Noise Induced Hearing Loss in Autorickshaw Drivers in Bangalore: A Cross Sectional Study

Abstract

To find prevalence of noise induced hearing loss (NIHL) among auto drivers in central Bangalore using a structured questionnaire and audiometric evaluation. To establish a relation between age and duration of work to the presence of noise induced hearing loss among the autorickshaw drivers. To assess the validity of the questionnaire as a screening tool.A cross sectional study conducted in VV Puram, Bangalore from April-August 2019. 100 autorickshaw drivers were subjected to Pure tone audiometry (PTA) evaluation and were asked to answer a self-structured questionnaire comprising of 9 questions. Each question was scored from 0 to 3, making 27 the maximum score a person could obtain. Based on the score they were categorised as mild (6-10), moderate (10-20) and severe ([ 20) hearing loss. Any dip found in the bone conduction in the audiometry at higher frequencies was labelled as presence of NIHL. Age and duration of working hours were noted in order to establish the relation of the two with the presence of noise induced hearing loss.The prevalence of NIHL among the study samples was found to be 40% based on the questionnaire and audiometry test combined. The questionnaire showed a sensitivity of 80% reflecting that it is an efficient tool for screening NIHL among the auto drivers. Prevelance of NIHL was found to be higher among older and study groups with longer working hours. Though majority of the auto drivers did not complain of a hearing loss, a structured questionnaire combined with a pure tone audiometric evaluation helped in identification of early changes of NIHL.