Diabetes-related changes in auditory brainstem responses.
OBJECTIVE
Determine effects on auditory brainstem response (ABR) of diabetes mellitus (DM) severity.


METHODS
A cross-sectional 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, 50-56, and 57+). DM severity was classified as insulin-dependent (IDDM), non-insulin-dependent (NIDDM), or no DM. Other DM measures included serum glucose, HbA1c, and several DM-related complications. ABR measures included wave I, III, and V latencies; I-III, III-V, and I-V 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. Self-reported 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 I-V interval, and reduced wave V amplitude among Veterans under 50 years. Results were related to several DM complications.
Konrad-Martin
Dawn
D
Veterans Affairs Rehabilitation Research and Development Service, National Center for Rehabilitative Auditory Research, Portland Veterans Affairs Medical Center, Portland, Oregon 97239, USA. dawn.martin@va.gov
Austin
Donald F
DF
Griest
Susan
S
McMillan
Garnett P
GP
McDermott
Daniel
D
Fausti
Stephen
S
D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D048909:Diabetes Complications / Q000503:physiopathology; D003920:Diabetes Mellitus / Q000503:physiopathology*; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology; D016057:Evoked Potentials, Auditory, Brain Stem; D034381:Hearing Loss / Q000150:complications; D006801:Humans; D008875:Middle Aged