Hearing loss and brain disorders: A review of multiple pathologies

Abstract

Several causative factors are associated with hearing loss (HL) and brain disorders. However, there are many unidentified disease modifiers in these conditions. Our study summarised the most common brain disorders associated with HL and highlighted mechanisms of pathologies. We searched the literature for published articles on HL and brain disorders. Alzheimer’s disease/dementia, Parkinson’s disease, cognitive impairment, autism spectrum disorder, ataxia, epilepsy, stroke, and hypoxic-ischaemic encephalopathy majorly co-interact with HL. The estimated incidence rate was 113 per 10,000 person-years. Genetic, epigenetic, early life/neonatal stress, hypoxia, inflammation, nitric oxide infiltration, endoplasmic reticulum stress, and excess glutamate were the distinguished modifiers identified. Various mechanisms like adhesion molecules, transport proteins, hair cell apoptosis, and neurodegeneration have been implicated in these conditions and are serving as potential targets for therapies. To improve the quality of life of patients, these understandings will improve clinical diagnoses and management of HL and brain disorders.

Hearing loss is not associated with risk of Parkinson's disease: A Mendelian randomization study

“…One study in Taiwan comprising 4976 hearing loss elderly people and 19,904 non-hearing-loss elderly people discovered that the cumulative incidence rate of PD in the former group was higher than that in the latter group, and the incidence rate of PD in two groups climbed with age [ 33 ]. The fundamental process may be the activation of inflammation or hypoxia in hair cells after hearing loss, which causes cytokines and an overproduction of reactive oxygen species-both of which are implicated in PD [ 34 ]. On the one hand, α-synuclein is mainly located in the outer hair cells of the inner ear to maintain the physiological function of hearing.…”

(Zu-)Hören mit alterndem Gehirn – eine kognitive Herausforderung

“…Age-related deficits lead to restrictions in communication ability, social isolation and, associated with this, to psychological stress and reduced quality of life. The question of a possible causal relationship between hearing loss and reduced cognitive abilities up to manifest dementia has increasingly become the focus of scientific research in recent years (see comprehensive reviews in e. g. 53 146 166 193 194 195 196 ). The analysis of already published study results is complicated by the great heterogeneity of the collected data, both in terms of audiological and cognitive parameters, as well as in terms of the studied groups, recorded influencing factors, and duration of follow-up.…”

“…B. 53 146 166 193 194 195 196 ). Die Analyse bereits publizierter Studienergebnisse wird durch die große Heterogenität der erhobenen Daten erschwert, sowohl im Hinblick auf die audiologischen und kognitiven Parameter, als auch auf die untersuchten Gruppen, erfassten Einflussfaktoren und Beobachtungsdauer.…”

Leveraging human–mouse studies to advance the genetics of hearing impairment in Africa

“…1 Abnormal development or damage to the hearing system can cause HI. 2 The normal range for audio frequency required for adequate hearing is between 20 and 20,000 Hz.…”