Association of obstructive sleep apnea and diurnal variation of cystatin C.

PURPOSE: Obstructive sleep apnea is a known risk factor for the progression of chronic kidney disease. To find early signs of the progression in subjects with obstructive sleep apnea., we assessed the diurnal variation of kidney biomarkers. METHODS: A prospective observational study was conducted at Kangwon National University Hospital, Chuncheon, South Korea. All participants underwent in-laboratory polysomnography and phlebotomy in the evening before the polysomnography and in the morning after the polysomnography. Kidney biomarkers, including serum creatinine, blood urea nitrogen, and serum cystatin C, were measured. Delta kidney biomarkers were calculated by subtracting the evening level of the biomarkers from the morning level. RESULTS: Twenty-six of 50 participants had severe obstructive sleep apnea. Delta cystatin C was significantly correlated with apnea-hypopnea index, oxygen desaturation index, and total arousal index with coefficients of -0.314, -0.323, and -0.289, respectively. In participants without severe obstructive sleep apnea, the morning cystatin C level (0.84 ± 0.11 mg/L) was significantly higher than the evening cystatin C level (0.81 ± 0.11 mg/L) (P = 0.005). With severe obstructive sleep apnea, the cystatin C levels were not different between the morning (0.85 ± 0.11 mg/L) and the evening (0.85 ± 0.10 mg/L). CONCLUSIONS: Cystatin C level was increased in the morning in participants without severe obstructive sleep apnea, but not in participants with severe obstructive sleep apnea.

The 24-Hour Cardiac Autonomic Activity in Patients With Allergic Rhinitis.

BACKGROUND: Definitive knowledge of the 24-hour cardiac autonomic activity in patients with allergic rhinitis (AR) is lacking. Thus, we aimed to evaluate heart rate variability (HRV), which is used to measure cardiac autonomic activity by 24-hour Holter monitoring in patients with AR. METHODS: We enrolled 32 patients who visited our clinic and were diagnosed with AR. The control group was selected four-fold (n = 128) by matching (age, sex, hypertension, and diabetes) in the AR group from a Holter registry in the cardiology department. The HRV results, which were measured using 24-hour Holter monitoring, were compared between the AR and control groups. RESULTS: All time-domain parameters of HRV revealed no differences between the groups. However, among the frequency domain parameters of HRV, the low-frequency to high-frequency ratio and low-frequency power in normalized units were significantly lower in the AR group. Conversely, high-frequency power in normalized units was significantly higher in the AR group. In the multiple regression analysis, AR was independently associated with sympathetic withdrawal (adjusted odds ratio = 3.393, P = 0.020) after adjusting for age, sex, hypertension, diabetes mellitus, and hyperlipidemia. CONCLUSIONS: The present findings suggest differences in cardiac autonomic activity which are related with sympathetic withdrawal in patients with AR compared with that in the normal population over 24 hours.

Prevalence and Contributing Factors of Anxiety and Depression in Patients with Vestibular Migraine.

Objective: Anxiety and depression are psychiatric comorbidities potentially associated with dizziness and migraine, which can influence disease state, prognosis, and clinical outcomes. Vestibular migraine (VM) is a disease that causes repeated vestibular symptoms in people with a history of migraines. We investigated the prevalence and contributing factors of anxiety and depression in patients with VM. Methods: A total of 74 patients with VM were enrolled in this study. All patients underwent pure-tone audiometry, the examination of spontaneous nystagmus, Dix-Hallpike maneuver or supine-roll test, video head impulse test, and caloric testing on the day of the visit. We used the Hospital Anxiety and Depression Scale (HADS) to assess the symptoms of anxiety and depression. Dizziness Handicap Inventory was used to measure the intensity of vestibular symptoms. The participants were divided into normal and abnormal groups based on their HADS anxiety and depression scores, and demographic and clinical factors were analyzed. To identify factors associated with anxiety and depression, multivariate logistic regression analyses were performed. Results: A total of 36 (48.6%) patients demonstrated clinically relevant anxiety levels, and 24 (32.4%) demonstrated depression. Twenty-five (33.8%) patients were diagnosed with peripheral vestibular dysfunction. In the multivariable analyses, peripheral vestibular dysfunction and severe intensity vestibular symptoms were significantly associated with anxiety and depression. None of migraine features were significantly associated with anxiety and depression. Conclusion: The prevalence of anxiety in patients with VM is considerably higher than in the depression. VM patients with peripheral vestibular dysfunction are particularly susceptible to anxiety and depression. Therefore, timely screening for vestibular function and psychiatric disorders in VM patients should be considered.

Impact of the COVID-19 and Socioeconomic Status on Access to Care for Otorhinolaryngology Patients.

Since December 2019, COVID-19 has greatly influenced public healthcare systems around the globe in various aspects, including limitation of healthcare accessibility due to lack of both human and financial resources, suspension of clinics, and fear of infection causing healthcare avoidance. The aim of this study was to investigate the impact of COVID-19 on access to healthcare for otorhinolaryngology patients from different socioeconomic status (SES) groups. Otorhinolaryngology patients' disease severity status, diagnosed at the first hospital visit, was investigated during the pre -and post-COVID-19 pandemic era in a single medical center located in Seoul, Korea. An ordinal regression model was used to assess the impact of both SES and the COVID-19 pandemic on otorhinolaryngology diseases. Within the chronic rhinosinusitis group, lower SES was associated with a higher disease severity at the first visit compared to higher SES (OR = 3.25). During the COVID-19 pandemic, while the total number of outpatients was reduced, the severity of these ENT diseases seemed to increase compared to the pre-pandemic severity in every SES group. Our study demonstrates the negative impact a worldwide pandemic can have on healthcare inequity and disease severity, and highlights the importance of re-allocating fundamental resources for those in need during periods of public health crisis.

The differences between daytime and nighttime heart rate variability may usefully predict the apnea-hypopnea index in patients with obstructive sleep apnea.

STUDY OBJECTIVES: The association between daytime/nighttime heart rate variability (HRV) and the apnea-hypopnea index (AHI) remains unclear. We sought a relationship between AHI and the daytime-to-nighttime HRV ratio as measured by 24-hour Holter monitoring in patients with obstructive sleep apnea. METHODS: We prospectively enrolled 66 patients who visited our sleep clinic complaining of habitual snoring or sleep apnea. All underwent 24-hour Holter monitoring (to measure HRV) combined with full-night polysomnography. Sixty-two met our enrollment criteria. We evaluated the associations between HRV frequency domains and the polysomnography indices. We also considered medical histories and anthropometric data. RESULTS: The nighttime very-low-frequency (VLF), low-frequency (LF), and high-frequency HRVs were significantly higher than the daytime values. On correlation analysis, the day/night VLF (r = .550, P < .001), LF (r = .556, P < .001), and high-frequency (r = .303, P = .017) HRVs were significantly related to the AHI. Of the day/night HRV ratios, the VLF (P for trend = .003) and LF (P for trend = .013) ratios decreased significantly by obstructive sleep apnea severity. Multivariable analysis showed that the day/night VLF (ß = 16.387, P < .001) and day/night LF (ß = 25.248, P < .001) were independently (and significantly) associated with the AHI. CONCLUSIONS: Twenty-four-hour Holter monitoring may usefully predict AHI. The day/night VLF and day/night LF ratios tended to decrease by obstructive sleep apnea severity and were independently associated with the AHI. CITATION: Nam E-C, Chun KJ, Won JY, Kim J-W, Lee WH. The differences between daytime and nighttime heart rate variability may usefully predict the apnea-hypopnea index in patients with obstructive sleep apnea. J Clin Sleep Med. 2022;18(6):1557-1563.

Effect of sinus opacification on the severity of obstructive sleep apnea.

PURPOSE: The association between rhinosinusitis and obstructive sleep apnea (OSA) remains unclear. Here, we aimed to elucidate the association between sinus opacification and OSA severity. METHODS: Patients with snoring problems who visited our clinic from April 2018 to December 2020 were retrospectively enrolled. Among these patients, we included those who underwent a physical examination, overnight polysomnography, and osteomeatal-unit computed tomography. We evaluated the association between apnea-hypopnea index (AHI) and Lund-Mackay score (LMS). LMS ≥ 5 was considered indicative of sinus opacification. RESULTS: Among the 122 patients included in the study, LMS exhibited an increasing trend based on OSA severity. The LMS in the moderate OSA group was significantly higher than that in the no OSA group (P = 0.002), and the LMS in the severe OSA group was significantly higher than that in the no OSA (P < 0.001) and mild OSA (P = 0.006) groups. A correlation analysis revealed that AHI was significantly associated with body mass index (BMI) (r = 0.367, P < 0.001) and LMS (r = 0.255, P = 0.005). A multivariate analysis revealed that sinus opacification was associated with moderate and severe OSA [Adjusted odds ratio = 11.986 (P = 0.005) and 3.756 (P = 0.044), respectively] after adjusting for age, sex, BMI, smoking, hypertension, atopy, tonsil size, and palatal position. The effect of sinus opacification on OSA severity was comparable to that of overweight. CONCLUSION: Sinus opacification may increase OSA severity since moderate and severe OSA is independently associated with it.

Age Differences in Pet Sensitization by Pet Ownership.

OBJECTIVES: The association between pet sensitization and pet ownership remains unclear. Therefore, we aimed to elucidate the association between pet sensitization and pet ownership by age. METHODS: We retrospectively reviewed 2,883 patients who visited our allergy clinic for nasal symptoms from January 2003 to December 2014, of whom 1,957 patients with data on skin-prick tests and questionnaire responses were included and divided into adults (age >19 years) and children (age ≤19 years). The association between pet sensitization and pet ownership was evaluated in both groups. RESULTS: Among children, dog and cat sensitization showed no associations with dog and cat ownership, respectively. However, among adults, dog sensitization was significantly associated with dog ownership (odds ratio [OR], 3.283; P<0.001), and cat sensitization with cat ownership (OR, 13.732; P<0.001). After adjustment for age, sex, familial history of allergy, sinusitis, diabetes mellitus, other pet ownership, and non-pet sensitization, significant associations remained between dog sensitization and dog ownership (adjusted OR [aOR], 3.881; P<0.001), and between cat sensitization and cat ownership (aOR, 10.804; P<0.001) among adults. Dog ownership did not show any association with allergic rhinitis, asthma, or atopic dermatitis, whereas atopic dermatitis had a significant association with cat ownership in adults (aOR, 4.840; P<0.001). CONCLUSION: Pet ownership in adulthood increased the risk of pet sensitization. However, pet ownership was not associated with the prevalence of atopic disorders, regardless of age, except for atopic dermatitis and cat ownership in adults.

Clinical Manifestations of Allergic Rhinitis by Age and Gender: A 12-Year Single-Center Study.

OBJECTIVES: Currently, epidemiological data on allergic rhinitis collected through the skin prick test are scarce. Moreover, the relationship of age and sex to allergic rhinitis is not comprehensively understood. This study aimed to characterize allergic rhinitis and the associated clinical manifestations by age and sex. METHODS: We retrospectively investigated data from 2883 patients who visited a single university hospital for rhinitis symptoms between January 2003 and December 2014. Of these 2883 patients, 1964 who underwent a skin prick test with 11 standardized allergen extracts and completed a nasal symptom questionnaire were enrolled. The clinical characteristics of allergen sensitization and nasal symptoms were analyzed by sex and age distribution. RESULTS: The prevalence of allergen sensitization progressively decreased with age after peaking at between 20 and 29 years. The sensitization rate was higher in males than in females (P = .046). The sensitization rate to house dust mites decreased with age, while sensitization to mugwort and ragweed increased. Six allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae, mugwort, trees, ragweed, and cats) were sufficient to identify >96% of patients with allergen sensitization. Nasal obstruction tended to decrease with age and was more prevalent in males (P = .002) than in females, while rhinorrhea (P = .007) and itching (P = .013) were more prevalent in females. Total nasal symptom scores did not differ by sex. CONCLUSIONS: The clinical characteristics of allergic rhinitis, including allergen-sensitization patterns and related symptoms, varied by age and sex. Six common allergens could be sufficient to generate a cost-effective tool to identify allergic rhinitis.

Heterogeneity of Adult Rhinitis for Multimorbidity and Age at Onset among Non-Sensitized Rhinitis and Mono-/Poly-Sensitized Rhinitis: A Retrospective Cross-Sectional Study.

BACKGROUND: Recent studies have proposed that clinical and immunological differences exist between mono- and poly-sensitized subjects with allergic diseases, and poly-sensitization was related to multimorbidity of allergic diseases among children and adolescents. OBJECTIVE: We compared the clinical characteristics and multimorbidity of allergic diseases between adult rhinitis patients mono- and poly-sensitized to common aeroallergens using a retrospective cross-sectional study for tertiary care subjects. METHODS: The medical records of 1,615 patients who were clinically diagnosed with rhinitis by an otolaryngologist and evaluated with skin prick tests were reviewed. The severity of the rhinitis symptoms, comorbidities (asthma, conjunctivitis, and eczema), family history of allergic diseases, and the results of skin prick tests were evaluated. RESULTS: There were 392 patients with mono-sensitized rhinitis (mono-sR), 325 with poly-sensitized rhinitis (poly-sR), and 898 with non-sensitized rhinitis (non-sR). Comorbid conjunctivitis and eczema were most common in poly-sR, followed by mono-sR, and least common in non-sR patients. The age at onset of rhinitis was clearly different between adult patients with non-sR and mono-/poly-sR, but not between patients with mono-sR and poly-sR. However, the age at onset of rhinitis was much younger in non-sR and mono-sR patients with conjunctivitis or eczema than those without such comorbidities. CONCLUSION: Thefrequency of comorbid conjunctivitis and eczema in adult rhinitis patients differed by a quantitative trait of immunoglobulin E sensitization. Depending on the multimorbidity of allergic diseases, onset age of rhinitis seems to be different in adult rhinitis patients.

Effectiveness of sleep surgery versus a mandibular advancement device for obstructive sleep apnea in terms of nocturnal cardiac autonomic activity.

PURPOSE: Sleep surgery and mandibular advancement devices (MAD) are treatments for obstructive sleep apnea (OSA), but their comparative efficacy remains unclear. We compared their efficacy using various parameters. METHODS: Subjects treated for OSA with sleep surgery or MAD (n = 30/group)-matched for sex, body mass index (BMI), and baseline apnea-hypopnea index (AHI)-were enrolled. The efficacy of these treatments according to polysomnographic parameters, sleep quality questionnaires, and heart rate variability (HRV) time- and frequency-domain parameters were compared between pre-treatment and 3-month post-treatment. RESULTS: Polysomnographic and sleep quality questionnaire parameters improved significantly in both groups. In time-domain HRV analysis, average normal-to-normal intervals increased significantly in the surgery (942.2 ± 140.8 to 994.6 ± 143.1, P = 0.008) and MAD (901.1 ± 131.7 to 953.7 ± 123.1, P = 0.002) groups. Low frequency (LF) decreased significantly in the surgery group (P = 0.012); high frequency (HF) remained unchanged in both groups. The LF/HF ratio decreased in both groups (2.9 ± 1.8 to 2.3 ± 1.7, P = 0.017, vs. 3.0 ± 1.8 to 2.4 ± 1.4, P = 0.025). Normalized high frequency increased significantly in both groups (31.0 ± 13.2 to 36.8 ± 13.7, P = 0.009, vs. 29.1 ± 10.7 to 33.7 ± 12.5, P = 0.024), in contrast to normalized low frequency. However, no HRV parameter changes differed significantly between the groups after adjusting for age, BMI, and AHI. CONCLUSION: Sleep surgery and MAD are equally effective treatments for OSA according to cardiac autonomic activity.

Nocturnal heart rate variability may be useful for determining the efficacy of mandibular advancement devices for obstructive sleep apnea.

A mandibular advancement device (MAD) is recommended as an alternative therapy for obstructive sleep apnea (OSA), which effectively reduces the collapsibility of the upper airway during sleep by advancing the mandible. However, the effects of MAD therapy on cardiac autonomic modulation remain unclear. We evaluated the effects of MAD on nocturnal heart rate variability (HRV) in OSA. Anthropometric data, questionnaire results, and HRV parameters (evaluated using time domain and frequency domain methods) of 58 adult patients with OSA treated with MAD therapy were retrospectively reviewed. All patients underwent polysomnography at baseline and 3-month follow-up. The average normal-to-normal (NN) interval, standard deviation of the NN interval, low-frequency power in normalized units (LFnu), and high-frequency power in normalized units (HFnu) showed significant changes with MAD therapy. Based on the criteria for success (decrease in the apnea-hypopnea index by >50% and value <20/h), 34 and 24 patients were classified into the response and nonresponse groups, respectively. No differences in baseline characteristics were detected between groups, except for higher body mass index and lower minimal oxygen saturation in the nonresponse group. A subgroup analysis indicated that the average NN interval and HFnu significantly increased, and that Total power (TP), very low frequency, low frequency(LF), low frequency/high frequency and LFnu significantly decreased compared to baseline in the response group; however, no HRV changes were found in the nonresponse group. After adjusting for age, sex, and body mass index, the response group showed significant changes from baseline in TP and LF compared to the nonresponse group. Therefore, HRV may be useful for determining the efficacy of MAD therapy in OSA.

The NADP+-dependent glutamate dehydrogenase Gdh1 is subjected to glucose starvation-induced reversible aggregation that affects stress resistance in yeast.

The yeast Saccharomyces cerevisiae has two isoforms of NADP+-dependent glutamate dehydrogenase (Gdh1 and Gdh3) that catalyze the synthesis of glutamate from α-ketoglutarate and NH4+. In the present study, we confirmed that Gdh3, but not Gdh1, mainly contributes to the oxidative stress resistance of stationary-phase cells and found evidence suggesting that the insignificance of Gdh1 to stress resistance is possibly resulted from conditional and reversible aggregation of Gdh1 into punctuate foci initiated in parallel with post-diauxic growth. Altered localization to the mitochondria or peroxisomes prevented Gdh1, which was originally localized in the cytoplasm, from stationary phase-specific aggregation, suggesting that some cytosolic factors are involved in the process of Gdh1 aggregation. Glucose starvation triggered the transition of the soluble form of Gdh1 into the insoluble aggregate form, which could be redissolved by replenishing glucose, without any requirement for protein synthesis. Mutational analysis showed that the N-terminal proximal region of Gdh1 (NTP1, aa 21-26, TLFEQH) is essential for glucose starvation-induced aggregation. We also found that the substitution of NTP1 with the corresponding region of Gdh3 (NTP3) significantly increased the contribution of the mutant Gdh1 to the stress resistance of stationary-phase cells. Thus, this suggests that NTP1 is responsible for the negligible role of Gdh1 in maintaining the oxidative stress resistance of stationary-phase cells and the stationary phase-specific stresssensitive phenotype of the mutants lacking Gdh3.

Tinnitus Suppression Effect of Hearing Aids in Patients With High-frequency Hearing Loss: A Randomized Double-blind Controlled Trial.

INTRODUCTION: Hearing aids (HAs) with frequency lowering have been used for high-frequency hearing loss (HFHL), but their effects on tinnitus relief have not been studied extensively. This randomized double-blind trial was performed to investigate and compare tinnitus suppression effects of conventional type HAs and frequency-lowering HAs in patients with HFHL. METHODS: A total of 114 patients were randomized into three groups: conventional HA using wide dynamic range compression, HA with frequency translation, and HA with linear frequency transposition. Participants wore HAs for 3 months and then discontinued their use. The final evaluation was performed at 3 months after cessation of wearing HA (6 mo after the initial visit). The Tinnitus Handicap Inventory (THI) score and additional variables, such as matched tinnitus loudness and visual analog scale scores of subjectively perceived tinnitus loudness, daily awareness, and annoyance, were measured at the initial visit and at 3- and 6-month follow-ups. RESULTS: THI score and most of the additional outcomes were significantly improved at 3 and 6 months (3 mo after HA removal) compared with their initial values in all three groups. The incidence rates of patients with improvements in the THI score by 20% or more were 71.0, 72.7, and 74.3% at 3 months, and 54.8, 51.6, and 59.4% at 6 months for the three groups, respectively. There were no significant differences in primary or additional variables between hearing aid types at either 3 or 6 months. CONCLUSION: This is a consolidated standards of reporting trials-guided study providing direct evidence for tinnitus suppression effects of HA alone, without accompanying counseling or any other treatments, which lasted for at least 3 months after patients stopped using HAs. HAs effectively suppressed tinnitus in patients with HFHL regardless of the amplification strategy type.

Sequential versus Combination Treatment Using Steroids and Diuretics for Acute Low-Frequency Sensorineural Hearing Loss: A Noninferiority Trial.

OBJECTIVE: Acute low-frequency hearing loss (ALHL) is typically treated with combination therapy, including steroids and diuretics. To avoid unnecessary use of steroids we proposed a method of sequential administration using these two drugs, and compared the efficacy of our protocol with that of existing combination treatments. METHODS: A prospective, randomized, open-label, single-blind, noninferiority clinical trial was conducted to investigate whether the effectiveness of sequential treatment is noninferior to that of combination treatment for ALHL. Ninety-two patients with ALHL received either steroids and diuretics simultaneously for 2 weeks (combination group), or diuretics for 2 weeks followed by steroids for another 2 weeks if they did not respond to diuretic treatment (sequential group). The primary outcome measure was a change in mean hearing threshold at three frequencies (125, 250, and 500 Hz) at 4 weeks after treatment. RESULTS: The mean hearing threshold of the low frequencies improved 20.0 and 17.2 dB in the combination and the sequential group, respectively. The 95% lower confidence interval was -8.0 dB and noninferiority was established at p < 0.05. At 4 weeks after treatment, the complete recovery rate was 80.5 and 82.9% in the combination and sequential groups, respectively. CONCLUSION: This is the first study on ALHL treatment following the establishment of Consolidated Standards of Reporting Trials (CONSORT). The sequential treatment is not inferior to combination treatment for ALHL, and therefore may be a better treatment guideline for ALHL considering that patients receive less steroid exposure and smaller restrictions in diuretic use compared with steroids.

Blood eosinophils may predict radiographic sinus opacification in patients with chronic rhinitis.

BACKGROUND: The association between chronic rhinosinusitis (CRS) and chronic rhinitis remains unclear. The aim of this study was to estimate the predictive factors for sinus opacification in chronic rhinitis patients without obvious CRS. METHODS: We retrospectively studied a total of 332 adult patients with chronic rhinitis who visited our clinic from January 2015 to December 2017. All of the patients underwent endoscopic examination, allergy test, and osteomeatal-unit computed tomography. The subjects were assigned to the normal sinus (NS) group (Lund-Mackay score [LMS] <5) and sinus opacification (SO) group (LMS ≥5). RESULTS: A total of 288 patients were eligible for this study. Of them, 183 (63.5%) were classified in the NS group and 105 (36.5%) in the SO group. Total immunoglobulin E (IgE) level and peripheral blood eosinophil count were significantly higher in the SO than NS group (p = 0.031 and p < 0.0001, respectively). Using Pearson correlation coefficients, we determined that eosinophil count had a positive correlation with the LMS (r = 0.282). In logistic analysis, the interquartile range increase (0.19 × 109 /L) of the eosinophil count was significantly associated with SO (odds ratio [OR] 1.76; 95% confidence interval [CI], 1.30 to 2.39). After adjusting for age, gender, smoking, drinking, and underlying disease, the interquartile range increase of the eosinophil count increased the odds of SO to 1.69-fold; this increase was statistically significant (p = 0.007; 95% CI, 1.17 to 2.43). CONCLUSION: Peripheral blood eosinophil count is an independent predictor of CRS in patients with chronic rhinitis.

Changes in the regional shape and volume of subcortical nuclei in patients with tinnitus comorbid with mild hearing loss.

PURPOSE: Tinnitus, the perception of sound without an external source, is a prevalent disease, but its underlying mechanism has not been fully elucidated. Recent studies have suggested the involvement of subcortical nuclei in tinnitus generation. We investigated changes in the local shape and volume of subcortical nuclei in relation to tinnitus. METHODS: The participants included 53 patients with tinnitus and 52 age- and gender-matched normal controls. Individual 3D T1-weighted structural images were obtained using 3-T magnetic resonance imaging. Surface-based vertex analysis (SVA) was performed with automated segmentation of the bilateral caudate nuclei, putamina, nucleus accumbens, thalami, pallidum, hippocampi, amygdalae, and brainstem. The scalar distances from the mean surface and volumes of 15 nuclei were compared between the tinnitus and control groups and correlated with tinnitus handicap score (THI) and tinnitus duration. RESULTS: SVA revealed regional contractions in the accessory basal and lateral nuclei of the right amygdala and expansions in the left medial and right ventral posterior nuclei and lateral dorsal nucleus of both thalami. The surface distances of the right nucleus accumbens were positively correlated with tinnitus duration, while those of the left nucleus accumbens and left hippocampus were negatively correlated with THI. CONCLUSION: Regional atrophy of the amygdala may indicate self-modulation of emotional response regulation to diminish tinnitus-related emotional distress. Thalamic regional expansion may signify dysfunctional auditory gating in the thalamus, where inhibition of the tinnitus signal at the thalamus level is disrupted due to abnormal changes in the limbic system, ultimately leading to the tinnitus percept.

Soft palate cephalometric changes with a mandibular advancement device may be associated with polysomnographic improvement in obstructive sleep apnea.

PURPOSE: It is unclear whether soft palate-associated changes in cephalometry associated with a mandibular advancement device (MAD) are independently associated with improvements in polysomnography (PSG) respiratory parameters in obstructive sleep apnea (OSA). METHODS: This retrospective review aimed to identify the association between soft palate-associated changes in cephalometry and PSG changes after application of an MAD. Korean patients diagnosed with OSA who underwent cephalometry with or without an MAD were enrolled. All the patients were evaluated after undergoing full-night PSG twice: once with an MAD and once without. Cephalometric findings were measured using an image analyzer. RESULTS: Mean apnea-hypopnea index significantly decreased with an MAD from 36.4/h to 14.7/h (p < 0.001). Retropalatal airway space significantly increased with an MAD from 6.6 to 7.3 mm (p = 0.013). Soft palate length also significantly decreased with an MAD from 43.6 to 42.3 mm (p = 0.02). Although these findings were shown by responders (patients with a reduction of apnea-hypopnea index by more than 50%), there were no significant changes in non-responders. However, retroglossal airway space did not significantly increase with an MAD even in responders. CONCLUSIONS: Improvement of OSA with an MAD can be predicted with soft palate-associated upper airway changes shown in cephalometry.

Diels-Alder and Stille Coupling Approach for the Short Protecting-Group-Free Synthesis of Mycophenolic Acid, Its Phenylsulfenyl and Phenylselenyl Analogues, and Reactive Oxygen Species (ROS) Probing Capacity in Water.

A short, protecting-group-free synthesis is achieved. The synthesis is step-efficient and general. A Diels-Alder and Stille cross-coupling approach includes key transformations, allowing for a competitive synthesis which involves a rare halophenol Stille cross-coupling study. The phenylselenyl and phenylsulfenyl analogues were prepared as novel compounds in good overall yield. The applicability of one of the intermediates as a potential probe for reactive oxygen species (ROS) in water is investigated.

Tonsillectomy increases the risk of retropharyngeal and parapharyngeal abscesses in adults, but not in children: A national cohort study.

OBJECTIVES: The purpose of this study is to evaluate the risk of retropharyngeal and parapharyngeal abscesses (deep neck infection) after tonsillectomy in Koreans using national cohort data. METHODS: Using the national cohort study from the Korean Health Insurance Review and Assessment Service, participants who had undergone a tonsillectomy (5,299) and control participants (21,196) were selected and matched 1:4 (for age, sex, income, region of residence, and pre-operative upper respiratory infection visits). The Cox-proportional hazard model was used. A crude model and an adjusted model for age, sex, income, region of residence, hypertension, diabetes, and dyslipidemia were used in this analysis. For the subgroup analyses, the participants were divided into 2 groups: children (≤ 14 years old) and adolescents and adults (≥ 15 years old). RESULTS: The adjusted hazard ratio of deep neck infection after tonsillectomy was 1.43 (95% confidence interval, CI = 1.18-1.72, P < 0.001). In subgroup analysis, this ratio was 1.12 (95% CI = 0.86-1.47, P = 0.390) in children and 1.87 (95% CI = 1.43-2.45, P < 0.001) in adolescents and adults. The crude hazard ratios were almost the same as the adjusted ratios. CONCLUSION: The risk of deep neck infection was higher in the tonsillectomy group. The subgroup analysis showed a similar finding in the adolescent and adult group but not in the child group.

Chronic rhinosinusitis increases the risk of hemorrhagic and ischemic stroke: A longitudinal follow-up study using a national sample cohort.

BACKGROUND: Several studies have reported that chronic rhinosinusitis (CRS) increases the risk of stroke. The aim of this study is to elucidate the putative association between CRS and stroke (ischemic or hemorrhagic) using large population-based national health insurance data. METHODS: Using the national cohort study from the Korean Health Insurance Review and Assessment Service, CRS patients (n = 22,959) and control participants (n = 91,836) were selected and matched at a rate of 1:4 (age, sex, income, region, hypertension, diabetes, and dyslipidemia). A Cox-proportional hazard model was used to analyze the hazard ratio (HR) of CRS for hemorrhagic stroke and ischemic stroke. We divided the participants according to age and gender for the subgroup analysis. RESULTS: The HR for hemorrhagic and ischemic stroke was significantly increased in the CRS patients compared to that in the controls (adjusted HR = 2.43, 95% confidence interval [CI] = 2.10-2.80 for hemorrhagic stroke; adjusted HR = 1.76, 95% CI = 1.61-1.92 for ischemic stroke) after adjusting for age, sex, income, region of residence, hypertension, diabetes, dyslipidemia, ischemic heart disease, migraine, chronic kidney disease, depression, sleep disorder, and chronic obstructive pulmonary disorder. In the subgroup analysis, the HR of hemorrhagic stroke was significantly increased in the CRS group regardless of age and gender. The HR of ischemic stroke was also significantly increased in all subgroups of the CRS group. CONCLUSION: CRS consistently increased the risk of ischemic and hemorrhagic stroke regardless of age and gender.