GJB2 p.V37I Mutation Associated With Moderate Nonsyndromic Hearing Loss in an Adult Taiwanese Population.

BACKGROUND: Gap junction protein beta 2 ( GJB2 ) p.V37I mutations are the most important hereditary cause of sensorineural hearing loss (SNHL) in Taiwan. Hearing outcomes are associated with hearing levels at baseline and the duration of follow-up. However, the audiological features of GJB2 p.V37I mutations in the adult population are unknown. The objectives of the present study were to investigate the audiological features, progression rate, and allele frequency of GJB2 p.V37I mutations among an adult Taiwanese population. METHODS: Subjects of this case-control study were chosen from 13,580 participants of the Taiwan Precision Medicine Initiative. The genetic variations of GJB2 p.V37I were determined by polymerase chain reaction. We analyzed existing pure-tone threshold data from 38 individuals who were homozygous or compound heterozygotes for GJB2 p.V37I, 129 who were heterozygotes, and 602 individuals who were wild-type. Phenome-wide association studies (PheWAS) analysis was also performed to identify phenotypes associated with GJB2 p.V37I. RESULTS: The minor allele frequency of GJB2 p.V37I was 0.92% in our study population. The mean hearing level of participants with a p.V37I mutation indicated moderate to severe hearing loss with 38.2% ± 22.3% binaural hearing impairment. GJB2 p.V37I was associated with an increased risk of hearing disability (odds ratio: 21.46, 95% confidence interval: 8.62 to 53.44, p < 0.001) in an autosomal recessive pattern. In addition, PheWAS discovered a significant association between GJB2 p.V37I and fracture of the humerus. GJB2 p.V37I is a pathogenic and prevalent variant of SNHL among the adult population. CONCLUSIONS: The present study recommends patients with known GJB2 p.V37I mutations receive regular audiometric evaluation and genetic counseling. Early assistive listening device intervention is suggested to improve the quality of hearing.

Effect of Functional Endoscopic Sinus Surgery on Gustatory Function in Patients With Chronic Rhinosinusitis.

OBJECTIVES: In this study, we investigated the effect of functional endoscopic sinus surgery (FESS) on gustatory function in patients with chronic rhinosinusitis (CRS). METHODS: Forty-three patients with CRS who underwent FESS were included in this study. Prior to FESS and 3 months after surgery, the severity of rhinosinusitis was assessed using the Taiwanese version of the 22-item SNOT (SNOT-22), endoscopic examination, and acoustic rhinometry. The olfactory function was evaluated using the phenylethyl alcohol odor detection threshold test and the traditional Chinese version of the University of Pennsylvania Smell Identification Test, and the gustatory function was evaluated using the whole mouth suprathreshold taste test (WMTT) and the taste quad test (TQT). Subgroup analyses were performed based on CRS phenotypes and endotypes. RESULTS: The SNOT-22 significantly improved 3 months after FESS for all patients with CRS. The endoscopic score and olfactory function significantly improved in patients with eosinophilic CRS and in patients with nasal polyps (CRSwNP). The WMTT sweet and bitter scores were significantly lower after FESS in CRSwNP, but the TQT sweet score was significantly higher in patients without nasal polyps. In addition, patients with noneosinophilic CRS had significantly decreased WMTT and salty scores 3 months after FESS. CONCLUSION: Our results showed that the effect of FESS on gustatory function of patients with CRS was different with the different testing procedures, the association with nasal polyps, and the underlying inflammatory patterns.

Validation of the local applicability of the 'TIB' Olfactory Test Device in the era of COVID-19.

OBJECTIVE: To evaluate the validity and test-retest reliability of the novel 'TIB' Olfactory Test Device (TIB) and to determine its normative values. METHODS: The study stratified the study subjects into normosmic, hyposmic and anosmic groups according to their olfactory function. The olfactory function of the subjects was evaluated using both the traditional Chinese version of the University of Pennsylvania of Smell Identification Test (UPSIT-TC) and the TIB. The normosmic group was used to retest with the UPSIT-TC and TIB at an inter-test interval of at least 7 days. The cut-off scores of TIB among the three different groups were determined by receiver operating characteristic curve analysis. RESULTS: This study enrolled 180 subjects: 60 in each group. The mean scores of TIB were 44.1 for the normosmic group, 27.5 for the hyposmic group and 10.9 for the anosmic group. The TIB scores were significantly different across the three groups. There was a significant correlation between the first and second TIB tests (r = 0.506). The cut-off scores were 41 for normosmic subjects and 24 for hyposmic subjects. CONCLUSION: The validity and test-retest reliability results suggest that the TIB is an appropriate olfactory test for the Taiwanese population.

A KCNQ4 c.546C>G Genetic Variant Associated with Late Onset Non-Syndromic Hearing Loss in a Taiwanese Population.

Clinical presentation is heterogeneous for autosomal dominant nonsyndromic hearing loss (ADNSHL). Variants of KCNQ4 gene is a common genetic factor of ADNSHL. Few studies have investigated the association between hearing impairment and the variant c.546C>G of KCNQ4. Here, we investigated the phenotype and clinical manifestations of the KCNQ4 variant. Study subjects were selected from the participants of the Taiwan Precision Medicine Initiative. In total, we enrolled 12 individuals with KCNQ4 c.546C>G carriers and 107 non-carriers, and performed pure tone audiometry (PTA) test and phenome-wide association (PheWAS) analysis for the patients. We found that c.546C>G variant was related to an increased risk of hearing loss. All patients with c.546C>G variant were aged >65 years and had sensorineural and high frequency hearing loss. Of these patients, a third (66.7%) showed moderate and progressive hearing loss, 41.7% complained of tinnitus and 16.7% complained of vertigo. Additionally, we found a significant association between KCNQ4 c.546C>G variant, aortic aneurysm, fracture of lower limb and polyneuropathy in diabetes. KCNQ4 c.546C>G is likely a potentially pathogenic variant of ADNSHL in the elderly population. Genetic counseling, annual audiogram and early assistive listening device intervention are highly recommended to prevent profound hearing impairment in this patient group.