Importance of small vessel disease as a possible cause of sudden sensorineural hearing loss.

OBJECTIVE: Vascular disease like small-vessel disease (SVD) is the most likely cause among the potential causes of Sudden sensorineural hearing loss (SSNHL). Understanding the relationship between SVD and SSNHL is crucial for developing effective prevention and treatment strategies. To confirm the relationship between SVD and SSNHL, the effect of SVD is confirmed by focusing on the duration and recurrence of SSNHL. METHODS: This article reports a retrospective observational study that investigated the relationship between SVD and SSNHL using the South Korea Health Insurance Review and Assessment Service (HIRA) database from 2010 to 2020. This retrospective observational study included 319,569 SSNHL patients between 2010 and 2020. RESULTS: Participant demographics were controlled using Propensity Score Matching. The hazard ratios (HR) for the effect of SVD on the duration of SSNHL were 1.045 for the group with SVD before the onset of SSNHL and 1.234 for the group with SVD after the onset of SSNHL. SVD was statistically significant for the recurrence of SSNHL, with an odds ratio of 1.312 in the group with SVD compared to the group without SVD. The HR for the period until a recurrence in the group with SVD was 1.062. CONCLUSIONS: The study identified SVD as a possible cause of SSNHL and found that the duration of SSNHL increased only in the presence of SVD. SVD also affected the recurrence of SSNHL, with the recurrence rate being 1.312 times higher in the group with SVD.

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.

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.

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.

Improving Accuracy and Reliability of Hearing Tests: Measurement Standards for Audiometric Devices.

Pure-tone audiometry, using an audiometer, is the fundamental hearing test for diagnosing hearing loss. The requirements of the devices and the detailed process for calibrating the related equipment are described in international standards. However, traceable calibration and uncertainty evaluation processes are not widely accepted or applied to the qualification and maintenance of audiometric equipment. Here, we briefly review standard measurement systems for audiometric devices and introduce their calibration procedures. The uncertainty of each calibration process was investigated, and its impact on hearing test results was considered. Our findings show that the traceability of each procedure can be secured, satisfying the uncertainty requirement and being sufficiently smaller than the permissible deviation from the audiometer requirement. To guarantee the objectivity and reliability of hearing tests and maintain low uncertainty, close cooperation and mutual understanding between the metrology field and the medical community are necessary.