Tinnitus, commonly described as a ringing in the ears, may affect about 750 million people around the world, according to new research based on about 50 years of data.
The study, published this week in the research journal JAMA Neurology, suggests tinnitus is perceived as a major problem by more than 120 million people, most of whom are 65 or older.
Researchers estimate about 14% of adults experience tinnitus, and 2% experience a severe form of it. The prevalence also appears to increase with age: Tinnitus is reported in 10% of adults ages 18 to 44, 14% of adults ages 45 to 64, and 24% of those 65 and older.
The findings align with earlier estimates. The American Tinnitus Association estimates nearly 15% of people, or more than 50 million Americans, experience tinnitus. The National Institute on Deafness and Other Communication Disorders says about 10% of U.S. adults, or nearly 25 million people, have experienced tinnitus lasting at least five minutes in the past year.
"This study suggests that the global burden of tinnitus is large, similar to migraine and pain, and the lack of effective treatment options justifies a major investment in research in this area," researchers wrote.
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What is tinnitus?
While tinnitus is commonly known as a ringing sound in the ears, it can take many other forms, including buzzing, hissing, whistling, swooshing and clicking noises, according to the American Tinnitus Association (ATA). In rare cases, it can sound like music.
The sounds can be soft or loud, high- or low-pitched, and can occur in either one or both ears, according to the National Institute on Deafness and Other Communication Disorders (NIDCD).
The condition can either be temporary or chronic, the ATA said. It's not a disease in itself but is a symptom of other underlying health conditions, according to the association.
What causes tinnitus?
In most cases, tinnitus is a reaction in the brain to damage in the ear or auditory system, according to the ATA. However, the association says, tinnitus can also be a symptom of roughly 200 health problems, including hearing loss, obstructions in the middle ear, and head and neck trauma.
Even something as simple as a piece of earwax blocking the ear canal can cause tinnitus, the NIDCD said. The condition may also be the first sign of hearing loss in older adults or can be a side effect of more than 200 different medications.
Still, some people can develop tinnitus for no obvious reason, the institute said.
"Scientists still haven’t agreed upon what happens in the brain to create the illusion of sound when there is none," the institute said.
Effects of tinnitus
Tinnitus usually isn't a sign of a serious health problem, according to the NIDCD. But if it's loud and persistent, it can cause memory and concentration problems, fatigue, anxiety and depression.
"For some, tinnitus can be a source of real mental and emotional anguish," the institute said.
The ATA also said chronic tinnitus can be a debilitating condition that can interfere with a person's ability to work and socialize.
Who is most at risk?
People at higher risk for tinnitus include older people, active military personnel or veterans, people who work in loud environments, and musicians, according to the ATA.
Military personnel can develop tinnitus when exposed to bomb blasts, and tinnitus is among the most common service-related disabilities for veterans returning from Iraq and Afghanistan, according to the NIDCD.
Is there a cure for tinnitus?
There is "no scientifically validated cure" for most forms of tinnitus, the ATA said. But treatment options can reduce the effects and help people live more comfortably.
The NIDCD recommends going to a primary care doctor to check if anything like ear wax is blocking the ear canal.
If a primary care doctor cannot find the condition that may be causing tinnitus, the physician may refer a patient to a otolaryngologist who specializes in the ear, nose and throat.
Treatments that may help tinnitus include hearing aids, counseling and wearable sound generators, the NIDCD said. Limiting exposure to loud noise also can help prevent tinnitus from worsening.
This article originally appeared on USA TODAY: Study: How many people have Tinnitus? What causes ringing in ears?