Correlation between the age-dependent changes in caloric response and in pure tone hearing

Abstract

Previous reports have examined the age-dependent changes of the auditory system or the caloric response, but results have been inconsistent. No study to date has correlated the age-dependent changes in caloric response with those in pure tone hearing in the same subjects. In this study a caloric test and a pure tone audiometry test were performed in 86 subjects (172 ears), age range 24 to 84 years of age, including 12 otoneurologically healthy volunteers (24 ears), and 74 tinnitus patients without subjective hearing loss (148 ears). The maximal slow phase eye velocity (SPEV) of caloric nystagmus response and the mean hearing level at high frequencies were measured and the age-dependent changes in these scores were compared. The following results were obtained. 1) The SPEV of caloric nystagmus, which remained unchanged until markedly advanced age, decreased significantly from 65 years of age in men and from 75 years in women; the change occurring earlier in men than in women. 2) The hearing level at high frequencies decreased abruptly from 50 years of age with a more gradual change from 75 years was significantly lower in men than in women over 65 years of age. 3) There was a weak but significant correlation between the age-dependent changes in SPEV and those in hearing level at high frequencies.