The following information is from the Hearing Foundation of Canada:
Hearing loss is the fastest growing, and one of the most prevalent, chronic conditions facing Canadians today. While hearing loss has many causes, age-related (presbycusis) and noice-induced hearing loss (NIHL) are the two most common types. Here are some interesting statistics [that drive our work at The Hearing Foundation of Canada]:
- According to Statistics Canada, more than one million adults across the country reported having a hearing-related disability, a number more than 50% greater than the number of people reporting problems with their eyesight (StatsCan, 2002). Other studies indicate that the true number may reach three million or more Canadian adults, as those suffering from hearing problems often under-report their condition.
- One in five teenagers, aged 12 to 19 years, have some degree of hearing loss, according to a study by the American Medical Association from statistics from the NHANES 2005-2006 health survey. This represents a 30% increase over the preceding 10 years, and is at least partly attributable to noise damage (Shargorodsky et al, 2010).
- Based on a study from Tel Aviv University, 80% of teens use personal listening devices regularly, including 21% who listen to them 1 to 4 hours a day and 8% who listen for more than 4 hours, without a break. The findings of the study suggest that a quarter of the participants in the study are at severe risk for hearing loss (Muchnik et al, 2011).
- The cost of hearing loss to the Canadian economy could be in the tens of billions of dollars. A 2006 Australian study estimated that costs to that nation’s economy from hearing loss amounted to $10.6 billion per year. On a per capita basis, this could mean a Canadian equivalent of almost $18-billion per year.
- A major US study first published in the journal Paediatrics found that “approximately 12.5% of American children and young adults in the U.S. are suffering from a hearing disability known as noise-induced hearing threshold shifts (NITS). NITS is basically a change in hearing sensitivity that is experienced as temporary hearing dullness” (Niskar et al, 2001).
- Research shows that over the last 10 years, the percentage of second graders with hearing loss has increased by 280%, while hearing loss for eighth graders has increased over 400% (Montgomery and Fujikawa, 1992).
- A study in the Journal of the American Medical Association reported that nearly 15% of school-aged children had hearing loss. Seventeen percent of Americans have some degree of irreversible hearing loss. Harvard Stem Cell Institute scientists want to bring it back.
The ears are sensitive instruments that can be permanently damaged by such ubiquitous sounds as the roar of a motorcycle engine, the bang of a firecracker, or the din of construction work.
The cells that collect sound information from the environment and send it to the brain are called hair cells. We are born with about 11,000 hair cells in each ear, and they need to last. We experience the slow progression of hearing loss as these fragile cells die due to excessive noises, exposure to certain drugs, and aging. As hair cells die, nearby brain cells that once carried sound information to the audio processing part of the brain also expire.
About a third of 65-year-olds identify as hearing impaired, a number that rises to half by age 75. The only available treatments for hearing loss are prosthetic devices, such as hearing aids and cochlear implants. These devices can improve hearing, but they don’t always meet patients’ expectations.