Presbycusis: Comparison between the Auditory Brainstem Response (ABR) and the Pure Tone Audiometry (PTA) in Presbycusis Patient
Background: Presbycusis is a complex phenomenon resulting from an elevation hearing levels as well as changes in auditory processing. Chronic diseases such as diabetes (D), arterial hypertension (H) may act as an accelerating factor in agerelated degeneration of the auditory system. The most used diagnostic test is PTA, ABR is recorded when the pure tone audiometry cannot be access.
Objective: to compare the relation between ABR and PTA threshold in presbycusis patients and evaluate the influence of diabetes and/or hypertension on the relationship between ABR and PTA threshold.
Material and methods: This is a prospective hospital-based study on the comparison between ABR and PTA of presbycusis patients (≥ 50 years old) composed of 35 females and 21 males. The participants were divided into groups, set as follows group 1 composed of 21 patients, group 2 comprising 12 patients, group 3 made of 14 patients and group 4 composed of 9 patients.
Results: The comparison between the mean threshold difference of ABR and PTA in group I and II was significant at each frequency with the mean difference in decibel was<20 dB at high frequency and>20 dB at 0.5 and 1 kHz in group 2,while in group 2 a mean difference<20 dB at all frequency range. Group III exhibited a significant difference at high frequency only, we found a mean difference<20 dB at 4, 8 and 2-4 kHz and>20 dB at 0.5, 1, and 2 kHz. However, group IV showed no significant difference between ABR and PTA thresholds, the mean threshold difference was>20 dB at each frequency.
Conclusion: it was found that there is a positive relationship between ABR and PTA, threshold, which appear to be insignificant in presbycusis patients with both hypertension and diabetes; this may be probably related to synergic effects of the two chronic illnesses on the cochlea.