In focus Tinnitus
“Not enough attention is paid to tinnitus” Tinnitus can dramatically lower the quality of life. Effective treatments are lacking, but new research which shows that, in some specific cases, tinnitus can be hereditary can hopefully lead to new drugs in the future. Text: Maja Lundbäck Photo: Annika af Klercker
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ODAY, EVERY SIXTH Swede experiences tinnitus, the perception of sound that do not physically exist. Tones are the most commonly perceived sound, but buzzing, peeping, humming, swishing, droning, whooshing, whistling, or beats that follows the heart rhythms can also be heard. For most people the symptoms are mild, but for about ten percent of those affected, tinnitus is extremely troublesome. “Not being able to get away from tinnitus often results in clinically significant stress and anxiety. Some people have problems sleeping, with their social life, and difficulties working; the risk of sick leave and disability pension increases,” comments Christopher Cederroth, a researcher at the Department of Physiology and Pharmacology at the Karolinska Institutet. Every second person with tinnitus also suffers from sound hypersensitivity, which in a mild form makes it more difficult to be present in noisy surroundings or go to a restaurant; in the worst cases each small sound is a nightmare.
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Medical Science–2018
TINNITUS IS STILL NOT classified as a disease, but as a symptom of other diseases. “This is most probably the reason why tinnitus has not received sufficient attention as an important health issue. But I believe that certain forms can be considered as diseases,” says Christopher Cederroth. Many people have experienced “ringing” in their ears after a loud concert. Often the problem
has disappeared the next morning. But according to Christopher Cederroth, it isn’t that simple. “This ringing is a sign that a damage has occurred, and repeated exposure to noise can result in permanent tinnitus. This even applies to music that you listen to at a moderate volume, because it’s also a question of how often you listen,“ he explains. THE CURRENT THEORY among researchers in the field is that tinnitus occurs when the sensitive nerve cells in the inner ear, generally those that capture the highest frequencies, are damaged. The brain, which is used to receive this sensory input, tries to compensate for the loss of these signals. This results in a type of overactivity in the nerve cells in the brain. Likewise as it is possible to experience sensations from an amputated part of the body, the sensation of sound can be experienced at the same frequency than that at which damage has occurred. “Animal studies have shown an increased activity in the brain’s auditory centre, but the emotional and cognitive areas of the brain can also contribute to reinforcing tinnitus. If we feel stressed, anxious or think about tinnitus, the activity in the brain’s auditory centre increases and the burden accompanying tinnitus is exacerbated,” explains Christopher Cederroth. IN SWEDEN, cognitive behavioural therapy, CBT, is recommended, which can make it easier for people to manage their symptoms; however, psychoth-
Effective treatments are available, but more are needed Treatments with proven effect: CBT: Psychotherapy that can make the symptoms easier to manage. Notch music therapy: An app that filters out sounds that are at the same frequency as the tinnitus tone. Hearing aids: For patients with hearing loss. Cochlea implant: The auditory nerve in the inner ear is stimulated using weak electrical impulses; highly effective for people with hearing loss. Promising treatment: Vagus nerve stimulation: An electrode implanted in the body stimulates a nerve at the same time as the person hears a certain sound. Only a handful of small studies on people. There is also a number of alternative treatments that lack scientifically-evidenced effect. Source: Christopher Cederroth