10 Subjective Idiopathic Tinnitus in the Geriatric Population
Introduction
Tinnitus is the perception of sound in the absence of an external auditory stimulus; tinnitus can be distressing and annoying, contributing to disruption of sleep, anxiety, and depression.1 It has been reported that 16% of the general population have experienced tinnitus to some extent. 1About 25 to 30% of those who report tinnitus seek medical help; ~ 2 to 4% of all those with tinnitus report being unable to lead a normal life because of their tinnitus.1 Nearly a quarter of geriatric patients report tinnitus, a finding that has been stable for some time; the rate of distress and negative impact is higher than in younger patients, and the perceived severity increases with later onset of tinnitus.2–5
Tinnitus can be separated into two broad categories, objective and subjective. Objective tinnitus can be heard by both the patient and the examiner. It is less common than subjective tinnitus and can be caused by somatosounds. Subjective tinnitus is perceived only by the patient and may be idiopathic or secondary to another disorder. Tinnitus is commonly associated with hearing loss, traumatic brain injury, ototoxicity, and other conditions.1 When a diagnosis can be identified to which the tinnitus may be secondary, such as Ménière disease, otitis media, or cerumen impaction, treatment of the condition may provide improvement in the tinnitus.6,7 A significant percentage of tinnitus patients with normal hearing have abnormalities of outer hair cell function that can be measured by otoacoustic emissions, as well as abnormal central activity measured by auditory brainstem responses,8,9 and these cases are therefore not strictly idiopathic. Thus an effort should be made to identify any underlying conditions before making the diagnosis of idiopathic tinnitus. This review discusses subjective idiopathic tinnitus that is bothersome and that persists for longer than 6 months in the geriatric patient.
Evaluation
The evaluation of the geriatric patient with tinnitus does not differ significantly from that of other patients with hearing loss or tinnitus. A complete otolaryngological history is taken, and a physical examination is performed.6,10 In the geriatric patient, attention should be paid to family medical history (particularly to hearing loss history) past and present noise exposure (both recreational and work related), use of hearing protection, past and current medications, previous surgery, and past hearing aid use. It should not be assumed that geriatric patients are inactive and free of ongoing noise exposure. A history of arthritis, head injury, or smoking is associated with an increased risk of developing tinnitus.11 The concurrent complaint of anxiety and insomnia is also common in this population.12,13
A challenge in the evaluation of the geriatric tinnitus patient is the lack of a generally accepted instrument to document or describe the nature, severity, or quality of tinnitus. Visual analog scale scores can be used to assess loudness, pitch, and disturbance of the tinnitus. Questionnaires such as the Tinnitus Handicap Inventory and the Tinnitus Reaction can help with grading the tinnitus severity.1,14 The Tinnitus Functional Index has the advantage of being able both to grade tinnitus severity and to measure effectiveness of tinnitus interventions.1,15
Physical examination should include meticulous otoscopy (ideally with magnification), and audiological testing. Auscultation should be performed in complaints of pulsatile tinnitus. Audiological testing should not be limited to routine audiometry and tympanometry; otoacoustic emission testing and auditory brainstem response can help identify possible causes, even in those with normal routine audiometry.6,8,9 Laboratory tests such as autoimmune studies, tests for infectious causes (e.g., Lyme disease, syphilis), thyroid studies, hematocrit, blood chemistry, lipid profile, and others should be considered based on the level of suspicion created by the history and physical exam.6,16
Imaging is not performed routinely in elderly patients with symmetric hearing loss or tinnitus, nor in those with nonbothersome symmetric tinnitus without hearing loss. Imaging should be considered in patients with asymmetric hearing loss and tinnitus, asymmetric tinnitus without hearing loss, and pulsatile tinnitus.6,10 An excellent algorithm for the evaluation of pulsatile tinnitus is described by Mattox and Hudgins.17
Management
Despite the immense amount of literature on the management of tinnitus, there is a dearth of studies of sufficient quality to permit specific recommendations regarding treatment.1 Very little of the literature is specific to the management of tinnitus in the geriatric patient, and the studies that do exist are of insufficient quality to guide age-specific recommendations.
Currently there is no Food and Drug Administration (FDA)-approved pharmaceutical agent for tinnitus, and evidence-based pharmacological approaches are limited to the treatment of comorbidities such as depression, anxiety, and insomnia.18 Many medications recommended to assist in the management of tinnitus (antidepressants, anticonvulsants, anxiolytics, and herbal preparations) may be inappropriate or unsafe in the geriatric patient, and some may exacerbate tinnitus.1,19