Background: Few studies have reported on the etiology, severity, or device usage of unilateral sensorineural hearing loss (UHL) compared to bilateral hearing loss. Therefore, this study investigated the characteristics of UHL in adults and children. Methods: We performed a survey using questionnaires for secondary and tertiary otolaryngology institutions. Results: We included 15,981 patients (1549 children and 14,432 adults) from 196 institutions with otolaryngology residency programs and 2844 patients (336 children and 2508 adults) from 27 institutions with board members of the Japan Audiology Society. The latter submitted audiological data. Among children, most diagnoses were made at age 0. Approximately half of them had profound hearing loss, and 37 children (2.2%) used hearing devices. Among adults, the number of cases increased with age, but decreased when people reached their 80s and 90s. More than half of them had moderate hearing loss. Sudden sensorineural hearing loss was the most common cause of UHL of all ages; 4.4% of UHL patients used hearing devices, and most of the device users (98.6%) selected a conventional hearing aid. Conclusions: Hearing aid use is limited in children and adults with UHL in Japan. There could be many candidates with UHL for intervention such as a cochlear implant.

Background: Bilateral vestibulopathy (BVP) causes chronic postural instability refractory to treatments, leading to a reduced quality of life and increased risk of falls. However, the severity of postural instability varies considerably among individuals with BVP. Objective: This study aimed to identify clinical factors associated with postural instability in patients with BVP. Methods: Fifty-two patients with BVP (26 males, 26 females; mean age: 57.0±15.5 y) were enrolled. Associations between postural stability assessed by center of pressure (COP) velocity during posturography (4 conditions: eyes open, eyes closed, eyes open with foam rubber, and eyes closed with foam rubber) and clinical parameters were examined using the Spearman rank correlation. Extent of vestibular dysfunction was quantified as the number of abnormal vestibular end organs assessed by the video head impulse test and vestibular evoked myogenic potentials. Multiple regression analyses were performed to identify factors associated with COP velocity, including extent of vestibular dysfunction, Dizziness Handicap Inventory (DHI), and Hospital Anxiety and Depression Scale (HADS) scores. Results: Correlation analyses of COP velocity measured under the 4 posturography conditions revealed significant positive correlations with age and the number of abnormal vestibular function tests. In contrast, no significant correlations were observed with illness duration, caloric test results, DHI, or HADS. Multiple regression analyses demonstrated that the number of abnormal vestibular function tests was the only factor significantly associated with COP velocity across all 4 posturography conditions. Conclusions: In patients with BVP, postural instability is positively correlated with the number of abnormal vestibular end organs. Conversely, demographic factors (age, sex), subjective level of disability (DHI score), and psychological status (HADS score) are weakly, if at all, correlated with postural instability.

Fluorouracil (FU) exerts its antitumor activity by inhibiting folate-mediated one-carbon metabolism. Evidence that folate may play a role in the carcinogenic process via folate-mediated one-carbon metabolism has given rise to the hypothesis that pre-diagnostic folate intake may induce heterogeneous chemosensitivity to FU-containing induction chemotherapy (IC) in head and neck cancer. To assess this hypothesis, we conducted a cohort study to investigate whether the association between prediagnostic dietary folate intake and cancer survival differed between treatment regimens with and without FU-containing IC in 504 cases of locally advanced (stage III/IV) HNSCC, using an epidemiologic database combined with clinical data. In total, 240 patients were treated with FU-containing IC followed by definitive treatment, and 264 patients were treated with definitive treatment alone. Definitive treatment is defined as (1) the surgical excision of a tumor with clear margins, with or without neck lymph node dissection; or (2) radiotherapy with or without chemotherapy. In the overall cohort of the FU-containing IC group, a higher folate intake was significantly associated with better overall survival (adjusted hazard ratios (HRs) for the highest compared to the lowest folate tertiles (HR_T3-T1) = 0.42, 95%CI, 0.25–0.76, P_trend = 0.003). Conversely, no apparent association between prediagnostic folate intake and survival was observed with definitive treatment alone (HR_T3-T1: 0.83, 95%CI, 0.49–1.42, P_trend = 0.491)). A consideration of the cumulative dose of FU-containing IC showed that the survival impact of prediagnostic folate intake differed statistically significantly by treatment regimen (Pinteraction = 0.012). In conclusion, an association between prediagnostic folate intake and HNSCC survival significantly differed by FU-containing IC. This finding indicates that in the carcinogenic process, folate status causes HNSCC to be heterogenous in terms of one-carbon metabolism.