Study links smokers to increased risk of hearing loss

Used cigarettes in an ash tray

Study links smokers to increased risk of hearing loss

While there are hereditary factors that can increase your risk of hearing loss, several external factors play a role as well. According to a review in the journal Environmental Health Perspectives, ototoxic drugs, viral and bacterial infections, aging and exposure to noise are the most common environmental factors that lead to hearing loss. Cigarettes are among those ototoxic drugs and new research confirms that smoking increases the risk of hearing loss.

Smoking increases hearing loss risk
A recent study in Nicotine & Tobacco Research, published by Oxford University Press, concluded that individuals who smoke have an increased risk of hearing loss. Researchers studied more than 50,000 Japanese employees over an eight-year period, all of whom had no hearing loss at the start of the study. At present, this is the largest study to date to analyze the relationship between tobacco and hearing loss risk.

Study participants had three different relationships with smoking, Reuters reported:

  • 19,000 were current smokers.
  • 9,800 were former smokers.
  • 21,000 had never smoked.

Of the total participants, 3,532 were diagnosed with high-frequency hearing loss and 1,575 developed low-frequency hearing loss, study authors concluded. For eight years, participants took part in annual questionnaires about health and lifestyle as well as regular checkups that included audio testing performed by a technician. Other factors such as noise were taken into consideration and even still, researchers found a 1.2 to 1.6 heightened risk of loss of hearing for current smokers. This was compared to those who had never smoked.

Frequency and increased risk
For every single cigarette a person smokes in a day, their risk of hearing loss increases, Reuters reported. The difference between just 10 cigarettes and 11 cigarettes per day was quite telling, as the risk of hearing loss increased significantly.

Smoking was found to cause both high-frequency hearing loss, when people have trouble deciphering speech in loud and busy settings, and low-frequency hearing loss, when deep voices are challenging to make out. When compared to their non-smoking counterparts, participants that had a current smoking habit were 60 percent more likely to be diagnosed with high-frequency hearing loss and 20 percent more likely to experience low-frequency hearing loss.

Another key finding from the study was that once an individual decided to quit smoking, the risk of hearing loss drops quite quickly, as lead study author Huanhuan Hu of the Department of Epidemiology and Prevention at the National Center for Global Health and Medicine in Tokyo explained.

"Quitting smoking virtually eliminates the excess risk of hearing loss, even among quitters with short duration of cessation," Hu said. "Because the risk of hearing loss increases with the number of cigarettes smoked per day, if quitting is impossible people should still smoke as little as possible."

The researchers did cite various limitations to the study. According to Reuters, it was up to the participants to report on their smoking habits so the issue of accuracy does come up. Since it was not a controlled experiment intended to determine how hearing loss is caused, researchers are unsure of how cigarettes cause damage. However, exposure to nicotine may cause harm to the ears, noted Hu.

Regardless of limitations, the connection between smoking and hearing loss is clear and, as a result, individuals hoping to decrease their risk may want to consider cutting back on smoking.

Cigarettes are among those ototoxic drugs and new research confirms that smoking increases the risk of hearing loss.