Tinnitus is considered a symptom and not a diagnosis. It varies in its presentation from unilateral to bilateral and intermittent to constant. Typically, it is of unknown etiology but can be due to a secondary medical condition. Work up should include obtaining a detailed history and performing a focused physical examination as well as assessment of potential concomitant hearing loss as these often go hand in hand. Management includes helping the patient cope with their tinnitus using tools such as cognitive behavioral therapy among others. Education is also crucial to help patients understand and overcome the challenges associated with this symptom.
Key points
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Tinnitus is often seen in primary care offices but is challenging to manage.
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Tinnitus can affect a patient’s quality of life.
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Although there are many potential causes of tinnitus, many cases are of unknown etiology.
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There is no gold standard in terms of curative treatment.
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Depending on cause, there are measures that may help improve living with tinnitus.
Introduction
Tinnitus, derived from the Latin word “tinnire,” manifests as a perception of ringing or other sounds, such as “buzzing” or “hissing” in the ears without an obvious external source. It is a common symptom encountered by primary care physicians, with prevalence estimates in the United States ranging from 10% to 15%. , Tinnitus varies widely among individuals, presenting as unilateral or bilateral, with fluctuations in intensity and frequency that can be intermittent or continuous, lasting from a few minutes to being constant. It is not specific to any single disease and lacks a definitive pathophysiological mechanism, which complicates the identification of underlying causes. The severity of symptoms can range from mild irritation to significant distress.
Despite advancements in treatment, there is currently no known cure for tinnitus although it can be improved or sometimes remit depending on the etiology. When persistent, it often adversely affects quality of life for patients, potentially leading to psychological distress and impacting daily functioning. Moreover, tinnitus places a substantial burden on both clinical resources and health care economics. In 2023, it was reported as the most compensated service-connected disability among US veterans.
This article highlights the pervasive nature of tinnitus, its impact on individuals, and current recommendations in management.
Incidence/prevalence
According to the National Health Interview Survey, in 2014, the prevalence of tinnitus in the United States was 11.2% with a range of 10% to 15% in adults. The rate may actually be higher as not all patients seek care for this. In this survey, the rates were higher among non-Hispanic Whites versus other ethnicities and men versus women. Prevalence is known to be higher in older adults with peak occurrence in the 60 to 69-year-old age group but the distribution between men and women is equal, although men report the symptom more often. Some studies show that only 1 in 5 people may seek care at some point, which means the majority individuals with tinnitus may suffer in silence.
Classifications
Tinnitus is classified based on whether the sound is perceptible only to the patient (subjective tinnitus) or can be heard by someone else, typically a physician using a stethoscope (objective tinnitus). Subjective tinnitus is the most prevalent type and is often linked to damage along the auditory pathways. In contrast, objective tinnitus, occurring less frequently, typically originates from a mechanical source such as muscular or vascular. When the cause is related to muscular, it involves one of the ears, nose, and throat muscles and will often be described as “clicking” in nature, whereas, a vascular source due to turbulent blood flow will be pulsatile. Further classification involves determining whether an underlying cause can be identified. Primary tinnitus refers to cases where no specific cause is known, often termed idiopathic. While primary tinnitus may be associated with sensorineural hearing loss (SNHL), this connection is not necessary. Patients with primary tinnitus often find this symptom frustrating due to the absence of identifiable pathology and its impact on their lives.
On the other hand, secondary tinnitus usually results from an identifiable underlying condition or etiology, although it occurs less frequently than primary tinnitus. Management of secondary tinnitus focuses on addressing the root cause contributing to the auditory perception.
It is essential to note that these classifications may overlap: subjective and objective refer to the perception of sound, while primary and secondary describe whether an underlying cause can be determined. Understanding these distinctions aids in tailoring appropriate diagnostic and therapeutic strategies for patients affected by tinnitus.
Etiologies
The mechanism or pathophysiology of subjective tinnitus is not clearly understood and in fact may be due to more than 1 cause. Multiple studies suggest that the dysfunction being in the cochlea and then an imbalance of neural activity is generated in the central pathway with a resultant perception of the abnormal sound of tinnitus. If the auditory system is involved over a longer period of time in these patients, the limbic system becomes affected as does the autonomic nervous system. Depending on location of the abnormalities, secondary changes occur which are hypothesized to explain the differences in pitch and volume of the tinnitus over time. ,
Hearing Loss
Subjective tinnitus tends to be associated with hearing loss (SNHL) without any other linked cause. Some studies denote tinnitus as a threshold phenomenon in which tinnitus arises from 1 factor, for example, chronic hearing loss and it becomes symptomatic upon the emergence of multiple trigger factors acting in a synergistic fashion. ,
Noise Exposure
Data based on population studies reveal that loud noise exposure is one of the most common causes of tinnitus. Following noise exposure or trauma, the outer hair cells undergo temporary changes that increase gain in the central auditory system. Subsequently, the microstructures of the cochlea become damaged resulting in tinnitus. It is important to note that the environment stimulus can consist of either a single exposure to a loud noise/trauma or chronic exposure over time.
Age
Tinnitus can occur if there is reduction in auditory function as a result of age or if there is an abnormal lesion in the auditory pathway as a result of aging. Presbycusis is linked to bilateral subjective tinnitus but because of the age representation (60–60 years), consideration should be given that there is a vascular component contributing as well. Hearing tends to regress at age 60, involving sensory loss of high- frequency sounds and tinnitus is most commonly found in this demographic, according to the American Tinnitus Association. ,
Ototoxicity
There are a number of medications that have some association with tinnitus. When tinnitus occurs in conjunction with otoxicity from medications, it typically manifests as bilateral and subjective. While often transient and reversible upon stopping the drug, higher doses may result in permanent tinnitus.
See Fig. 1 – for medications associated with tinnitus.
Medical conditions
Tinnitus is not known to be pathognomonic for any 1 disease state but can occur in conjunction with other symptoms in an array of conditions, ranging from neurologic (head injury, schwannoma, multiple sclerosis, acoustic neuroma) to infectious (neurosyphilis, meningitis, otitis media) to other disorders (hypothyroidism, anemia, Lyme disease, idiopathic intracranial hypertension, arteriovenous malformation).
Other relatively common associations include: presbycusis, chronic noise exposure, cerumen impaction and systemic hypertension.
Evaluation
History and Initial Assessment
It is important to discern what type of tinnitus the patient is experiencing, as some causes will warrant further evaluation acutely and maybe harmful, such as those due to critical conditions such as carotid dissection or severe trauma. Classification begins via obtaining a thorough pertinent history with specific history questions and a focused physical examination.
Once tinnitus is initially determined to not be emergent, it should be classified as pulsatile or non-pulsatile as this determines the potential causes affiliated with each. Pulsatile tinnitus, in which one perceives the tinnitus to be in synchronous with their heartbeat, tends to be less common than non-pulsatile with etiologies that include: systemic hypertension, vascular tumors, ateriovenous malformation, sinus venous thrombosis and idiopathic intracranial hypertension.
Further delineation of non-pulsatile tinnitus involves determining whether or not hearing loss is present and finally, duration along with associated symptoms helps stratify.
Severity is noted as “mild,” “moderate,” or “severe”.
Location is assessed as “unilateral” or “bilateral” with the former signifying concern for structural lesions in the auditory region.
Duration is described as “acute” (<6 months) or chronic” (>6 months), with chronic being less likely to remit. In acute tinnitus, there may be an identifiable cause that is reversible.
Character should be noted and maybe described as “ringing” which is the classic quality but also might be “hissing” or “buzzing.” These descriptions are typically associated with primary tinnitus whereas a “roaring” is usually indicative of a secondary cause.
Pulsatile or rhythmic clicking are both associated with neurologic conditions and warrant prompt referral. Also, if the tinnitus varies with change in physical activity or position, this can be related to neuro or vascular etiology.
Past medical history should be assessed for factors such as noise exposure, which can be occupational or social, acoustic trauma or injury, and medication use.
Finally, the presence (or absence of) associated symptoms should always be ascertained. These includes hearing loss, vertigo, ear pain, ear drainage, and imbalance as well as any that related to suspected differential diagnoses.
Validated questionnaires were developed to evaluate the disabling consequences of tinnitus and that can be used to determine impact of the symptom for use in the clinical setting and/or in the research arena. These consist of Tinnitus Handicap Inventory (for clinical trials), Tinnitus Reaction Questionnaire, Tinnitus Functional Index, and Tinnitus Primary Functions Questionnaire. Using these tools helps to distinguish between bothersome and non-bothersome tinnitus, with the latter not having a great impact on the quality of life and not requiring intervention.
It is vital to identify and treat concomitant disorders such as anxiety and depression as they can further impact quality of life in patients with tinnitus.
Physical examination
A focused physical examination including head, eyes, ears, nose, and throat should be performed; neurologic, cardiovascular, vascular, and musculoskeletal are the important systems that should be assessed as key findings may potentially lead to source of tinnitus.
Key findings in physical exam that may aid in diagnosis include:
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Cerumen impaction
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Foreign body
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Otitis (media or externa)
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Nystagmus
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Papilledema
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Visual field defects
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Ataxia
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Carotid bruit
There is also a grading scheme that can help delineate subjectively the degree of tinnitus the patient is experiencing in terms of impact on life. See Fig. 2 for- Grading scheme.
