The Complexity of Age-Related Hearing Impairment: Contributing Environmental and Genetic Factors

  title={The Complexity of Age-Related Hearing Impairment: Contributing Environmental and Genetic Factors},
  author={Els Van Eyken and Guy Van Camp and Lut Van Laer},
  journal={Audiology and Neurotology},
  pages={345 - 358}
Age-related hearing impairment (ARHI) is the most common sensory impairment seen in the elderly. It is a complex disorder, with both environmental as well as genetic factors contributing to the impairment. The involvement of several environmental factors has been partially elucidated. A first step towards the identification of the genetic factors has been made, which will result in the identification of susceptibility genes, and will provide possible targets for the future treatment and/or… 

Figures and Tables from this paper

Environmental and genetic factors in age-related hearing impairment

An overview of the current data on ARHI is given, focusing mainly on environmental agents and genetic predisposition in animal models and in humans, to improve the understanding of ARHI.

The Genetic Basis of Hearing Loss: Recent Advances and Future Prospects

Patients with HL of undiagnosed etiology should be evaluated by a clinical geneticist and consider genetic testing as a part of their multidisciplinary evaluation, to establish the genetic cause of HL in prelingual children.

NAD(+) Metabolism in Age-Related Hearing Loss.

The role of NAD(+) metabolism in aging and age-related diseases, including ARHL, is described and a potential strategy for prevention or treatment of ARHL is discussed with a particular interest in NAD(+)-dependent cellular pathways.

A genome-wide association study for age-related hearing impairment in the Saami

A genome-wide association study in the Finnish Saami, a small, ancient, genetically isolated population without evidence of demographic expansion, provides further evidence for the involvement of GRM7 in ARHI.

Genetics of Postlingual Sensorineural Hearing Loss

Main concepts in genetics as related to HL are outlined, implicated genes are identified, and implicated genes' clinical implications are discussed to discuss clinical implications of gene–environment interactions.

Genetics of Hearing Loss

All Mendelian pattern of inheritance have been observed in nonsyndromic HL (NSHL) including autosomal dominant (AD), autosomal recessive (AR), X-linked inheritance (XL) and mitochondrial inheritance (MT); autosome recessive is the main form of NSHL, i.e. 75-85 % of NS HL show AR pattern in affected pedigrees.

The genetics of progressive hearing loss: a link between hearing impairment and dysfunction of mechanosensory hair cells.

This study identified a highly significant single nucleotide polymorphism (SNP) in the gene coding a metabotropic glutamate receptor (GRM7) that is associated with hearing loss in mice and aims to define the function of the genes that are linked to auditory impairment.

Hearing among older adults–an epidemiological study

It seems that most of the subjects reporting hearing difficulty had no measured hearing impairment according to the criteria applied for eligibility for hearing aid fitting in Finland, and this should be taken into account when future hearing healthcare is planned.

Ultrarare heterozygous pathogenic variants of genes causing dominant forms of early-onset deafness underlie severe presbycusis

The findings demonstrate that the genetics of presbycusis is shaped by not only well-studied polygenic risk factors of small effect size revealed by common variants but also, ultrarare variants likely resulting in monogenic forms, thereby paving the way for treatment with emerging inner ear gene therapy.

Pathophysiology of Age-Related Hearing Loss (Peripheral and Central)

This study reviews the literature on the age-related hearing loss and finds that metabolic presbycusis is the mainstay of pres bycusis types, and functional decline of the central auditory system, caused by aging, reduces speech-understanding in noisy background and increase temporal processing deficits in gap-detection measures.



Age-related hearing loss: current research

By defining the molecular basis of normal and impaired auditory function, therapies can be developed to ameliorate the effects of aging in the auditory system, and a summary of current research efforts is presented.

KCNQ4: a gene for age‐related hearing impairment?

SNPs in a candidate susceptibility gene, KCNQ4, were examined in two independent Caucasian populations and several SNPs were positively associated with ARHI: one SNP (SNP18) for the high frequencies and three SNPs (SNp9, SNP12, and SNP18)for the low frequencies, although only a single SNP ( SNP12) resulted in significant p‐values in both populations.

A Novel Z-Score–Based Method to Analyze Candidate Genes for Age-Related Hearing Impairment

The Z-score conversion appears to be a valid method to describe to what extent a subject is affected by ARHI, allowing to compare persons from different age and gender.

Is DFNA5 a susceptibility gene for age-related hearing impairment?

There exists no strong association between DFNA5 and ARHI, and it is concluded that there exist no significant differences in genotypes between good hearing and hearing impaired individuals.

Molecular mechanisms of age-related hearing loss

Genetic influences on susceptibility of the auditory system to aging and environmental factors.

  • H. S. Li
  • Biology, Medicine
    Scandinavian audiology. Supplementum
  • 1992
Auditory susceptibility to aging and environmental factors (noise and toluene) was investigated in two genotypes of mice, CBA/Ca (showing a moderate hearing loss with onset late in life) and C57BL/6J

Age-related hearing loss: the status of Schuknecht’s typology

  • K. Ohlemiller
  • Biology
    Current opinion in otolaryngology & head and neck surgery
  • 2004
Using Schuknecht’s framework as a guide, basic research can now seek to model specific forms of ARHL by combining genetic defects and appropriate environmental conditions.

Characterization of hearing loss in aged type II diabetics

Hearing impairment susceptibility in elderly men and the DFNA18 locus.

The results suggest that genetic variation in the region of DFNA18 may be responsible for hearing loss with age in the general population, the first sample from the generalpopulation that has been used in a genome screening for qualitative hearing loss.

Ahl3, a third locus on mouse chromosome 17 affecting age-related hearing loss.