According to a study, researchers determined that prospective association of smoking status, smoking intensity, and smoking cessation with the risk of hearing the loss in a large Japanese cohort. Smoking is associated with increased risk of hearing loss, according to a study of over 50,000 participants over eight years. The study was published in Nicotine & Tobacco Research.

Researchers analyzed data from annual health checkups, which included audio testing performed by a technician and a health-related lifestyle questionnaire completed by each participant. They examined the effects of smoking status, the number of cigarettes smoked per day, and the duration of smoking cessation on the extent of hearing loss.

Even after adjusting for factors including occupational noise exposure, researchers noted a 1.2 to 1.6 increased risk of hearing loss among current smokers compared with never smokers. While the association between smoking and high-frequency hearing loss was stronger than that of low-frequency hearing loss, the risk of both high- and low-frequency hearing loss increased with cigarette consumption.

The increased risk of hearing loss decreased within five years after quitting smoking. "With a large sample size, long follow-up period, and objective assessment of hearing loss, our study provides strong evidence that smoking is an independent risk factor of hearing loss," said the study's lead author Dr. Huanhuan Hu of Japan's National Center for Global Health and Medicine.

"These results provide strong evidence to support that smoking is a causal factor for hearing loss and emphasize the need for tobacco control to prevent or delay the development of hearing loss." Smoking is associated with increased risk of hearing loss, especially at the high frequency, in a dose-response manner. The excess risk of hearing loss associated with smoking disappears in a relatively short period after quitting.

The prospective association between smoking and hearing loss has not been well studied. To the best of our knowledge, the study is the largest to date investigating the association between smoking and incident hearing loss. Our results indicate that smoking is associated with increased risk of hearing the loss in a dose-response manner.

Quitting smoking virtually eliminates the excess risk of hearing loss, even among quitters with short duration of cessation.  These results suggest that smoking may be a causal factor for hearing loss, although further research would be required to confirm this. If so, this would emphasize the need for tobacco control to prevent or delay the development of hearing loss.