BACKGROUND AND PURPOSE: Obstructive sleep apnea (OSA) is more severe during rapid eye movement (REM) sleep than during non-REM sleep. We aimed to determine the features of patients with OSA who experience little REM sleep. METHODS: Patients with a chief complaint of sleep-disordered breathing were enrolled. All subjects underwent overnight polysomnography (PSG) and completed questionnaires on sleep quality. Patients were divided into the following three groups according to the proportion of REM sleep detected in overnight PSG: little REM sleep [REM sleep <20% of total sleep time (TST)], normal REM sleep (20–25% of TST), and excessive REM sleep (>25% of TST). Multiple logistic regression analyses were applied to the data. The success rate of continuous positive airway pressure (CPAP) titration was estimated in these groups. RESULTS: The age and body mass index of the patients were 47.9±15.9 years (mean±SD) and 25.2±4.1 kg/m², respectively. The 902 patients comprised 684 (76%) men and 218 (24%) women. The apnea-hypopnea index (AHI) in the little-REM-sleep group was 22.1±24.4 events/hour, which was significantly higher than those in the other two groups (p<0.05). Multiple logistic regression showed that a higher AHI (p<0.001; odds ratio, 1.512; 95% confidence interval, 1.020–1.812) was independently predictive of little REM sleep. The titration success rate was lower in the little-REM-sleep group than in the normal-REM-sleep group (p=0.038). CONCLUSIONS: The AHI is higher and the success rate of CPAP titration is lower in OSA patients with little REM sleep than those with normal REM sleep.
Body Mass Index ; Continuous Positive Airway Pressure ; Female ; Humans ; Logistic Models ; Male ; Odds Ratio ; Polysomnography ; Sleep Apnea Syndromes ; Sleep Apnea, Obstructive* ; Sleep, REM*

No abstract available.
Amnesia, Transient Global* ; Humans ; Writing*

Objectives: Functional dyspepsia is one of the most common functional gastrointestinal disorders. We aimed to investigate the relationship between obstructive sleep apnea (OSA) and functional dyspepsia in patients with the complaint of sleep-disordered breathing. Methods: We prospectively recruited patients who visited the institute for the evaluation of sleep-disordered breathing. All patients underwent overnight polysomnography and submitted their responses to sleep questionnaires. A validated Korean version of the Rome III criteria was used to estimate functional dyspepsia. Functional dyspepsia was classified into two subtypes of epigastric pain syndrome and postprandial distress syndrome. Results: Out of 130 subjects with sleep disturbances, a total of 79 patients (60 men, 19 women) were enrolled. The mean (±standard deviation) age was 46.9±13.4 years. Functional dyspepsia was diagnosed in 8 (10%) patients. Patients with functional dyspepsia showed significantly higher values of Stanford Sleepiness Scale, the proportion of N1 sleep, arousal index, and apnea-hypopnea index compared to patients without functional dyspepsia (p=0.018, p=0.021, p=0.041, and p=0.039, respectively). With respect to OSA severity, 12% of patients with moderate OSA and 22% patients with severe OSA had functional dyspepsia. Severe OSA was significantly associated with a higher proportion of postprandial distress syndrome (p=0.030). Conclusions Our patients with snoring or OSA revealed that functional dyspepsia is associated with more severe daytime sleepiness and apnea-hypopnea index compared to those without functional dyspepsia. In addition, postprandial distress syndrome was a prevalent subtype of functional dyspepsia in patients with severe OSA.

BACKGROUND AND PURPOSE: Discrepancies between objectively measured sleep and subjective sleep perception in patients with insomnia have been reported. However, few studies have investigated sleep-state misperception in patients with obstructive sleep apnea (OSA). We designed this study to 1) delineate the factors that could affect this discrepancy and 2) infer an underlying mechanism in patients with OSA. METHODS: We recruited patients who visited our sleep clinic for the evaluation of their snoring and/or observed OSA. Participants completed a structured questionnaire and underwent overnight polysomnography. On the following day, five sessions of the multiple sleep latency test (MSLT) were applied. We divided the patients into two groups: normal sleep perception and abnormal perception. The abnormal-perception group included patients whose perceived total sleep time was less than 80% of that measured in polysomnography. RESULTS: Fifty OSA patients were enrolled from a university hospital sleep clinic. Excessive daytime sleepiness, periodic limb movement index (PLMI), and the presence of dreaming were positively associated with poor sleep perception. REM sleep near the sleep termination exerted important effects. Respiratory disturbance parameters were not related to sleep perception. There was a prolongation in the sleep latency in the first session of the MSLT and we suspected that a delayed sleep phase occurred in poor-sleep perceivers. CONCLUSIONS: As an objectively good sleep does not match the subjective good-sleep perception in OSA, physicians should keep in mind that OSA patients who perceive that they have slept well does not mean that their OSA is less severe.
Dreams ; Extremities ; Humans ; Polysomnography* ; Sleep Apnea, Obstructive* ; Sleep Initiation and Maintenance Disorders ; Sleep, REM ; Snoring

Purpose: To investigate the effects of simultaneous soft and hard tissue augmentation and the addition of polydeoxyribonucleotide (PDRN) on regenerative outcomes. Materials and Methods: In five mongrel dogs, chronic ridge defects were established in both mandibles. Six implants were placed in the mandible, producing buccal dehiscence defects. The implants were randomly allocated to one of the following groups: 1) control: no treatment; 2) GBR: guided bone regeneration (GBR) only; 3) GBR/PDRN: GBR+PDRN application to bone substitute particles; 4) GBR/CTG: GBR+connective tissue grafting (CTG);5) GBR/VCMX: GBR+soft tissue augmentation using volume stable collagen matrix (VCMX); and 6) group GBR/VCMX/ PDRN: GBR+VCMX soaked with PDRN. The healing abutments were connected to the implants to provide additional room for tissue regeneration. Submerged healing was achieved. The animals were euthanized after four months. Histological and histomorphometric analyses were then performed. Results: Healing abutments were gradually exposed during the healing period. Histologically, minimal new bone formation was observed in the dehiscence defects. No specific differences were found between the groups regarding collagen fiber orientation and density in the augmented area. No traces of CTG or VCMX were detected. Histomorphometrically, the mean tissue thickness was greater in the control group than in the other groups above the implant shoulder (IS). Below the IS level, the CTG and PDRN groups exhibited more favorable tissue thickness than the other groups. Conclusion Failure of submerged healing after tissue augmentation deteriorated the tissue contour. PDRN appears to have a positive effect on soft tissues.

BACKGROUND AND PURPOSE: Restless legs syndrome (RLS) is a sleep disorder that frequently occurs in dialysis patients, which disturbs the sleep and reduces the quality of life. The aim of this study was to determine the risk factors for RLS in dialysis patients. METHODS: Patients who visited any of four outpatient dialysis clinics between September 2005 and May 2006 were included in this study. The diagnosis of RLS and the severity assessment were made using the criteria described by the International Restless Legs Syndrome Study Group. We collected basic demographic data, clinical information, and laboratory findings, and then analyzed their association with various aspects of RLS using univariate and multivariate analyses. RESULTS: RLS was present in 46 (28.0%) of 164 dialysis patients. We found no significant risk factor for inducing RLS. The predialysis serum blood urea nitrogen (BUN) level in the dialysis patients with RLS was significantly correlated with RLS symptom severity. CONCLUSIONS: Predialysis BUN is related to RLS symptom severity. Further studies on the underlying mechanism are needed.
Blood Urea Nitrogen ; Dialysis ; Humans ; Multivariate Analysis ; Outpatients ; Quality of Life ; Renal Dialysis ; Restless Legs Syndrome ; Risk Factors

No abstract available.
Continuous Positive Airway Pressure ; Humans

Background: Recent genomic studies identified four discrete molecular subgroups of medulloblastoma (MB), and the risk stratification of childhood MB in the context of subgroups was refined in 2015. In this study, we investigated the effect of molecular subgroups on the risk stratification of childhood MB. Methods: The nCounter® system and a customized cancer panel were used for molecular subgrouping and risk stratification in archived tissues. Results: A total of 44 patients were included in this study. In clinical risk stratification, based on the presence of residual tumor/metastasis and histological findings, 24 and 20 patients were classified into the average-risk and high-risk groups, respectively. Molecular subgroups were successfully defined in 37 patients using limited gene expression analysis, and DNA panel sequencing additionally classified the molecular subgroups in three patients. Collectively, 40 patients were classified into molecular subgroups as follows: WNT (n = 7), SHH (n = 4), Group 3 (n = 8), and Group 4 (n = 21). Excluding the four patients whose molecular subgroups could not be determined, among the 17 average-risk group patients in clinical risk stratification, one patient in the SHH group with the TP53 variant was reclassified as very-high-risk using the new risk classification system. In addition, 5 of 23 patients who were initially classified as high-risk group in clinical risk stratification were reclassified into the low- or standard-risk groups in the new risk classification system. Conclusion The new risk stratification incorporating integrated diagnosis showed some discrepancies with clinical risk stratification. Risk stratification based on precise molecular subgrouping is needed for the tailored treatment of MB patients.

Purpose: Detection of telomerase reverse transcriptase (TERT) promoter mutations is a crucial process in the integrated diagnosis of glioblastomas. However, the TERT promoter region is difficult to amplify because of its high guanine-cytosine (GC) content (> 80%). This study aimed to analyze the capturing of TERT mutations by targeted next-generation sequencing (NGS) using formalin-fixed paraffin-embedded tissues. Materials and Methods: We compared the detection rate of TERT mutations between targeted NGS and Sanger sequencing in 25 cases of isocitrate dehydrgenase (IDH)-wildtype glioblastomas and 10 cases of non-neoplastic gastric tissues. Our customized panel consisted of 232 essential glioma-associated genes. Results: Sanger sequencing detected TERT mutations in 17 out of 25 glioblastomas, but all TERT mutations were missed by targeted NGS. After the manual visualization of the NGS data using an integrative genomics viewer, 16 cases showed a TERT mutation with a very low read depth (mean, 21.59; median, 25), which revealed false-negative results using auto-filtering. We optimized our customized panel by extending the length of oligonucleotide baits and increasing the number of baits spanning the coverage of the TERT promoter, which did not amplify well due to the high GC content. Conclusion Our study confirmed that it is crucial to consider the recognition of molecular bias and to carefully interpret NGS data.

BACKGROUND: We previously reported that percutaneous dilatational tracheostomy (PDT) can be safely performed 2 cm below the cricothyroid membrane without the aid of a bronchoscope. Although our simplified method is convenient and does not require sophisticated equipment, the precise location for tracheostomy cannot be confirmed. Because it is recommended that tracheostomy be performed at the second tracheal ring, we assessed whether patient characteristics could predict the distance between the cricothyroid membrane and the second tracheal ring. METHODS: Data from 490 patients who underwent three-dimensional neck computed tomography from January 2012 to December 2015 were analyzed, and the linear distance from the upper part of the cricoid cartilage (CC) to the lower part of the second tracheal ring (2TR) was measured in the sagittal plane. RESULTS: The mean CC-to-2TR distance was 25.26 mm (95% CI 25.02–25.48 mm). Linear regression analysis showed that the predicted CC-to-2TR distance could be calculated as −5.73 + 0.2 × height (cm) + 1.22 × sex (male: 1, female: 0) + 0.01 × age (yr) −0.03 × weight (kg) (adj. R² = 0.55). CONCLUSIONS These results suggest that height and sex should be considered when performing PDT without bronchoscope guidance.