Abstract
Occupational noise induced hearing loss (occupational NIHL) is one of the leading causes of permanent hearing impairments not only in developing countries since developed countries such as the US also have a large number of employees who are at risk of occupational NIHL. A number of epidemiological studies have found a positive association between smoking and hearing loss while others show a negative association. Furthermore, in some other studies, no relationship between smoking and hearing loss was found, presenting conflicting evidence of this relationship. This study aimed to exemine the relationship between the exposure which in this case is smoking and the outcome which is occupational NIHL. The study was conducted at the Royal Swaziland Sugar Corporation (RSSC), located in the north-eastern Lowveld of the Kingdom of Eswatini. The goal was to add to the existing knowledge while creating a foundation for further studies in understanding the risk factors of hearing loss which will enable authorities to plan and implement interventions accordingly. The study was done among permanent, contract and seasonal employees at RSSC. Secondary data was collected from occupational health medical records, a total of 1440 data extraction forms were completed, of which 350 were cases and 1090 were controls. The data was then analysed by running frequencies and descriptive statistics. Frequency distributions tables were computed, means, standard deviations and standard errors were used to compute central tendency and dispersion of the data, then logistic regression was used to compute measures of association and confidence intervals. Results of the study have confirmed that smokers, ex-smokers, those with history of ear infection and those exposed to occupational noise are more likely to be diagnosed with NIHL.
M.A. (Public Health)