Hearing aids appear to improve balance in older adults with hearing loss, say researchers at Washington University School of Medicine in St. Louis. According to their study, published in the October 2014 online issue of The Laryngoscope, the research team found that patients with hearing aids in both ears performed better on standard balance tests when their hearing aids were turned on, as compared with when they were off.
The study was relatively small, reportedly involving 14 people ages 65 to 91, but demonstrated that sound information, separate from the balance system of the inner ear, contributes to maintaining the body’s stability. The study lends support to the idea that improving hearing through hearing aids or cochlear implants may help reduce the risk of falls in older people.
“We don’t think it’s just that wearing hearing aids makes the person more alert,” said senior author Timothy E. Hullar, MD, professor of otolaryngology at the School of Medicine. “The participants appeared to be using the sound information coming through their hearing aids as auditory reference points or landmarks to help maintain balance. It’s a bit like using your eyes to tell where you are in space. If we turn out the lights, people sway a little bit—more than they would if they could see. This study suggests that opening your ears also gives you information about balance.”
According to the announcement from Washington University, all participants served as their own controls, performing the balance tests with and without their hearing aids turned on. Since the researchers were interested in examining the effect of hearing, all tests were conducted in the presence of a sound source producing white noise, similar to the sound of radio static.
In one test, subjects’ eyes were covered as they stood with their feet together on a thick foam pad. In a second, more difficult task, patients stood on the floor with one foot in front of the other, heel to toe, also with no visual cues for balance. Patients were timed to see how long they could stand in these positions without moving their arms or feet, or requiring the aid of another person to maintain balance.
Several of the participants could maintain stability on the foam pad for at least 30 seconds (which is the considered normal), whether their hearing aids were on or not. But those having more difficulty with balance in this test performed better when their hearing aids were on. And the improvement in performance was even more apparent in the more challenging balance test.
“We wanted to see if we could detect an improvement even in people who did very well on the foam test,” Hullar said. “And we found, indeed, their balance improved during the harder test with their hearing aids on.”
Although patients could tell whether their hearing aids were on or off, the researchers randomized the order of the conditions in which each patient performed these tests, so that some performed the tests with hearing aids on first and some started with them off.
Hullar pointed out that many of the study patients did not report being consciously aware that they had performed better on these tests when their hearing aids were working. But he said he has heard anecdotal evidence that some people notice a difference.
“We wanted to find out if improved hearing really has a measurable effect on balance” Hullar said. “And the metric that we use—how many seconds can you stand on a piece of foam—has a well-documented relationship to risk of falling.” Hullar says that the research team intends to undertake a much larger study, and is seeking funding to do that.
Source: Washington University School of Medicine in St. Louis