Study in murine model: Is there a relationship between presbycusis and frailty?

Abstract

Age-related hearing loss (ARHL) or Presbycusis is the most frequent sensory deficiency in older adults and is associated with comorbidities, such as falls, cognitive decline, and frailty. Frailty is related to poor health outcomes in old age. Recent research suggested that ARHL may be a potentially modifiable risk factor for frailty, although inconclusive. The use of animal models to study the correlation between ARHL and frailty is important to test future interventions to be translated into clinical practice. The aim of this study was to determine if there is an association between ARHL and frailty in experimental animals based on the human frailty phenotype. This research studied male and female C57Bl/6J mice, at different ages (6, 14, and 22 months). Auditory steady-state responses (ASSR) threshold shifts were measured at different frequencies. To assess frailty status, we were based on the "Valence Score" which consists of measuring: weakness, weight loss, low level of activity, slowness, and little resistance. We found that hearing is significantly lower in older age groups. The mice become frail as they age. The worsening in ASSR threshold shifts with age correlates significantly with an increasing frailty. No significant differences were found between both sexes. Our research is, to our knowledge, the first carried out in experimental animals to establish the association between ARHL and frailty, which would provide a useful tool to evaluate future interventions in mice before translating them into clinical practice.