Prevalence of Noise Induced Hearing Loss Among the Workers of Metallurgical Factory; A study Conducted at Nishtar Hospital Multan

Objective: To evaluate the prevalence of nose induced hearing loss in the industrial workers and its association with age, gender and duration of exposure. Study design: A cross sectional study. Methodology: Cross sectional study was conducted at ENT department of Nishtar Hospital Multan from July 1st 2018 to June 30th 2019. Age, gender, duration of exposure, overtime workers and presence of NIHL was noted for 316 workers. Three age groups were made i.e. <30 years, 30-40 years and >40 years. Duration of exposure was categorized as <5 years, 5-15 years, and >15 years. Overtime workers were classified as those who worked for >8hours daily. Workers having NIHL were compared in both genders, age groups, exposure duration groups and according to daily duration of work. Number and percentages were calculated. Results were significant if p ?0.05. Results: At the time of study, 67 (21%) had developed noise induced hearing loss. Considering exposure duration of workers to noise, 12% with <5years of exposure; 28.8% with 5-15years of exposure; and 28.7% with >15years of exposure developed NIHL (p=0.001). Frequency of NIHL was 38.4% in overtime workers as compared to 16% among regular workers (p<0.001). Conclusion: The prevalence of NIHL is very high among the workers who are constantly exposed to noise and it rises with the prolongation of total exposure time as well as daily exposure time.