Tinnitus can be a debilitating condition that affects quality of life and is often not treated according to guidelines. Cognitive behavioral therapy and tinnitus retraining therapy have been successful in reducing tinnitus bother; pharmacotherapy is not widely accepted as successful, and can, in fact, be deleterious. This article describes pathophysiologic disturbances of hearing and how they relate to chronic subjective tinnitus, discusses the clinical evaluation of tinnitus as a presenting symptom, and reviews current treatments.
Primary chronic subjective tinnitus, often thought of more as a symptom than a diagnosis, affects millions of people worldwide. This troublesome condition has been chronicled as far back as the first century ad, when Celsus gave detailed accounts in his treatise, De Medicina.1
It is estimated that only 20% of people who experience tinnitus actively seek treatment.2 In the United States, 2 to 3 million of the 12 million patients who do request treatment report lasting symptoms that they describe as debilitating.3 For patients who seek help, the treatment recommended by physicians is typically pharmacotherapeutic—which does not follow guidelines.4
The aim of this article is to reinforce a greater understanding of the mechanisms of tinnitus and integrate that knowledge into treatment guidelines. The article does not discuss surgical treatment of tinnitus.
DEFINITION AND CLASSIFICATION
A universal standard definition of chronic tinnitus does not exist; Trevis et al define it as a phantom sound that persists for more than three months.5 The quality and loudness of tinnitus is variable but is often described as a buzz, hiss, or ringing. Prevalence increases with age, smoking, male gender, and ethnicity, with the non-Latino white population statistically at greater risk.3 Comorbid conditions (eg, diabetes and other autoimmune diseases) are risk factors for tinnitus. A history of exposure to loud sound—occupational, environmental, or recreational—also can predispose a person to tinnitus.3
The American Academy of Otolaryngology–Head and Neck Surgery (AAO–HNS) classifies tinnitus as primary (subjective) or secondary (objective). Primary tinnitus—representing the majority of cases—has no identifiable cause; there may be accompanying sensorineural hearing loss or hyperacusis. Secondary tinnitus can also be associated with sensorineural hearing loss but has an identifiable underlying cause.6 The differential diagnosis of tinnitus is listed in the Table.7
Tinnitus is further defined by its persistence. Persistent tinnitus is defined as tinnitus lasting more than six months, slightly longer than the duration offered by Trevis et al, who also define tinnitus as bothersome or non-bothersome, depending on its impact on quality of life.5,6 Causes of reduced quality of life include depression, anxiety, insomnia, and neurocognitive decline—all of which have been associated with chronic subjective tinnitus.8
Continue to: Researchers have discovered that...