Association of smoking with hearing loss—a hospital based retrospective case–control study

Abstract

Background: Smoking is known to be a risk factor for several lifestyle diseases ranging from chronic obstructive pulmonary disease to devastating conditions like lung carcinoma. Free radical damage and oxidative stress due to the contents of tobacco smoke lead to a decrease in vascularity of the auditory nerve and cochlea and thus lead to hearing loss. Tobacco smoke-induced middle ear mucosal edema and Eustachian tube dysfunction and edema can also contribute to hearing loss. Aim and objective: This study was carried out to find the association between smoking and hearing loss in male patients attending the Otorhinolaryngology OPD of AIIMS Rajkot. Materials and methods: Our study was a retrospective case–control study carried out over a period of 1 year and included 90 participants, amongst which 45 were smokers and 45 were non-smokers. Patient data pertaining to smoking history, along with examination and audiometric evaluation, which was carried out in a soundproof room, was taken. Data analysis was done using appropriate statistical tests. Results: Majority of patients amongst the 2 groups were in the middle age (40–60 years age group) having mild type of sensorineural hearing loss. The p values were not significant. The smokers with a higher smoking index of > 20 had worst audiometric thresholds (p value < 0.05) The p value for the relationship between smoking duration and hearing loss was 0.0169, which was statistically significant, suggesting a strong evidence that smoking duration is significantly associated with hearing loss.