Auditory brainstem response test at different stimulus rates in normal-hearing adults living with HIV

Abstract

PURPOSE : The study investigated whether the auditory brainstem response (ABR) at a baseline and at higher repetition rates can detect if neurodegeneration has occurred in adults living with HIV who present with normal behavioral pure-tone thresholds. METHOD : An exploratory research design was used. Forty adults with HIV (80 ears, 57.5% female; M age = 26.3 years, SD = 3.68) and 20 adults without HIV participated. Phase 1 compared ABR absolute and interwave latencies at a baseline rate. Phase 2 examined the effect of HIV status and category of immunodeficiency on ABR absolute Wave V latency and Wave V latency shift at increased stimulus rates. Analysis included a two-way analysis of variance of the interaction between stimulus rate and HIV status and between CD4+ category and rate, and multiple regression analysis. RESULTS : In adults living with HIV, the baseline ABR yielded prolonged Wave III and V absolute latencies and interpeak prolongations in 22.5%. Interaural Wave V latency differences were present in 15% of participants. An additional 15% of ears presented with abnormal Wave V at increased rates. No significant interaction between HIV status and rate in either ear or between CD4+ category and rate was found in either ear (p > .05). Although rate and gender contributed significantly to the prediction of Wave V latency of the rate study (left and right, p < .001), HIV status did not (left and right, p > .05). CONCLUSIONS : Although the interaction of HIV status and CD4+ with rate was not significant, more ears were identified with abnormal results at increased stimulus rates than with the baseline ABR alone. The ABR at increased rates may therefore be a valuable addition for the identification of individuals living with HIV with auditory neural deficiencies.