Young people show rising rates of hearing loss

When Chattanooga ear, nose and throat specialist Dr. David Armstrong walks into an examining room and hears music buzzing from a young patient’s earphones, he doesn’t hesitate to issue a warning.

“The cells in the ear that convert that sound energy into a nerve signal that can be picked up by a brain — those cells are the only cell of that type in your body. You don’t generate more of those,” he said.

The damage being done could be permanent, he said.

An aural assault on teenagers’ ears — from music concerts to the prolonged use of MP3 players such as Apple iPods cranked up to max volume — could be one source of a worrisome trend.

Today, 6.5 million Americans between ages 12 and 19 — one in five — have at least “slight” hearing loss, according to a study published in August in the Journal of the American Medical Association.

That’s up more than 30 percent since the 1990s. Researchers compared findings from the National Health and Nutrition Examination Survey from 1988-94 and 2005-06.

Children living under the poverty threshold were more likely to have hearing loss, and boys were more at risk than girls, according to the study, conducted at the Brigham and Women’s Hospital in Boston.

Most of the hearing loss identified was minor, but even mild loss can impair speech and language development, educational achievement and social development, the authors said.

Lead study author Josef Shargorodsky called the increase in hearing loss “surprising.” He said researchers had thought they might see a reduction in hearing loss, because of improvements in treating and preventing ear infections.

The effects of minor hearing loss might not be obvious. Parents might notice that it takes more than one try to get their child’s attention, or that their adolescent’s school performance is suffering, local hearing experts said.

Teens might turn up the TV volume or have difficulty understanding whispers and distinguishing between consonant sounds such as p, d, t and s, Armstrong said.

The study didn’t identify causes for the increase, but some experts think that portable music devices such as iPods, which easily can exceed 100 decibels, are playing a role.

“I have begun to see some children ... who do have some degree of hearing loss,” said Denise Sheppard, audiologist at Dalton Ear Nose and Throat. “It was my first impression that noise was probably the culprit.”

Researchers said other factors such as side effects from medications and nutrition need further investigation.

On the University of Tennessee at Chattanooga campus, ear buds and headphones are everywhere, senior Jeff Smith, 24, said Friday. He was listening to rapper Wiz Khalifa on his iPod as he waited for the bus.

“You need something to get you from point A to point B,” he said. Instead of ear buds, he uses headphones that block out background noise and let him keep his music’s volume lower.

Freshman history major Michael Welty, 18, was listening to Rage Against the Machine on his iPod as he walked through campus last week. He said the recent study’s results don’t surprise him, considering iPod users’ habits.

“If you’re gonna sit and blast it in your ears for 20 minutes or more, you’re going to do some damage,” he said.

Doctors recommend avoiding long exposure to noises louder than 85 decibels. That’s the noise level found on a busy street corner in Times Square, New York, or riding in a convertible on the highway, Shargorodsky said.

He said there’s evidence that youthful hearing loss could lead to greater damage from noise later in life.

“We don’t know what the hearing is going to be like in this age group in 40 years, but there’s data out there that shows it is progressively going to get worse,” he said.

Parents can use Apple’s volume limit setting for some iPods, Shargorodsky said.

“But I wouldn’t blame the iPod; it’s how you use it,” he said.

Welty, an aspiring musician, said he doesn’t worry too much about his iPod volume level: He hopes to spend years on stage with an amplifier blasting music behind him, anyway.

“By the time I’m 50, I’m going to be like, ‘What?’” he said.