LXXXIII Biochemical Changes in the Inner Ear Induced by Insulin, in Relation to the Cochlear Microphonics

Metabolic disorders prevalence in sudden deafness

“…The mechanism by which hyperglycemia leads to sudden deafness is not well understood, but we can presume based on in vivo experimental studies that fluctuations in serum glucose lead to changes in serum osmolarity that interfere with outer hair cell motility and function, impairing cochlear microphonics 2,19. According to Lisowska et al, changes in cochlear micromechanics and in the retrocochlear auditory pathway are present as subclinical hearing impairment in diabetic patients 20.…”

“…Although many etiologies have been proposed for this disorder, the etiology can be identified in only 10 to 15% of cases 1. The inner ear can be directly affected by variations in serum insulin as well as by oscillations in plasma glucose levels 2. A health survey in the USA that employed a cross‐sectional analysis of nationally representative data showed that hearing impairment was more prevalent among adults with diabetes than among those without 3.…”

Prevalência das alterações metabólicas em pacientes portadores de queixas vestibulares

“…O autor observou a relação entre surdez sensorioneural e diabetes e estabeleceu o vínculo entre a deficiência auditiva e a hiperglicemia. No ano de 1960 a glicose foi finalmente reconhecida como um dos principais elementos na manutenção da boa atividade funcional da orelha interna 9 . A partir de então, vários autores documentaram as alterações vestíbulo-cocleares secundárias ao diabetes mellitus e à hiperinsulinemia 3,[10][11][12][13] .…”

Auditory Evaluation in Patients with Type 1 Diabetes

“…Other specific, but less frequent, types include genetic defects of beta cell function (MODY, or maturity-onset diabetes of the young, and MIDD, or maternally inherited diabetes and deafness), genetic defects of insulin action, diseases of the exocrine pancreas, endocrinopathies, drug-or chemical-induced dia-betes, infections, immune-mediated diabetes, other genetic syndromes (Down syndrome, Klinefelter's syndrome, Turner's syndrome, Wolfram syndrome, Friedreich's ataxia, Huntington's chorea, Lawrence-Moon-Biedl syndrome, and myotonic dystrophy, among others), 1,3-6 and gestational diabetes. 21 This condition can bring about endolymph retention, hydrops, and auditory alterations. The most common mutation occurs at position 3243 in the tRNA leucine gene.…”