excluded in OSAS patients with neck circumference < 43 cm and ESS < 11 (sensitivity 33.3%, specificity 85.8%). Conclusions: The present results show that OSAS patients have a twofold higher risk of traffic accidents than control subjects, and increased neck circumference and excessive daytime sleepiness are useful in predicting OSAS patients at higher risk of having accidents.

Objective To investigate the changes of vasoactive substance in obstructive sleep apnea syndrome (OSAS) patients with type 2 diabetes and type 2 diabetes mellitus (T2DM) and OSAS patients.Methods 50 cases of OSAS confirmed by polysomnography (PSG) were selected, which included 24 patients with type 2 diabetes and 26 without type 2 diabetes. 18 patients with type 2 diabetes were selected and 24 normal controls selected as the control group. Serum levels of nitric oxide (NO),endothelin 1 (ET-1), thromboxane A2 (TXA2), and high-sensitive C-creative protein (hs-CRP) in patients were detected by enzyme-linked immunosorbent assay (ELISA). Then we analysed the relativity between the changed above index and apnea-hypopnea index (AHI). Results ①AHI significantly elevated hs-CRP in patients with OSAS and the lowest oxygen saturation declined and the OSAS with T2DM more evident. ②Compared vasoactive substances between OSAS group and T2DM group with control group,serum levels of ET-1, hs-CRP, TXA2 were higher in patients with OSAS patients and T2DM patients than those in control group, and the level of NO and NO/ET-1 decreased in OSAS patients and T2DM patients. Then we found the changes more significant in OSAS with T2DM patients except for hs-CRP. ③In OSAS patients, the level of ET-1,TXA2 and hs-CRP has positive correlation with AHI and the level of NO and NO/ET-1 has negative correlation with AHI. Conclusions The results indicate that the patients with OSAS have obvious endothelial dysfunction, and the changes in OSAS with T2DM patients more severe. Key words: Obstructive sleep apnea syndrome; Type 2 diabetes mellitus; Vasoactive substance

Vitamin D status of male OSAS patients improved after long-term CPAP treatment mainly in obese subjects

Elevated risk of motor vehicle accidents in patients with obstructive sleep apnea syndrome: A case-control study

Analysis of obstruction site in obstructive sleep apnea syndrome patients by drug induced sleep endoscopy

Position therapy plays a role in treating snoring and obstructive sleep apnea syndrome (OSAS). The purpose of this study was to investigate whether position therapy using a head-positioning pillow (HPP) could reduce snoring sounds in patients with mild-to-moderate positional OSAS, taking into account the potential confounding effects of body weight. A total of 25 adults with positional OSAS (apnea-hypopnea index [AHI]supine:AHInon-supine ≥ 2) were prospectively enrolled. Patients were asked to use their own pillows at home during the first night (N0), and the HPP during the second (N1) and third (N2) nights. The primary outcome measures included the subjective snoring severity (SS, measured on a visual analogue scale ranging from 0 to 10) and the objective snoring index (SI, expressed as the number of snoring events per hour measured on an acoustic analytical program). Both endpoints were recorded over three consecutive nights. From N0 to N2, the median SS and SI values in the entire study cohort decreased significantly from 5.0 to 4.0 and from 218.0 events/h to 115.0 events/h, respectively. In the subgroup of overweight patients, SS showed a significant improvement, whereas SI did not. Both SS and SI were found to be significantly improved in normal-weight patients.