Does Smoking Cause Hearing Loss?
It is well known that cigarette smoke causes many health issues including heart disease, cancer, and lung disease. But did you know that it can also cause hearing loss, too?
Almost 14 per cent of the Australian population smoke cigarettes every day. Just think about how many other Australians are exposed to secondhand smoke by being around smokers. This is particularly worrying as many children are exposed to secondhand smoke.
Let’s take a look at how hearing works, what types of hearing loss there are, and how cigarette smoke affects the hearing of both smokers and those close to them.
How does smoking affect the hearing?
Different studies have suggested that smoking has a range of adverse effects on hearing. Culprits include the Eustachian tube that connects the middle ear to the back of the throat, the impact smoking has on your blood pressure, as well as the central nervous system.
To better understand how smoking increases the risk of suffering from hearing loss so dramatically, we need to take a step back and look at how hearing works, and how cigarette smoke affects the different parts of your hearing.
How does your hearing work?
The structure of the human ear can be broadly broken down into three main parts. These three parts include the outer ear, the middle ear, and the inner ear.
- The outer ear: The outer ear includes the pinna (external ear) and ear canal.
- The middle ear: The middle ear includes the eardrum, Eustachian tube (a tube linking the middle ear to the back of the nose and throat), and three small bones (malleus, incus, and stapes – also called the ossicles).
- The inner ear: The inner ear includes the hearing organ (the cochlea) and balance organ.
These three parts must all be in good function and work together for normal hearing to occur. In normal hearing, sound waves in the air are collected by the pinna and sent to the eardrum through the ear canal. The waves cause the eardrum to move which causes the ossicles to move.
The ossicles push on the cochlea and the fluid in the cochlea begins to move. This causes the hair cells in the cochlea to bend, creating electrical impulses which are sent to the brain via the hearing nerve and sound is heard.
A problem in any of these parts can result in hearing loss. Cigarette smoke can negatively affect the function of the middle and inner ears, and cause different types of hearing loss.
Types of Hearing Loss
Exposure to cigarette smoke either directly, or indirectly – what we call second-hand smoking, can cause conductive or sensorineural hearing loss.
Problems in the outer ear or middle ear affect how sound is sent to the cochlea, while problems in the inner ear affect how sound is sent beyond the cochlea. The type of hearing loss depends on which part of the ear the issue is in, the outer ear, the middle ear, or the inner ear.
There are three types of hearing loss:
- Conductive hearing loss: Which occurs due to damage to the outer or middle ear. For example, an ear infection in the middle ear.
- Sensorineural hearing loss: This occurs when there is damage to the inner ear. For example, hair cell damage due to substances that are toxic to the ears.
- Mixed hearing loss: This occurs when there is damage to either the outer or middle ear and the inner ear.
Click here to learn more about the things you can do today to protect your hearing.
How does cigarette smoke affect the middle ear?
Cigarettes contain many harmful chemicals. Two of these chemicals which cause hearing damage include nicotine and carbon monoxide. These chemicals affect structures in the middle ear and can cause conductive hearing loss.
The Eustachian tube
The Eustachian tube is a structure in the middle ear and it is a tube connecting the middle ear to the back of the nose and throat. It is responsible for aerating the middle ear, equalising pressure, and draining the middle ear space from any fluid. The Eustachian tube and middle ears are lined with delicate cells.
Chemicals present in cigarette smoke damages these cells and affect the proper function of the Eustachian tube. This means that the Eustachian tube cannot properly clear and a blockage could occur. The cells also have an allergic reaction to the chemicals present in the smoke and the lining becomes irritated.
Smoke is also known to suppress the immune response of the body. In this way, there is a higher chance for bacteria to grow in the middle ear and cause an infection. When fluid is present in the middle ear, this can affect hearing.
How does cigarette smoke affect the inner ear?
As mentioned above, nicotine and carbon monoxide, which are found in cigarette smoke, can cause hearing damage. This occurs as the harmful chemicals can impact inner ear structures and cause sensorineural hearing loss.
The cochlea in the inner ear houses thousands of fine little hair cells which are vital to hearing. The health of these hair cells depends on good blood flow to the cells. These chemicals present in cigarette smoke reduce the amount of oxygen present in the blood vessels in the cochlea as well as constrict the blood vessels in the cochlea.
Without this supply of oxygen, the hair cells become damaged. The hair cells cannot create electrical impulses, affecting hearing.
The Auditory Nerve
The hearing nerve (auditory nerve) in the inner ear is responsible for transferring information (electrical impulses) from the cochlea to the brain where sound is heard. To send this information, the hearing nerve uses messengers (neurotransmitters).
The chemicals in cigarette smoke negatively impact how the ‘messengers’ function. This means that the hearing nerve cannot effectively send the electrical impulses to the brain, affecting hearing.
Hearing Loss – Yet Another Reason To Quit Smoking
Damage to the hair cells in the inner ear cannot be reversed and so hearing loss due to hair cell damage is permanent. It is important to reduce exposure to cigarette smoke – even second hand, to reduce the risk of further damage to the hearing.
If you fear that your habit has already caused damage to your hearing, call your local audiologist today for a hearing assessment.
Second Hand Smoke Also Affects The Hearing
As we’ve mentioned before: People who smoke are not the only ones in danger. Being exposed to second-hand cigarette smoke also increases the risk of hearing loss. Children or partners of smokers inhale smoke indirectly by breathing in not only smoke exhaled by smokers but also smoke from a lit cigarette.
People may second-hand smoke without even realising it. The impacts of second-hand smoking on a person’s health, including ear and hearing health, are just as dramatic as the impacts of first-hand smoking. Second-hand smoke can damage both the middle and inner ears.
It’s Time to Take Action
The connection between hearing loss and smoking might not get enough attention in the media, but we believe it is another strong reason to take the next step and quit smoking! Hearing loss may not be reversible, but it’s never too late to avoid further damage to your hearing health and that of those around you.
Contact Attune Hearing today, to schedule an appointment with one of our friendly audiologists and get your hearing tested!