October 14, 2013

A thorough audiological examination should begin with a careful medical history. Along with the actual presenting complaint or symptoms, listening to past history is an important early step in helping determine the source of the patient’s problem. Hearing health risk factors are any and all pieces of information about a patient’s history that suggest increased likelihood of a problem with the ears or hearing. Obviously, conditions such as a hernia or sprained ankle are not likely to be related to hearing. There are, however, many conditions, diseases or lifestyle choices that can affect the ears. These should be known to the examiner if we wish to understand the patient’s condition fully.

Let us examine some risk factors for hearing.

  • Family history. Having relatives with ear conditions (not otherwise explained by environmental factors, such as lifestyle or occupation) increases the likelihood of problems. Genetic factors may be at work.
  • Noise exposure. OSHA workplace regulations limit allowable noise exposure times beginning at 85 decibels. Sound intensity and duration of exposure interact to produce safe or unsafe “doses” of exposure. The mechanism of noise damage will be the topic of a future article, however, the public needs to be aware that activities such as lawn mowing, live music, extensive headphone use, power tool use, firearms use, factory work and even attendance at events with massive live audiences (such as NFL games) can produce inner ear damage.
  • Toxicity. Many medications, such as certain classes of antibiotics (particularly aminoglycosides), chemotherapy agents, diuretics, quinine, analgesics and even erectile dysfunction drugs can be harmful to the ears. Environmental substances, such as toluene, may also be toxic to hearing and/or balance function.
  • Illness. Diseases such as diabetes, meningitis, vascular conditions, otosclerosis, Eustachian tube dysfunction, Meniere’s disease, labyrinthitis, autoimmune conditions and many others are associated with increased risk for hearing loss.

Often the above risk factors can interact. For example a noise exposed person with a family history of hearing loss working with toxic chemicals is certainly at higher risk when all these factors are taken into consideration. Any individual who suspects multiple risk factors needs to exercise even greater vigilance in protecting and monitoring his or her hearing. This should include periodic audiometric evaluations.