Noise-induced hearing loss among traffic policemen in the city of Colombo, Sri Lanka

Abstract

Noise-induced hearing loss (NIHL) is a high frequency sensory-neural hearing loss and exposure to traffic noise by traffic policemen makes them susceptible to develop NIHL. The objective of this study was to determine the prevalence and correlates of NIHL among traffic policemen in the city of Colombo, Sri Lanka. A cross sectional study was carried out using 350 traffic policemen who are working in the city at least six months of duration. Pure-tone audiometry test and interviewer-administered questionnaire were used to assess hearing and correlates of NIHL, respectively. The chi-square test and logistic regression was used to analyze the relationship between risk factors and NIHL. 287 policemen attended pure-tone audiometry test to check their hearing. Of 287 subjects, the prevalence of NIHL was found in 118 policemen (41%; 95% CI: 36%-47%). Of those with any type of NIHL, 33% (39/118) had major NIHL while 67% (79/118) had minor NIHL. In bivariate analysis 23 variables showed statistically significant association with mild and major NIHL. Multivariate logistic regression modelling found statistically significant association between “duration of employment as a policeman” and any type of NIHL (OR = 1.007; 95% CI = 1.005-1.009), adjusted for 23 variables including age. The prevalence of NIHL among traffic policemen in the city was high. Of those with any type of NIHL, one-third had major NIHL. Traffic policemen should undergo periodic hearing assessment. The police department should explore the feasibility of reducing the number of hours per day spent on the road by traffic policemen.