Association of mitochondrial DNA haplogroup and hearing impairment with aging in Japanese general population of the Iwaki Health Promotion Project

Age-related hearing loss (ARHL) is a complex multifactorial disorder. Studies in animals, including mitochondria-mutator mice, and in human suggest that oxidative stress and mitochondrial disturbance play an important role in the pathoetiology of ARHL. Mitochondrial DNA (mtDNA) haplogroups are populations with genetically similar traits, and they have been reported to affect the mitochondrial function of oxidative phosphorylation. To gain further insights into the relationships between mitochondrial haplotypes and the susceptibility to cochlear aging, in this study, we aimed to elucidate how the differences in mtDNA haplogroups may affect ARHL development in Japanese general population. We focused on early onset ARHL, as the same mtDNA haplogroup can show either a negative or positive effect on systemic co-morbidities of ARHL that appear later in life. A total of 1167 participants of the Iwaki Health Promotion Project were surveyed in 2014, and 12 major haplotype groups (D4a, D4b, D5, G1, G2, M7a, M7b, A, B4, B5, N9, and F) were selected for the analysis. A total of 698 subjects aged 30 to 65 years were included in the statistical analysis, and the hearing loss group consisted of 112 males (40.3%) and 111 females (26.4%). Multiple logistic regression analysis showed that the male subjects belonging to haplogroup A had a significantly increased risk of hearing loss, whereas the female subjects belonging to haplogroup N9 had a significantly decreased risk of hearing loss. These results suggested that the mtDNA haplogroup may be an indicator for future risk of morbidity associated with ARHL.

Identification of the First Single GSDME Exon 8 Structural Variants Associated with Autosomal Dominant Hearing Loss

GSDME, also known as DFNA5, is a gene implicated in autosomal dominant nonsyndromic hearing loss (ADNSHL), affecting, at first, the high frequencies with a subsequent progression over all frequencies. To date, all the GSDME pathogenic variants associated with deafness lead to skipping of exon 8. In two families with apparent ADNSHL, massively parallel sequencing (MPS) integrating a coverage-based method for detection of copy number variations (CNVs) was applied, and it identified the first two causal GSDME structural variants affecting exon 8. The deleterious impact of the c.991-60_1095del variant, which includes the acceptor splice site sequence of exon 8, was confirmed by the study of the proband’s transcripts. The second mutational event is a complex rearrangement that deletes almost all of the exon 8 sequence. This study increases the mutational spectrum of the GSDME gene and highlights the crucial importance of MPS data for the detection of GSDME exon 8 deletions, even though the identification of a causal single-exon CNV by MPS analysis is still challenging.

EHealth and Its Role in Supporting Audiological Rehabilitation: Patient Perspectives on Barriers and Facilitators of Using a Personal Hearing Support System With Mobile Application as Part of the EVOTION Study

BackgroundHearing loss is a major public health challenge. Audiology services need to utilise a range of rehabilitative services and maximise innovative practice afforded by technology to actively promote personalized, participatory, preventative and predictive care if they are to cope with the social and economic burden placed on the population by the rapidly rising prevalence of hearing loss. Digital interventions and teleaudiology could be a key part of providing high quality, cost-effective, patient-centred management. There is currently very limited evidence that assesses the hearing impaired patient perspective on the acceptance and usability of this type of technology.AimThis study aims to identify patient perceptions of the use of a hearing support system including a mobile smartphone app when used with Bluetooth-connected hearing aids across the everyday life of users, as part of the EVOTION project.MethodsWe applied a questionnaire to 564 participants in three countries across Europe and analysed the following topics: connectivity, hearing aid controls, instructional videos, audiological tests and auditory training.Key FindingsOlder users were just as satisfied as younger users when operating this type of technology. Technical problems such as Bluetooth connectivity need to be minimised as this issue is highly critical for user satisfaction, engagement and uptake. A system that promotes user-controllability of hearing aids that is more accessible and easier to use is highly valued. Participants are happy to utilise monitoring tests and auditory training on a mobile phone out of the clinic but in order to have value the test battery needs to be relevant and tailored to each user, easy to understand and use. Such functions can elicit a negative as well as positive experience for each user.ConclusionOlder and younger adults can utilise an eHealth mobile app to complement their rehabilitation and health care. If the technology works well, is tailored to the individual and in-depth personalised guidance and support is provided, it could assist maximisation of hearing aid uptake, promotion of self-management and improving outcomes.

Altered Functional Network in Infants With Profound Bilateral Congenital Sensorineural Hearing Loss: A Graph Theory Analysis

Functional magnetic resonance imaging (fMRI) studies have suggested that there is a functional reorganization of brain areas in patients with sensorineural hearing loss (SNHL). Recently, graph theory analysis has brought a new understanding of the functional connectome and topological features in central neural system diseases. However, little is known about the functional network topology changes in SNHL patients, especially in infants. In this study, 34 infants with profound bilateral congenital SNHL and 28 infants with normal hearing aged 11–36 months were recruited. No difference was found in small-world parameters and network efficiency parameters. Differences in global and nodal topologic organization, hub distribution, and whole-brain functional connectivity were explored using graph theory analysis. Both normal-hearing infants and SNHL infants exhibited small-world topology. Furthermore, the SNHL group showed a decreased nodal degree in the bilateral thalamus. Six hubs in the SNHL group and seven hubs in the normal-hearing group were identified. The left middle temporal gyrus was a hub only in the SNHL group, while the right parahippocampal gyrus and bilateral temporal pole were hubs only in the normal-hearing group. Functional connectivity between auditory regions and motor regions, between auditory regions and default-mode-network (DMN) regions, and within DMN regions was found to be decreased in the SNHL group. These results indicate a functional reorganization of brain functional networks as a result of hearing loss. This study provides evidence that functional reorganization occurs in the early stage of life in infants with profound bilateral congenital SNHL from the perspective of complex networks.

Prevalence of Hearing Loss in Type 2 Diabetes Mellitus and Its Association with Severity of Diabetic Neuropathy

Purpose This study assessed the prevalence of hearing loss (HL) in patients with Type 2 Diabetes (T2DM) and its relationship with the presence and severity of diabetic neuropathy. Methods Patients between the ages of 30 to 60 years (both ages inclusive) with T2DM were recruited and divided into three groups. Group 1 included patients without neuropathy. Group 2 had patients with mild neuropathy. Group 3 had patients with moderate and severe neuropathy. After informed consent hearing threshold was assessed using pure tone audiometry (PTA). Results Of the 200 patients recruited, the prevalence of hearing loss was overall 81%. The prevalence was 66.7% in group 1, 80.9% in group 2 and 87.6% in group 3 (p=0.009). Among patients with moderate to severe neuropathy (group 3) 33.3% had clinically significant hearing loss (p=0.015). Age, gender, presence of neuropathy and severity of neuropathy were associated with increased risk of developing hearing loss. Severity of hearing loss worsened with increase in severity of neuropathy. Conclusions Age, gender and severity of neuropathy were associated with increased risk of developing hearing loss. Screening for hearing loss in patients with moderate to severe diabetic neuropathy using self-report questionnaires can help in timely diagnosis and treatment.

Can Music Training Improve Listening Skills For Children With Hearing Loss?

Hearing aids and cochlear [ko-clear] implants are very useful devices for children with hearing loss. But they do not completely restore hearing. Many children with hearing loss find it difficult to listen in noisy places like the playground. This is important because many social interactions create noise or occur in noisy places. While most people think we listen through our ears, it is the brain that does most of the hard work! We thought that music training might be a good way to improve listening skills. Why? Because music is a fun activity that involves not only sounds, but also sights, movement, memory, and more! This means a lot of activity and learning, which is good for the brain. What did we find? After 12 weeks of music training, children with hearing loss were better at listening, particularly in noisy environments.