Clinical characteristics of the "Gap" between the prevalence and incidence of hearing loss using National Health Insurance Service data.

OBJECTIVES: Hearing loss is the inability to hear speech or sounds well, owing to a number of causes. This study aimed to simultaneously determine the prevalence, incidence, and the Gap between them in hearing loss in South Korean patients at the same point in time as well as to identify patients who have not recovered from hearing loss. METHODS: We examined the prevalence and incidence of patients diagnosed with hearing loss in the National Health Insurance Service database over an 11-year period from 2010 to 2020. The difference between the prevalence and the incidence was defined in this study as the term "Gap". Gap is the number of patients converted into the number of patients per 100,000 people by subtracting the incidence from the prevalence. Clinical characteristics such as sex and age per 100,000 individuals were examined. RESULTS: As of 2020, the domestic prevalence obtained in this study was 1.84%, increasing annually, and the prevalence increased with age to 4.10% among those over 60. The domestic incidence was 1.57%, increasing annually, and the incidence increased with age to 3.36% for those over 60s. The Gap was 0.27%, showing a steady increase from 2011 to 2020 with a corresponding increase in insurance benefit expenses. CONCLUSION: To fully understand the burden of hearing loss and develop effective prevention and treatment strategies, it is important to measure the Gap between its prevalence and incidence. This Gap means a lot because hearing loss is an irreversible disease. Gap represents patients who have already been diagnosed with hearing loss and are being diagnosed every year, indicating that the number of patients who do not recover is increasing. In other words, the increase in Gap meant that there were many patients who constantly visited the hospital for diagnosis of hearing loss.

Vitamin D supplementation in preventing the recurrence of benign paroxysmal positional vertigo.

Objective: To evaluate the effect of vitamin D supplementation on the recurrence rate of benign paroxysmal positional vertigo (BPPV). Methods: A single-center, prospective, double-blind, placebo-controlled, parallel-group randomized controlled trial was conducted between November 2018 and May 2020. After successful treatment with canalith repositioning maneuvers, patients diagnosed with BPPV were randomized to either the vitamin D (n = 20) or placebo (n = 18) group. Only patients with serum vitamin D levels <20 ng mL-1 were included. The vitamin D group received 7000 IU of vitamin D weekly for a year, while the placebo group received a matching placebo drug. The final endpoint was the BPPV recurrence rate and correlation with serum vitamin D levels after 6 and 12 months in both groups. Results: Among 38 patients, 37 were followed up for 6 months and 30 for 12 months. Significantly higher serum vitamin D levels were observed in the vitamin D group compared to the placebo group at both the 6-month and 1-year follow-ups (p < .001 at each timepoint). The recurrence rate was lower in the vitamin D group than in the placebo group after 6 months (p = .008) and 1 year (p = .003). Conclusion: Vitamin D supplementation, in the absence of calcium, may be beneficial for patients prone to recurrent BPPV episodes, particularly when serum vitamin D levels are suboptimal (PRE20181024-001, Clinical Research Information Service, South Korea). Level of Evidence: 1b.

Trends in Distributions of Hearing Threshold Levels by Ages: A Comparison of the ISO 7029 and Newly Available Country-Specific Data.

Hearing thresholds provide essential information and references about the human auditory system. This study aimed to identify changing trends in distributions of hearing threshold levels across ages by comparing the International Organization for Standardization (ISO) 7029 and newly available data after publishing ISO 7029. To compare ISO 7029 and newly available hearing threshold data after publishing ISO 7029, four country-specific datasets that presented average hearing threshold levels under conditions similar to ISO 7029 were utilized. For frequencies between 125 Hz and 8,000 Hz, the deviations of hearing threshold values by ages from the hearing threshold of the youngest age group for each data point were utilized. For frequencies from 9,000 Hz to 12,500 Hz, the median threshold information was utilized. Hearing threshold data reported after publishing ISO 7029 from the four countries were mostly similar to the ISO 7029 data but tended to deviate in some age groups and sexes. As national hearing threshold trends change, the following ISO 7029 revision suggests the need to integrate hearing threshold data from different countries.

Effect of changes in the hearing aid subsidy on the prevalence of hearing loss in South Korea.

Objectives: South Korea's National Health Insurance has provided hearing aids to registered individuals with hearing disabilities since 1989. In 2015, hearing aid subsidies increased to approximately US$1,000. This study aimed to understand hearing loss categories in Korea by analyzing patients between 2010 and 2020 and the effect of the 2015 hearing aid policy change on the prevalence of hearing loss. Methods: The participants were patients registered on the National Health Insurance Service database from 2010 to 2020 with hearing loss. A total of 5,784,429 patients were included in this study. Hearing loss was classified into conductive, sensorineural, and other categories. Patients with hearing loss were classified according to the International Classification of Diseases diagnostic code. Disability diagnosis and hearing aid prescription were defined using the National Health Insurance Disability and Hearing Aid Code. Results: The increase in hearing aid prescriptions and hearing disability registrations following the subsidy increase impacts hearing loss prevalence. Hearing aid prescription and hearing disability were found to have an effect on increasing hearing loss prevalence in univariate and multivariate analyses. The r-value of each analysis exceeded 0.95. Other hearing losses increased rapidly after the increased subsidy. Conclusion: A hearing-impaired individual must be diagnosed with a hearing disability and prescribed a hearing aid to receive the subsidy. The prevalence of hearing loss was affected by increased hearing disabilities following changes in the hearing aid subsidy and the number of people prescribed hearing aids. Therefore, caution should be exercised when studying hearing loss prevalence over mid-long-term periods.

Improving Accuracy and Reliability of Hearing Tests: An Exploration of International Standards.

This study explores the internal standards for hearing tests and benefits of implementing international standard protocols, including the International Organization for Standardization (ISO) and International Electrotechnical Commission (IEC), and discusses how ISO and IEC standards provide a framework for designing, calibrating, assessing hearing test instruments and methods, and exchanging and comparing data globally. ISO and IEC standards for hearing tests improve accuracy, reliability, and consistency of test results by applying standardized methods and environments. Moreover, they promote international harmonization and data interoperability, enabling information exchange and research collaboration. Those standards for hearing tests are beneficial but have challenges and limitations, such as variation in equipment and calibration, lag in updating standards, variation in implementation and compliance, and lack of coverage of clinical aspects, cultural diversity, and linguistic diversity. These affect the quality and interpretation of test results. Adapting ISO or IEC standards locally would improve their applicability and acceptability, while balancing customization and compatibility with global standards.

A situational analysis of ear and hearing care in South Korea using WHO ear and Hearing Care Situation Analysis tool.

Objectives: The WHO emphasizes lifelong management of hearing diseases such as hearing loss and advocates for prevention. The Ear and Hearing Care Situation Analysis (EHCSA) tool was designed by the WHO for assessment and quality improvement of state-led management of hearing loss prevention and management programs. The purpose of this study was to use the EHCSA to assess the ear and hearing management program in Korea and to establish goals consistent with best practices for improving policies and services related to ear and hearing care. Methods: The EHCSA was used as a need assessment of the ear and hearing management services in the country. The EHCSA consists of two sections. Section 1 consists of 41 questions to evaluate health policies and support services. Section 2 consists of 203 questions to evaluate human resources and services of the ear and hearing management sector. Results: There are an estimated 800,000 people with hearing loss in Korea. Policies such as hearing aid support are in place, and outreach services such as free hearing tests are also being actively conducted. In all medical institutions, ear and hearing management treatment and medication prescriptions could be received without barriers. Workers in the fields of ear and hearing management, such as audiologists, language therapists, special education teachers, and sign language interpreters, are specialized and have well-established guidelines for training. Conclusion: Overall, the domestic ear and hearing management sector has confirmed that policies and services are well-prepared in comparison with advanced countries such as the United States, Iran, and China. The use of the EHCSA was functional in collecting data on the current state of domestic ear and hearing management policies and services in Korea, can be used for continuous quality improvement and expansion of medical services, and can be used as a reporting mechanism to the WHO.

Contralateral bone conducted sound wave propagation on the skull bones in fresh frozen cadaver.

The study aimed to investigate the efficient pathway for BC sound transmission by measuring vibrations on the opposite side of the skull bone, referred to as the mastoid position. The realistic contralateral transmission pathway of bone conduction (BC) vibrations is investigated through each osseous structure in the midlines of the fresh-frozen whole head. BC stimulation is applied to the mastoid using a bone vibrator, and acceleration responses are observed on the contralateral mastoid bone and seven midline points of skull bones using triaxial accelerometers. The study finds that the range showing the highest contralateral transmission efficiency of bone vibration is the intermediate frequency range with contralateral direction. Within this range, a significant amplitude of acceleration response is measured at the face-side points and the back and upper parts of the head. The thesis suggests that signal transmission from the specific midline to the mastoid can be more efficient than the conventional configuration of BC from the mastoid to the mastoid.

Dose-escalated radiotherapy for clinically localized and locally advanced prostate cancer.

BACKGROUND: Treatments for clinically localized prostate cancer include radical prostatectomy, external beam radiation therapy, brachytherapy, active surveillance, hormonal therapy, and watchful waiting. For external beam radiation therapy, oncological outcomes may be expected to improve as the dose of radiotherapy (RT) increases. However, radiation-mediated side effects on surrounding critical organs may also increase. OBJECTIVES: To assess the effects of dose-escalated RT in comparison with conventional dose RT for curative treatment of clinically localized and locally advanced prostate cancer. SEARCH METHODS: We performed a comprehensive search using multiple databases including trial registries and other sources of grey literature, up until 20 July 2022. We applied no restrictions on publication language or status. SELECTION CRITERIA: We included parallel-arm randomized controlled trials (RCTs) of definitive RT in men with clinically localized and locally advanced prostate adenocarcinoma. RT was dose-escalated RT (equivalent dose in 2 Gy [EQD2] ≥ 74 Gy, lesser than 2.5 Gy per fraction) versus conventional RT (EQD2 < 74 Gy, 1.8 Gy or 2.0 Gy per fraction). Two review authors independently classified studies for inclusion or exclusion. DATA COLLECTION AND ANALYSIS: Two review authors independently abstracted data from the included studies. We performed statistical analyses by using a random-effects model and interpreted them according to the Cochrane Handbook for Systematic Reviews of Interventions. We used GRADE guidance to rate the certainty of the evidence of RCTs. MAIN RESULTS: We included nine studies with 5437 men in an analysis comparing dose-escalated RT versus conventional dose RT for the treatment of prostate cancer. The mean participant age ranged from 67 to 71 years. Almost all men had localized prostate cancer (cT1-3N0M0). Primary outcomes Dose-escalated RT probably results in little to no difference in time to death from prostate cancer (hazard ratio [HR] 0.83, 95% CI 0.66 to 1.04; I2 = 0%; 8 studies; 5231 participants; moderate-certainty evidence). Assuming a risk of death from prostate cancer of 4 per 1000 at 10 years in the conventional dose RT group, this corresponds to 1 fewer men per 1000 (1 fewer to 0 more) dying of prostate cancer in the dose-escalated RT group. Dose-escalated RT probably results in little to no difference in severe RT toxicity of grade 3 or higher late gastrointestinal (GI) toxicity (RR 1.72, 95% CI 1.32 to 2.25; I2 = 0%; 8 studies; 4992 participants; moderate-certainty evidence); 23 more men per 1000 (10 more to 40 more) in the dose-escalated RT group assuming severe late GI toxicity as 32 per 1000 in the conventional dose RT group. Dose-escalated RT probably results in little to no difference in severe late genitourinary (GU) toxicity (RR 1.25, 95% CI 0.95 to 1.63; I2 = 0%; 8 studies; 4962 participants; moderate-certainty evidence); 9 more men per 1000 (2 fewer to 23 more) in the dose-escalated RT group assuming severe late GU toxicity as 37 per 1000 in the conventional dose RT group. Secondary outcomes Dose-escalated RT probably results in little to no difference in time to death from any cause (HR 0.98, 95% CI 0.89 to 1.09; I2 = 0%; 9 studies; 5437 participants; moderate-certainty evidence). Assuming a risk of death from any cause of 101 per 1000 at 10 years in the conventional dose RT group, this corresponds to 2 fewer men per 1000 (11 fewer to 9 more) in the dose-escalated RT group dying of any cause. Dose-escalated RT probably results in little to no difference in time to distant metastasis (HR 0.83, 95% CI 0.57 to 1.22; I2 = 45%; 7 studies; 3499 participants; moderate-certainty evidence). Assuming a risk of distant metastasis of 29 per 1000 in the conventional dose RT group at 10 years, this corresponds to 5 fewer men per 1000 (12 fewer to 6 more) in the dose-escalated RT group developing distant metastases. Dose-escalated RT may increase overall late GI toxicity (RR 1.27, 95% CI 1.04 to 1.55; I2 = 85%; 7 studies; 4328 participants; low-certainty evidence); 92 more men per 1000 (14 more to 188 more) in the dose-escalated RT group assuming overall late GI toxicity as 342 per 1000 in the conventional dose RT group. However, dose-escalated RT may result in little to no difference in overall late GU toxicity (RR 1.12, 95% CI 0.97 to 1.29; I2 = 51%; 7 studies; 4298 participants; low-certainty evidence); 34 more men per 1000 (9 fewer to 82 more) in the dose-escalated RT group assuming overall late GU toxicity as 283 per 1000 in the conventional dose RT group. Based on long-term follow-up (up to 36 months), dose-escalated RT may result or probably results in little to no difference in the quality of life using 36-Item Short Form Survey; physical health (MD -3.9, 95% CI -12.78 to 4.98; 1 study; 300 participants; moderate-certainty evidence) and mental health (MD -3.6, 95% CI -83.85 to 76.65; 1 study; 300 participants; low-certainty evidence), respectively. AUTHORS' CONCLUSIONS: Compared to conventional dose RT, dose-escalated RT probably results in little to no difference in time to death from prostate cancer, time to death from any cause, time to distant metastasis, and RT toxicities (except overall late GI toxicity). While dose-escalated RT may increase overall late GI toxicity, it may result, or probably results, in little to no difference in physical and mental quality of life, respectively.

Epidemiology of idiopathic sudden sensorineural hearing loss in the era of big data.

OBJECTIVES: Idiopathic sudden sensorineural hearing loss (ISSNHL) is a medical emergency, and delayed treatment can have permanent sequelae. However, the etiology of ISSNHL is diverse and unclear; thus, it is idiopathic. To develop an insight into this condition, patients with ISSNHL must be clearly identified. We propose an operational definition for the unambiguous identification of ISSNHL patients. Patients are identified through suggested definitions, and prevalence and general information are investigated. METHODS: A retrospective study of patients with ISSNHL was performed using the Health Insurance and Review Assessment-National Patient Sample from 2009 to 2016. To present a new operational definition, a systematic review was conducted for studies on ISSNHL from January 2007 to June 2021. After constructing several operant definitions using the conditions that can specify patients with ISSNHL in big data, we compared each definition to propose an operational definition. RESULTS: The important conditions required to classify patients with ISSNHL using big data were the International Classification of Diseases (ICD)-10 code, number of pure tone audiometry (PTA) tests, and whether steroids were prescribed. Among them, those who had undergone PTA tests more than twice could be clearly identified as patients with ISSNHL. CONCLUSION: As the use of big data becomes smoother, research using national medical data is being conducted; however, the results of the studies may vary depending on how a patient with ISSNHL is classified. Clear identification of patients with ISSNHL will be beneficial for better management of this condition.

Selectively Enhanced Electrocatalytic Oxygen Evolution within Nanoscopic Channels Fitting a Specific Reaction Intermediate for Seawater Splitting.

Abundant availability of seawater grants economic and resource-rich benefits to water electrolysis technology requiring high-purity water if undesired reactions such as chlorine evolution reaction (CER) competitive to oxygen evolution reaction (OER) are suppressed. Inspired by a conceptual computational work suggesting that OER is kinetically improved via a double activation within 7 Å-gap nanochannels, RuO2 catalysts are realized to have nanoscopic channels at 7, 11, and 14 Å gap in average (dgap ), and preferential activity improvement of OER over CER in seawater by using nanochanneled RuO2 is demonstrated. When the channels are developed to have 7 Å gap, the OER current is maximized with the overpotential required for triggering OER minimized. The gap value guaranteeing the highest OER activity is identical to the value expected from the computational work. The improved OER activity significantly increases the selectivity of OER over CER in seawater since the double activation by the 7 Å-nanoconfined environments to allow an OER intermediate (*OOH) to be doubly anchored to Ru and O active sites does not work on the CER intermediate (*Cl). Successful operation of direct seawater electrolysis with improved hydrogen production is demonstrated by employing the 7 Å-nanochanneled RuO2 as the OER electrocatalyst.

Deep Learning Techniques for Ear Diseases Based on Segmentation of the Normal Tympanic Membrane.

OBJECTIVES: Otitis media is a common infection worldwide. Owing to the limited number of ear specialists and rapid development of telemedicine, several trials have been conducted to develop novel diagnostic strategies to improve the diagnostic accuracy and screening of patients with otologic diseases based on abnormal otoscopic findings. Although these strategies have demonstrated high diagnostic accuracy for the tympanic membrane (TM), the insufficient explainability of these techniques limits their deployment in clinical practice. METHODS: We used a deep convolutional neural network (CNN) model based on the segmentation of a normal TM into five substructures (malleus, umbo, cone of light, pars flaccida, and annulus) to identify abnormalities in otoscopic ear images. The mask R-CNN algorithm learned the labeled images. Subsequently, we evaluated the diagnostic performance of combinations of the five substructures using a three-layer fully connected neural network to determine whether ear disease was present. RESULTS: We obtained the receiver operating characteristic (ROC) curve of the optimal conditions for the presence or absence of eardrum diseases according to each substructure separately or combinations of substructures. The highest area under the curve (0.911) was found for a combination of the malleus, cone of light, and umbo, compared with the corresponding areas under the curve of 0.737-0.873 for each substructure. Thus, an algorithm using these five important normal anatomical structures could prove to be explainable and effective in screening abnormal TMs. CONCLUSION: This automated algorithm can improve diagnostic accuracy by discriminating between normal and abnormal TMs and can facilitate appropriate and timely referral consultations to improve patients' quality of life in the context of primary care.

Learning curve comparable study of microscopic and endoscopic type 1 tympanoplasty.

OBJECTIVES: The comparative efficacy of microscopic tympanoplasty (MT) and endoscopic tympanoplasty (ET) has been widely studied to some extent through meta-analyses. However, most studies on learning curve comparisons between the two surgeries were performed by experienced ET surgeons. We compared the surgical outcomes of MT and ET and evaluated the difference of learning curve between ET and MT performed by a single unskilled, in both MT and ET, surgeon. DESIGN: A total of 91 patients underwent ET and MT at a tertiary hospital. We reviewed the patients' medical records and analyzed all findings, including otoscopic pictures, pure tone audiometry (PTA) before and after surgery, and operation records. All operations were performed by a single otologist who had an experience of a year of otology fellowship at a tertiary university hospital. We compared the demographic and clinical characteristics, including age, sex, admission duration, and audiological outcomes before and after surgery. We also assessed the difference in the decrease in operation time. RESULTS: Among 91 patients, 44 were in the ET group and 47 were in the MT group. The mean age was 51.15 years, and 37 (40.7%) were men. Eighty-two (90.1%) patients were administered local anesthesia. Graft failure was observed in 19 (20.9%) patients, and the mean postoperative follow-up duration was 66.42 days. There were no statistically significant differences in age, sex, affected side, graft failure rate, and operation time between the ET and MT groups. There was a significant improvement in air conduction hearing and air-bone gap after surgery in both groups. Bone conduction hearing did not change before and after the surgery in either group. However, the improvement in air condition and reduction in the air-bone gap did not differ between the two groups. Multivariate linear regression analysis showed that there were no significant variables that affected operation time among age, sex, operation method (ET or MT), anesthesia, graft material, and technique. The spline regression analysis showed the decrease in operative time in ET was significantly faster than MT in the period from 8th to 19th cases. CONCLUSIONS: The surgical outcomes of ET are comparable to those of MT in terms of operation time, graft uptake, and postoperative hearing results, even in surgeons who are not experienced with both MT and ET. The operation time of ET was longer than that of MT in the early phase, and the decrease in the operating time was significantly faster in ET than in MT. Both MT and ET reached a plateau in the operation time, and this plateau appeared to be similar in both surgeries.

Protection of Hearing Loss in Ototoxic Mouse Model Through SPIONs and Dexamethasone-Loaded PLGA Nanoparticle Delivery by Magnetic Attraction.

Background: Ototoxicity currently has no available treatment other than medication withdrawal as soon as toxicity is suspected. The human inner ear organs have little potential for regeneration; thus, ototoxicity-induced hair cell injury is deemed permanent. Dexamethasone (Dexa) is a synthetic steroid analog that has significant potential for otoprotection in the treatment of various inner ear diseases; however, its low absorption into the inner ear prevents significant recovery of function. Nanoparticles facilitate targeted drug delivery, stabilize drug release, and increase half-life of the drug. Methods: This study aimed to develop poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded superparamagnetic iron oxide nanoparticles (SPIONs) and Dexa (PSD-NPs) to control localized drug delivery by magnetic attraction in the treatment of ototoxicity-induced hearing loss. PSD-NPs and without SPIONs (PD-NPs) were prepared using a nanoprecipitation method. Results: Using an inner ear simulating system, we confirmed that PSD-NPs has an otoprotective effect in organotypic culture that is enhanced by magnetic attraction. PSD-NPs delivered via intrabullar injection in a magnetic field penetrated the inner ear and prevented hearing loss progression to a greater degree than equivalent doses of Dexa or PSD-NPs alone (day 28: ototoxic: 80.0 ± 0.0 dB; Dexa 100: 60.0 ± 15.5 dB; PSD 100: 50.0 ± 8.2 dB; PSD 100 with magnet: 22.5 ± 5.0 dB; P < 0.05). The protective effects were confirmed in various in vivo and in vitro models of ototoxicity. Conclusion: Our findings suggest that SPIONs with Dexa and magnetic field application prevent the progression of ototoxicity-induced hearing loss through anti-apoptotic mechanisms in the inner ear.

Comparison of Auditory Outcomes between Inpatient- and Outpatient-Based Treatment in Sudden Sensorineural Hearing Loss.

Objective: The primary treatment for sudden hearing loss is high-dose steroid therapy. In some countries, hospitalization has been taken for granted. Although most countries appear to treat sudden hearing loss on an outpatient basis, some other countries have considered hospitalization as necessary. Only a few studies have been conducted on the effect of hospitalization on hearing outcomes. Therefore, we compared the hearing outcome of inpatient- and outpatient-based treatments to determine whether hospitalization affects the recovery of sudden hearing loss. Methods: We conducted a retrospective case review of patients diagnosed with sudden sensorineural hearing loss (SSNHL). In total, 439 patients with SSNHL were enrolled and categorized as either inpatients (group I) or outpatients (group O). Pure-tone audiometry was initially performed before the treatment and 3 months post-treatment. "Recovery" was defined as a hearing gain of 15 dB HL and a final hearing of better than 25 dB. "No recovery" was defined as an improvement of hearing gain of <15 dB 3 months after treatment. To exclude the effect of the level of pretreatment hearing loss, we divided the patients into three subgroups based on their hearing level: <40 dB, 40−70 dB, and >70 dB. To assess the effect of the treatment modality, the patients were divided into three treatment subgroups: systemic steroids (SS), intratympanic steroids (ITS), and a combination of both (SS and ITS). Results: The pretreatment hearing level was significantly higher in group I (61.5 ± 25.4 dB) than in group O (50.3 ± 23.0 dB; p < 0.05). The hearing gain was significantly higher in group I (33.3 ± 24.4 dB) than in group O (24.0 ± 21.8 dB; p < 0.05). The "Recovery" ratio was significantly higher in group I (70.2%) than in group O (63.1%) (p < 0.05). A repeated measures ANOVA was performed to assess the statistical differences between hospitalization, treatment modalities, and pretreatment subgroups. The inpatient group showed a significant hearing improvement in all SSNHL patients (p < 0.05). There was a significant hearing improvement in the inpatient group with pretreatment hearing <40 and 40−70 dB (p < 0.05). There was no significant difference between the inpatient and outpatient groups in pretreatment hearing >70 dB (p > 0.05). Conclusions: This retrospective study showed that inpatient treatment for sudden hearing loss is more beneficial for hearing improvement than outpatient treatment. The positive effect of inpatient treatment appears to be significant in patients with a pretreatment hearing level of 70 dB or less.

Relationship between Nutrient Intake and Hearing Loss According to the Income Level of Working-Aged Adults: A Korean National Health and Nutrition Survey.

The relationship between hearing impairment and nutrition has been extensively investigated; however, few studies have focused on this topic in working-age adults by income level. Herein, we aimed to determine the differences in hearing impairment among working-age adults by income level and identify the nutritional factors that affect hearing loss in various socioeconomic groups. Seven-hundred-and-twenty participants had hearing impairment, while 10,130 had normal hearing. After adjustment for propensity score matching, income and smoking status were identified as significant variables. By assessing the relationship between hearing impairment and nutrient intake by income level using multiple regression analyses, significant nutrients differed for each income category. Carbohydrate and vitamin C levels were significant in the low-income group; protein, fat, and vitamin B1 levels were significant in the middle-income group; and carbohydrates were significant in the high-income group. Income was significantly associated with hearing impairment in working-age adults. The proportion of individuals with hearing impairment increased as income decreased. The association between hearing impairment and nutritional intake also differed by income level. Our findings may enable the establishment of health policies for preventing hearing impairment in working-age adults by income level.

Recurrence Rate and Risk Factors of Recurrence in Benign Paroxysmal Positional Vertigo: a Single-Center Long-Term Prospective Study With a Large Cohort.

OBJECTIVE: This study aimed to assess the long-term recurrence rate and correlations between recurrence and potential risk factors in patients with benign paroxysmal positional vertigo (BPPV). DESIGN: A total of 548 consecutive patients who demonstrated typical posterior or horizontal BPPV between January 2010 and December 2012 were included in this prospective study. All patients were contacted by phone every 6 months for 5 years and were asked to revisit the clinic when they experienced positional vertigo to be reexamined for recurrence. Recurrence of BPPV was defined as having positional vertigo and nystagmus confirmed following a symptom-free period of at least 7 days after complete resolution. We assessed the 5-year recurrence rate of BPPV, and the time point of recurrence in all patients as well as the risk factors of BPPV recurrence, including the clinical characteristics, therapeutic results of BPPV, and various comorbidities. RESULTS: Among the 548 patients, 121 (22.1 %) had at least one recurrence. Of these, 78 patients (54.5%) had only one recurrence within 5 years, while 43 (45.5%) patients experienced two or more recurrences. A recurrence occurred within 1 year in 82 patients (67.8%). The Cox proportional hazard ratio analysis found that head trauma (p = 0.015), Meniere's disease (p = 0.016), the number of canalith repositioning procedures performed (p = 0.037), and the number of previous vertigo attacks (p = 0.038) were significant risk factors of BPPV recurrence as opposed to hypertension or hyperlipidemia. CONCLUSIONS: The recurrence rate of BPPV was 22.1% at 5 years after the initial treatment. About 70% of recurred patients had a recurrence within 1 year. Head trauma, ipsilateral Meniere's disease, the number of canalith repositioning procedures performed, and the number of previous vertigo attacks were significant risk factors of BPPV recurrence.

The risk of laryngitis with herpes zoster infection: A nested case-control study using data from the Korean National Sample Cohort.

BACKGROUND: Whether herpes zoster infection (HZI) affects laryngitis incidence remains unknown. OBJECTIVE: The purpose of this population-based retrospective study was to analyze the relationship between laryngitis and HZI using data from the Korean Health Insurance Review and Assessment Service-National Sample Cohort. METHODS: This study analyzed 1,197,093 medical claim codes from 2018. Patients with HZI (ICD-10: B02) were retrospectively identified. Laryngeal diseases were defined by ICD-10 codes for five subgroups: 1) malignant disease, 2) benign disease, 3) vocal cord palsy, 4) inflammatory disease, and 5) reflux disease. RESULTS: Among the Korean population older than 20 years, 12,809 experienced HZI. Subjects with HZI were more likely to be older (mean age: 51.54 years vs. 48.06 years, p <0.0001). The proportion of subjects with laryngeal disease was higher in those with HZI than in those without HZI (55.55% vs. 41.37%, p <0.0001). Laryngeal disease was significantly associated with HZI in multiple regression analysis (odds ratio (OR) = 1.77, 95% confidence interval: 1.71-1.84) after adjusting for age, sex, hypertension, diabetes, dyslipidemia, ischemic heart disease, cerebral stroke, and depression. Among laryngeal disease subgroups, inflammatory disease (OR = 1.05; 95% CI: 1.01-1.09) and reflux (OR = 1.20; 95% CI: 1.15-1.25) were associated with HZI. CONCLUSIONS: HZI is independently associated with laryngitis. Results of this study have implications for etiological investigations and prevention strategies for laryngitis.

Alteration of payload in extracellular vesicles by crosstalk with mesenchymal stem cells from different origin.

BACKGROUND: The application of extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) requires customized materials to target disease or cell damage. We hypothesized that EVs exert different inflammatory effects on one recipient cell, although stem cells of different origins in humans have similar payloads. RESULTS: Here, the payload of EVs released by crosstalk between MSCs and human middle ear epithelial cells (HMEECs) extracted from adipose tissue, bone marrow and tonsils significantly increased the level of anti-inflammatory factors. EVs derived from the co-culture medium decreased TNF-α, COX-2, IL-1ß, and IL-6 levels to approximately zero within 3 h in HMEECs. Expression of miR-638 and amyloid-ß A4 precursor protein-binding family A member 2 was analyzed using microarrays and gene ontology analysis, respectively. CONCLUSIONS: In conclusion, stem cells of different origins have different payloads through crosstalk with recipient-specific cells. Inducing specific factors in EVs by co-culture with MSCs could be valuable in regenerative medicine.

Clinical Implications of Horizontal Beating Nystagmus Induced by Dix-Hallpike Test in the Diagnosis of Horizontal Canal Benign Paroxysmal Positional Vertigo.

OBJECTIVES: The purpose of this study was to identify the diverse patterns of nystagmus during the Dix-Hallpike test (DHT) and analyze their clinical significance in horizontal canal benign paroxysmal positional vertigo (HC-BPPV). STUDY DESIGN: Retrospective medical records review. PATIENTS: Two hundred ninety-five patients diagnosed with HC-BPPV. METHODS: Various nystagmus patterns identified during the DHT in patients with HC-BPPV were analyzed. The correlation between the affected side of HC-BPPV and the direction of the horizontal beating nystagmus (HBN) during the DHT was also analyzed. RESULTS: The nystagmus pattern during the DHT in 128 patients with geotropic HC-BPPV demonstrated, direction-changing positional nystagmus on both sides in 48 (37.5%) patients, HBN toward one side in 25 (19.6%) patients, and no nystagmus in 55 (42.9%) patients. In 144 patients with apogeotropic HC-BPPV, 54 (37.5%) patients presented with direction-changing positional nystagmus on both sides, 27 (18.8%) patients presented with HBN toward one side, and 63 (43.7%) patients did not show nystagmus during the DHT. The direction of HBN provoked by the DHT was significantly correlated with the affected side in each subtype of HC-BPPV (geotropic type, p = 0.049; apogeotropic type, p = 0.040; respectively). CONCLUSION: More than half of the patients with HC-BPPV (56.6%) showed HBN during the DHT. When HBN was present during the DHT, it may provide a clue for determining the subtype and affected side in diagnosis of HC-BPPV before performing the supine roll test.