Contributing factors to tinnitus in diabetics
Approximately 30 million people in the U.S. alone have a form of diabetes, a group of diseases that affect your body’s ability to properly use an excess amount of glucose (sugar) in your bloodstream. Of these, an estimated 34.5 million also have some type of hearing loss, which is twice as common in diabetics as in people without the disease. While hearing loss and tinnitus occur independently of one another, in many cases the root cause of one also leads to the other.
Three potential triggers for hearing damage and subjective tinnitus in people with diabetes include the following:
Inadequate blood flow, a known complication of diabetes. When blood sugar increases, it thickens your blood and makes it very difficult to pass through the tiny capillaries of your cochlea (inner ear). This restricted blood flow damages and eventually destroys the fragile stereocilia (hair cells) that conduct sound from your cochlea to your auditory cortex for processing. The more of them you lose, the less you’re able to hear and process external sounds properly.
Exposure to high blood sugar over a long time can damage the eighth cranial nerve, which is responsible for transmitting sound and balance information from your inner ear to the brain.
Even slightly elevated blood sugar over time can interfere with the enzyme known as the ATPase pump, which creates the optimal potassium and sodium concentrations for inner ear fluid. This is also necessary for balance and good hearing.
What is Tinnitus? Signs and Symptoms
Tinnitus is one of the most elusive conditions that health care professionals face. It is an auditory perception not directly produced externally.
It is commonly described as a hissing, roaring, ringing or whooshing sound in one or both ears, called tinnitus aurium, or in the head, called tinnitus cranii.
The sound ranges from high to low pitch and can be a single tone, multi-tonal, or noise-like, having no tonal quality. Tinnitus may be constant, pulsing or intermittent. It may begin suddenly or progress gradually.
Tinnitus can be broadly classified into two categories: objective and subjective.
This form is audible to an observer either with a stethoscope or simply by listening in close proximity to the ear. Objective tinnitus accounts for less than 5 percent of overall tinnitus cases and is often associated with vascular or muscular disorders. The tinnitus is frequently described as pulsatile, or synchronous with the patient’s heartbeat. In many instances, the cause of objective tinnitus can be determined and treatment, either medical or surgical, may be prescribed.
This form is audible only to the patient and is much more common, accounting for 95 percent of tinnitus cases. Subjective tinnitus is a symptom that is associated with practically every known ear disorder and is reported to be present in over 80 percent of individuals with sensorineural hearing loss, which is caused by nerve and/or hair cell damage.
Because tinnitus, like pain, is subjective, two individuals may demonstrate identical tinnitus loudness and pitch matches yet be affected in significantly different ways. The severity of the tinnitus is largely a function of the individual’s reaction to the condition. That said, many tinnitus sufferers:
- Have difficulty sleeping or concentrating
- Feel depressed or anxious
- Report additional problems at work or at home that may contribute to the distress caused by tinnitus
- Describe a correlation of tinnitus perception with stress
- It is often difficult to determine whether a patient’s emotional state pre-existed, or is a result of the tinnitus.
Although the exact mechanism underlying tinnitus is unknown, it is likely that there are many related factors. Tinnitus usually, but not always, has to do with an abnormality of the hearing or neural system.
There are a number of causes linked with tinnitus including:
- Disorders in the outer ear, such as ear wax, a hair touching the eardrum, a foreign body or a perforated eardrum
- Disorders in the middle ear, such as negative pressure from eustachian tube dysfunction, fluid, infection, otosclerosis, allergies or benign tumors
- Disorders in the inner ear, such as sensorineural hearing loss due to noise exposure, aging, inner ear infection or Meniere’s disease often accompanied by hearing loss and dizziness
- Tinnitus also can temporarily result from certain medications, such as:
- Anti-inflammatories such as aspirin, ibuprofen, nonsteroidal anti-inflammatories and quinine
- Certain antibiotics and chemotherapeutic agents
Other causes include:
Systemic disorders such as high or low blood pressure, anemia, diabetes, thyroid dysfunction, glucose metabolism abnormalities, vascular disorders, growth on jugular vein, acoustic tumors and head or neck aneurysms
Non-auditory disorders such as trauma to the head or neck, temporomandibular (jaw joint) disorders and neck misalignment
Current research suggests that even though tinnitus may initially be caused by an injury to the ear, ultimately an auditory pattern is established in the brain. Therefore, many treatment approaches are directed at the brain, not the ear.
Although the majority of tinnitus sufferers also have hearing loss, the presence of tinnitus does not indicate that one is losing hearing.