Characteristics of Auditory Brainstem Response in Night-shift Health Workers

Background: With technological advancement and economic competitiveness there is an exponential rise in the number of shift workers. Worldwide, healthcare workers constitute the single largest proportion of workers who work on shift duty in order to provide round-the-clock healthcare services to patients. Various studies have demonstrated an association between circadian cycle disturbance due to shift work and adverse health impacts. Purpose: The purpose of the study was to investigate the impact of night shift work on the brainstem-evoked auditory potentials in nursing interns who had been assigned to their first night shift after working day shifts. Methods: A longitudinal, self-case-control study was designed with a sample of 67 nursing interns. Brainstem evoked response audiometry (BERA) had been done after completion of their first posting in Day-shift and then after completion of Night-shift. The paired t-test was used for data analysis. Results: The findings of the study showed significant changes in latencies of wave II ( p < .0001), wave IV ( p < .0001), wave V ( p = .012 & .30), interpeak latency III-V ( p = .009 & .003) and V/I ratio ( p < .0001) for both ears. Conclusions: BERA is an objective non-invasive test to evaluate hearing ability by measuring increased latency and interaural latency difference. After night shift, there were significant changes in auditory acuity which was highly suggestive of delayed transmission in auditory pathway. Hearing impairment has a cascading effect on cognition which may affect night-shift workers’ daily activities and may lead to medical error and risk to patient safety.