Cigarette smoking and hearing loss

Fri, May 25. 2012

by: Shannon Durrant BSc., BSA Certified Audiometrist & Treasurer of the St Vincent and the Grenadines Medical Association.

One of the most dynamic functions of the human body is the ability to hear and interpret sound from our environment. To determine its direction and source can alert you to danger or secure you to safety.{{more}}

The hearing process is extremely complex and so is the hearing mechanism. Within our skull, there is a complex collection of hearing parts, beginning from the Pinna attached outside of our heads, a short ear canal leading to the ear drum, then unto three of the smallest bones in the human body and a snail-shaped organ called the cochlea, which is a fluid filled organ lined with millions of hair-like projections waving in the cochlear fluid; these are responsible for sending sound messages to the brain via the Auditory nerve.

Research presented at the 2011 Annual Convention of the American Speech-Language-Hearing Association concluded that regardless of gender, smokers are at a greater risk for inner ear-cochlea damage than non smokers.

Harvard researchers analyzed smoking behaviour of 90,961 families between 2007 and 2008 and similarly concluded a higher incidence of recurrent ear infections than in the households that do not use tobacco products.

Other studies by author Dr Michael Weitzman, from New York University’s School of Medicine, reveal that non-smokers living with a smoker were found to be 1.94 times more likely to suffer from hearing problems, as well as doubling a teenager’s risk of hearing loss significantly enough to impair a teen’s ability to understand speech, and has also been linked to poor academic performance and disruptive behaviour in school.

A recent published report on AudiologyOnline from Western Michigan University, authored by Dr Bharti Katbamna, indicates a strong link between smoking and hearing loss, where the risk of becoming hearing-impaired often increases with the number of cigarettes smoked.

Unfortunately the negative effects of smoking do not stop within the inner ear, but actually continue on into the brain. Once sound is transmitted via the auditory nerves, the next process of “hearing” a sound requires our brain to first identify the source of the sound, interpret the sound and call on your brain’s memory to understand the sound being heard. And according to Dr Katbamna’s report, findings from various studies “suggest that chronic nicotine use impairs cognitive auditory processing”. In other words smoking can negatively impair the brain’s ability to “hear” and interpret sounds.

Nicotine and carbon monoxide that result from smoking tighten your blood vessels, including the ones in your ears. This restricts the blood flow and thus the life-giving oxygen in the inner ear. The tiny hair cells in the cochlea that are responsible for translating sound vibrations into electrical impulses for the brain, can thus face damage due to this type of asphyxiation.

Nicotine can affect the chemical messengers (or neurotransmitters) in the auditory (hearing) nerve and thus would not be able to accurately tell the brain what kind of sound is really being processed.

Adolescent smoking has shown mechanisms within the auditory nerve that are not fully developed until late adolescence; thus the hearing nerve pathways are particularly susceptible to damage.

Cigarette smoking and other tobacco use, when coupled with other environments, create a generation of people who lose the ability to hear earlier in life, according to long-tested, proven documentation.

So, if you are not a smoker, don’t start. And, regardless of age, if you are a smoker, by all means, consider quitting.