Comparison of auditory brainstem response in HIV-1 exposed and unexposed newborns and correlation with the maternal viral load and CD4R cell counts

Objective: The effects of maternal HIV infection and antiretroviral therapy on hearing of HIV-exposednewborns in sub-Saharan Africa have not been investigated.Wedetermined the prevalence of sensorineural hearing loss among HIV-exposed newborns and the association between the hearing threshold and maternal and newborn parameters. Design: A cohort audiometric study of newborns between October 2012 and April 2013. Settings: A secondary and tertiary hospital-based study. Participants: Consecutive 126 HIV-exposed and 121 HIV-unexposed newborns. Intervention: Hearing screening of the newborns was done with Auditory Brainstem Response and compared with maternal HAART, CD4⁺ cell counts, RNA viral loads and newborn CD4⁺ cell count percentage. Main outcome measure: Hearing threshold levels of both groups were measured and analysed. Results: Around 11.1% of HIV-exposed and 6.6% of unexposed newborns had hearing impairment (P=0.2214). About 6.4% of HIV-exposed and 2.5% HIV-unexposed newborns had hearing threshold of more than 20 dBHL (P=0.1578). There was no significant association between the hearing thresholds of HIV-exposed newborns and maternal CD4 cell counts (P=0.059) but there was with maternal viral load (P=0.034). There was significant difference between the hearing thresholds of HIVexposed newborns with CD4⁺% of 25 or less and more than 25. This study showed significant difference in the hearing of the 119 HAART-exposed newborns and seven unexposed newborns [P=0.002; risk ratio, 0.13 (0.05-0.32)]. Conclusion: There was a trend towards more hearing loss in HIV-exposed newborns. However, hearing thresholds increase with increasing mothers' viral load. The background information supports the need for further studies on the role of in-utero exposure to HIV and HAART in newborn hearing loss.