Abstract
Objectives/Hypothesis:
Determine effects on auditory brainstem response (ABR) of diabetes mellitus (DM) severity.
Study Design:
A crossโsectional study investigating DM severity and ABR in military Veteran subjects with (166) and without (138) DM and with no more than moderate hearing loss.
Methods:
Subjects were classified by three age tertiles (<50, 50โ56, and 57+). DM severity was classified as insulinโdependent (IDDM), nonโinsulinโdependent (NIDDM), or no DM. Other DM measures included serum glucose, HbA1c, and several DMโrelated complications. ABR measures included wave I, III, and V latencies; IโIII, IIIโV, and IโV latency intervals; and wave V amplitude; for each ear at three repetition rates (11, 51, and 71 clicks/second), and both polarities. Outcomes were stratified by age tertile and adjusted for pure tone threshold at 3 kHz. Repeated measures multivariate analysis of covariance modeled the ABR response at each repetition rate for DM severity (main effect) and hearing at 3 kHz (covariate). Modeled contrasts between ABR variables in subjects with and without DM were examined.
Results:
Significant differences existed between no DM and IDDM groups in the younger tertile only. Adjusting for threshold at 3 kHz had minimal effect. Selfโreported noise exposure was not related to ABR differences, but HbA1c and poor circulation were.
Conclusions:
IDDM is associated with an increased wave V latency, wave IโV interval, and reduced wave V amplitude among Veterans under 50 years. Results were related to several DM complications. Laryngoscope, 2010