Hearing Loss and Teens

Last month, the Journal of the American Medical Association stunned America when the publication announced the results of a recent hearing study conducted on teens.

The study showed that one in five teens exhibited a slight loss of hearing, affecting only one ear and involving mostly high-frequency sound. One in twenty teens, however, showed "moderate, progressive" loss.

"It's not a stretch to attribute these losses to the prolific use of loud-playing MP3s, concert attendance and other environmental factors," noted Dr. Mary Bohr, Director of Audiology at McGuire's Hearing Aids and Audiological Services.

"One of the best ways to combat this trend is to educate teens and their parents about healthy hearing habits," she added.

Scientists believe that, depending upon the type of noise, the pure force of vibrations from loud sounds can cause hearing loss. Recent studies also show that exposure to harmful noise levels triggers the formation of molecules inside the ear that contribute to hair cell damage and noise-induced hearing loss, or NIHL. These destructive molecules play an important role in hearing loss in children and adults who listen to loud noise for too long.

NIHL occurs based on three factors the decibel level (loudness) of a sound; the amount of time you are exposed to it; and the distance you are from the source of the sound. In addition, the impact of noise adds up over a lifetime. If you are exposed to loud sounds on a regular basis, your risk for permanent damage adds up as you age.

NIHL is also related to a person's genes. Some people are more likely than others to develop NIHL when they listen to certain sounds. Scientists are working to determine why some people are more at risk for NIHL and why some face less risk. For this reason, it is wise to protect our hearing when we are exposed to loud noise.

Researchers who study hearing loss in the workplace have found that a person who is exposed to noise levels at 85 decibels or higher for a prolonged period of time is at risk for hearing loss. An MP3 player at maximum level is roughly 105 decibels. Scientists recommend no more than 15 minutes of unprotected exposure to sounds that are 100 decibels. In addition, regular exposure to sounds at 110 decibels for more than one minute can result in permanent hearing loss.

Dr. Bohr advises patients to avoid risking NIHL by practicing the following:

• block loud noises by wearing headphones, earplugs or earmuffs
• purchase earbuds that offer a custom fit for you and allow optimal MP3 use without excessive volume . Newly developed earbuds are now available at McGuire's which actually control the loudest sounds from MP3 and IPods so that they never exceed allowable limits.
• avoid the noise by distancing yourself from the source or leaving an area entirely
• cover your ears with your hands if exposed to loud environments temporarily
• turn down the volume of MP3s, stereos, or other devices that emit loud sounds

"If you believe you may have a hearing loss, contact a certified audiologist who offers a free hearing screening with no obligation," Dr. Bohr suggested. "Only a professional hearing practitioner can determine if you have a hearing loss and offer solutions for better hearing," she noted.

Study Links Exposure to HIV in Womb To Later Hearing Loss

Children exposed to HIV in the womb may be more likely to experience hearing loss by age 16 than are their unexposed peers, according to scientists in a National Institutes of Health research network.

The researchers estimated that hearing loss affects 9 to 15 percent of HIV-infected children and 5 to 8 percent of children who did not have HIV at birth but whose mothers had HIV infection during pregnancy. Study participants ranged from 7 to 16 years old.

The researchers defined hearing loss as the level at which sounds could be detected, when averaged over four frequencies important for speech understanding (500, 1000, 2000, and 4000 Hertz), that was 20 decibels or higher than the normal hearing level for adolescents or young adults in either ear.

"Children exposed to HIV before birth are at higher risk for hearing difficulty, and it's important for them—and the health providers who care for them—to be aware of this," said George K. Siberry, M.D., of the Pediatric, Adolescent, and Maternal AIDS Branch of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the NIH institute that leads the research network.

Compared to national averages for other children their age, children with HIV infection were about 200 to 300 percent more likely to have a hearing loss. Children whose mothers had HIV during pregnancy but who themselves were born without HIV were 20 percent more likely than to have hearing loss. The study was published online in The Pediatric Infectious Disease Journal.

"If parents and teachers know the child has a hearing problem, then they may take measures to compensate in various communication settings, such as placement in the front of the classroom or avoiding noisy settings," explained Howard Hoffman, M.A., director of the Epidemiology and Statistics Program at the National Institute on Deafness and Other Communication Disorders (NIDCD), which provides funding to the network for studies related to hearing and language.

Even a mild hearing loss in children can delay the acquisition of language skills. More severe hearing loss may require the use of assistive devices, such as a hearing aid. Information on hearing and deafness is available from NIDCD.

To determine the types of hearing loss the children experienced, the researchers conducted these evaluations:

• Physical examination of the ear canal
• Evaluation of the middle ear function, how sound vibrations are transmitted through the middle ear bones
• Responses to tones presented over earphones

Hearing loss may occur from damage to the bones and structures in the ear canal and inner ear, or from damage to the nerves leading to the brain.

First author Peter Torre III, Ph.D., of San Diego State University, led the study with Hoffman, Siberry and six other coauthors. Collaborators were from the Harvard School of Public Health, Boston; the University of Kansas, Lawrence; and Tulane University School of Medicine, New Orleans.

The research was conducted as part of the Pediatric HIV/AIDS Cohort Study network, led by NICHD in cooperation with and with cofounding from NIDCD and several other NIH institutes, including: the National Institute on Drug Abuse, the National Institute of Allergy and Infectious Diseases, the National Institute of Mental Health, the National Institute of Neurological Disorders and Stroke, the National Heart Lung and Blood Institute, and the National Institute on Alcohol Abuse and Alcoholism.

More than 200 children and teenagers participated. All had been exposed to HIV before birth, and about 60 percent were HIV-positive at the time of the study. Researchers conducted hearing tests on the children if their parents or caregivers had reported hearing problems, they had low scores on a standard test of language or their health care providers detected hearing problems during standard hearing screenings.

The researchers classified participants who could not hear tones below a certain volume as having hearing loss with difficulties in quiet and noisy settings. The researchers documented a greater proportion of hearing loss cases among HIV-positive children and found that those who had developed AIDS at any point were even more likely to have hearing loss—even if the disease was under control at the time of the study.

Earlier studies have found that children with HIV are susceptible to middle ear infections. Repeated middle ear infections can cause hearing loss. However, in 60 percent of cases in the study, hearing loss was the result of problems with the transmission of sound from the nerves of the ear to the brain, rather than to damage in the middle ear resulting from ear infections.

"Although ear infections are more common among children with HIV, these do not appear to be the reason their hearing is more likely to be compromised," said Torre.

Hearing Aids Reduce "Ringing" In The Ears

A new study recently conducted by the Better Hearing Institute (BHI) has found that nearly thirty million Americans – or ten percent of our population – suffer from chronic tinnitus, or "ringing in the ears."

In fact, tinnitus was recently indicated to be the number one service-connected disability of military personnel returning from service in Afghanistan or Iraq.

Sufferers of tinnitus generally describe the noise as a ringing, a humming, or a buzzing. The sound can be constant or intermittent, and in one or in both ears.

"Persistent, chronic tinnitus is a highly intrusive, increasingly common condition that can interfere with a person's cognition, ability to interact with family and friends, and basic life functions," stated Jennifer Born, study co-author and the Director of Public Affairs at the American Tinnitus Association.

The leading cause of tinnitus is extreme exposure to noise. Those suffering from the condition almost always have hearing loss in conjunction with tinnitus. Yet, the researchers involved the study were surprised by the number of respondents who initially reported that they had tinnitus, but no hearing loss. After testing them, however, the study authors discovered that the majority of the respondents did, indeed, have hearing loss.

"It's very likely that these individuals were aware of their tinnitus but not their hearing loss – which would indicate that the population with hearing loss is much larger than previously believed," noted study co-author Dr. Sergei Kochkin.

"People suffering with tinnitus should seek the counsel of an audiologist so that appropriate remedies are explored," said Dr. Mary Bohr, Director of Audiology at McGuire's Hearing Aids and Audiological Services. "It's quite possible that a patient's tinnitus can be helped by hearing devices."

Hearing loss may be an early sign of dementia

This story appeared originally on CNN.com on this web page.

Gradual hearing loss is a common symptom of aging, but in some people it may also be an early sign of Alzheimer's disease or other types of de

mentia, a new study suggests.

The risk of dementia appears to rise as hearing declines. Older people with mild hearing impairment -- those who have difficulty following a conversation in a crowded restaurant, say -- were nearly twice as likely as those with normal hearing to develop dementia, the study found. Severe hearing loss nearly quintupled the risk of dementia.

It's unclear why the loss of hearing and mental function might go hand in hand. Brain abnormalities may contribute independently to both conditions, but it's also possible that hearing problems can help bring on dementia, the researchers say. Hearing loss may lead to social isolation (which itself has been linked to dementia), for instance, or it may interfere with the brain's division of labor.

"The brain might have to reallocate resources to help with hearing at the expense of cognition," says the lead researcher, Frank R. Lin, M.D., an ear surgeon at Johns Hopkins Hospital in Baltimore. That may explain in part why straining to hear conversations over background noise in a loud restaurant can be mentally exhausting for anyone, hard of hearing or not, he adds.

The findings suggest that poor hearing is a "harbinger of impending dementia," says George Gates, M.D., a hearing expert at the University of Washington in Seattle, who was not involved in the new study but whose own research has demonstrated a link between the two conditions.

"We listen with our ears but hear with our brains," Gates says. "It is simply not possible to separate audition and cognition."

In the study, which appears in the Archives of Neurology, Lin and his colleagues followed more than 600 dementia-free adults between the ages of 36 and 90 for an average of 12 years. A little less than 30 percent of the study participants had some hearing loss at the start of the study.

Overall, 9 percent of the participants went on to develop Alzheimer's disease or another form of dementia. Mild, moderate, and severe hearing loss were associated with a two-fold, three-fold, and five-fold higher risk of later dementia, respectively, in comparison to normal hearing.

People with moderate hearing loss generally struggle to communicate even in quiet settings, and those with severe hearing loss are near deaf.

Lin says that hearing loss has an enormous impact on the lives of his patients and their family members. "Yet because it is such a slow and insidious process, it is often left ignored and untreated."

Whether hearing aids or other treatments (such as cochlear implants) can help stave off dementia is the "50 billion dollar question," Lin adds. Thirty million Americans currently have impaired hearing and 1 in 30 are predicted to suffer from dementia by 2050, so if those treatments prove to be helpful, their impact would be felt widely.

There is no cure for dementia, and there are no surefire ways of preventing it. Gates isn't optimistic that restoring hearing can affect the course of dementia. However, if treatments and prevention strategies for dementia do become available in the future, he says, hearing loss could play an important role in early detection.

Lin and his colleagues have begun researching the effect of hearing aids on the risk of dementia. "Whether or not it can help dementia, we don't know yet," he says. "But in the meantime, there's no reason not to take your hearing loss seriously and pursue some type of treatment."

Hearing and Heart Health

For many people, hearing loss occurs with age. This is manifested in two ways: first, we begin to lose sensitivity to sound; second, our ability to clearly understand speech declines, even when the speech is loud enough to hear comfortably.

Statistically speaking, hearing loss is the third most prevalent chronic health condition, after arthritis and cardiovascular disease. It's even more prevalent that vision problems.

Most people know that hearing loss can occur due to noise exposure and aging. However, other factors, such as disease, medications, genetics, anoxia, and even cardiovascular disease can contribute to hearing loss, and a number of studies back this assertion.

The ear requires a rich blood supply in order to function well. When the blood supply is interrupted, as in chronic cardiovascular disease, for instance, or even in the course of some cardiovascular procedures, it causes changes to the structures of the ear including the stria vascularis, the Organ of Corti and the internal auditory artery. Subsequently, hearing is affected.

Studies have shown that adults 65-85, with a history of cardiovascular disease had significantly poorer hearing than people without cardiovascular disease. Interestingly, when studies look at myocardial infarctions, women seem to be affected more than men. Some clinicians have even suggested that hearing loss may be an early marker for cardiovascular disease because hearing loss seems to precede heart disease.

Other studies have evaluated subjects who did not have cardiovascular disease, and the results indicate that these heart-healthy individuals with excellent muscle tone have better hearing as well.

It has been suggested that good muscle strength and excellent cardiovascular health may, in fact stave off hearing loss and maintain good hearing sensitivity longer because of increased flow of oxygen, and increased glucose supply to all the organs and structures of the auditory system.

There is also evidence that regular exercise may play a role in hearing conservation through improvements in circulation.

Though a number of studies have investigated the interconnection between cardiovascular health and hearing sensitivity, there is no consensus on the topic. This evidence to date prompts us to examine more closely the relationship of cardiovascular fitness level and hearing. Hearing health notwithstanding, cardiovascular fitness has its own rewards through greater overall physical and mental health.

Hearing Loss: When To Get It Checked

Did you hear the one about the woman who gently patted her husband's hand and said, "Dear, I've been suggesting for some time that you have your hearing checked, and you've simply ignored me. I know it isn't easy..." Her husband looked at her and shouted, "WHAT?!?"

For some people, acknowledging a hearing loss is a difficult admission. But there are some suggested guidelines.

It's time to see a licensed hearing professional when...

• You experience muffled hearing.
• You can't distinguish specific words when someone is speaking, especially when there are competing voices or noises in the background.
• A higher volume is required on the television, radio or MP3 player than in the past.
• You avoid conversation and social interaction for fear of lack of hearing.
• You experience vertigo in conjunction with hearing loss.
• People get annoyed with you because you misunderstand conversations.
• You are concerned about missing a phone call or doorbell.
• You get confused about where sounds come from.

"It's not always easy for patients to admit that they have a hearing loss," noted Dr. Mary Bohr, Director of Audiology for McGuire's Hearing Services. "Some patients feel that they can compensate for this limitation without hearing devices, but it's not really possible. Hearing loss simply gets worse with time," she added.

"The bright side is that we now have access to dozens of hearing aid styles, sizes and colors. This assortment allows self-conscious patients to wear hearing devices that can barely be detected, and are customized based on a patient's specific needs," she observed.

The technology of hearing devices has improved significantly in the past few years, and manufacturers report the use of digital devices and components that are approaching nano-sized elements.

"Once patients realize the advanced technology and the variety of devices suited to their lifestyles, they are much better about wearing a hearing instrument," Dr. Bohr concluded.

Secondhand Smoke: Firsthand Health Issues

Secondhand smoke has been linked to an increased risk in hearing loss among persons aged 12 - 19, according to a study that was conducted in 2005 – 2006.

Although the National Health and Nutrition Examination Survey (NHANES) was conducted several years ago, interviews with participants have just been completed, allowing researchers to better understand secondhand smoke and its impact on young adults.

The study evaluated 1,533 teens. Those who had exposure to secondhand smoke exhibited notably higher rates of low and high frequency hearing loss, as compared with those who had no exposure to secondhand smoke. In fact, nearly 82% of the afflicted teens did not recognize their hearing difficulties.

The study participants also underwent a battery of physical tests, including blood testing for cotinine, a by-product of nicotine exposure. Researchers noted that the rate of hearing loss appeared to be cumulative, and appeared to increase with the level of serum cotinine found in the blood of study participants.

"Secondhand smoke has been a suspect in hearing loss among young adults for quite some time," noted Dr. Mary Bohr, Director of Audiology at McGuire's Hearing Aids and Audiological Services.  "The study confirms the detrimental effects of secondhand smoke among this population, and reinforces the belief that smoking is dangerous for people other than the smoker," she added.

"Adolescents exposed to (secondhand smoke) may need to be closely monitored for early hearing loss with periodic audiologic testing," study researchers cautioned.