Hearing Loss Screening Guidelines

Procedures

While a comprehensive analysis of diagnostic hearing evaluations and monitoring frequencies is beyond the scope of this activity, it is imperative that practitioners promptly refer children displaying hearing loss symptoms, possessing risk factors for early childhood hearing loss, or parental concerns about hearing issues to a pediatric audiologist for diagnostic testing.

Various methods are used for screening hearing loss tailored to different age groups. For infants, the recommended screening methods include auditory brainstem response (ABR), also called brainstem auditory evoked response, and otoacoustic emissions (OAE) testing. Behavioral audiometry evaluation is commonly utilized for screening in older children and adults.[8] These methods are essential for identifying hearing impairments across different stages of life.

Auditory Brainstem Response Test

Healthcare practitioners use ABR audiometry to assess the integrity of the pathway from the inner ear through the acoustic nerve to the brainstem. During the test, electrodes are attached to the patient's head, and earphones are inserted into their ears. As sounds are played, the electrodes monitor and record wave activity along the neural pathway. A significant advantage of the auditory brainstem response test, especially for infants, is that it does not necessitate active participation, making it highly effective in assessing hearing function early. 

Otoacoustic Emissions

During the OAE test, a tiny probe equipped with a microphone is inserted in the ear canal. Soft clicking sounds are emitted from the probe, and the response of the inner ear is measured using the microphone. OAE testing does not rely on patient behavior; it can be conducted on individuals while sleeping, enhancing flexibility and usability.

Behavioral Audiometry Evaluation

Behavioral audiometry evaluation comprehensively assesses the entire hearing pathway. This method involves evaluating patient responses to sound and necessitates active participation. For adults or older children, this might include raising a hand when a sound is heard. However, testing infants or toddlers presents unique challenges. In this case, behavioral responses are observed through subtler cues such as sucking on a pacifier, growing quiet, or actively seeking the source of the sound.

Pure-tone screening, a common form of behavioral audiometry evaluation, is predominantly employed in testing hearing in adults. This method assesses each ear using stimuli set at 25 dB across frequencies of 1000 Hz, 2000 Hz, and 4000 Hz. Should any abnormalities be detected during this screening, patients are promptly referred for further diagnostic evaluation.

Whispered Voice Test

The whispered voice test is a convenient evaluation conducted during an office visit. To perform this test, the patient sits while the practitioner stands at arm's length behind them. Each ear is tested individually, starting with the perceived stronger ear. The patient is instructed to block the auditory canal of one ear by pushing the tragus into the canal with their finger while simultaneously performing a circular rubbing motion to obscure the sound further. The practitioner then whispers 3 letters and numbers, and the patient is asked to repeat what they heard.[12] This process is repeated twice for each ear. The test is successful if the patient can correctly repeat at least 3 out of the 6 letters or numbers for each ear. Compared to audiometry in adults, the whispered voice test has demonstrated a sensitivity of 90% to 100% and a specificity of 80% to 87%.[13] In children aged 3 to 12, sensitivity slightly decreased from 80% to 96%, but specificity increased from 90% to 98%.

Alternatively, in adults, hearing loss screening can be as straightforward as asking, "Do you have difficulty with your hearing?" This simple question is often included in a Medicare annual wellness visit, providing a quick and effective way to initiate screening for hearing impairment.

A thorough physical examination of the ear, including the external ear, and an otoscopic examination of the ear canal and tympanic membrane is an essential part of the evaluation process. The examination may reveal common causes of temporary hearing loss, including cerumen impaction, fluid in the middle ear, or perforation of the tympanic membrane. Using a 512 Hz tuning fork, Weber's and Rinne's tests can help localize hearing loss to one ear, offering valuable clues indicating either a conductive or sensorineural hearing impairment.[8][14] Additionally, if available in the office, tympanometry, which is quick and straightforward, provides essential information about tympanic membrane compliance. Tympanometry can be useful in identifying issues like middle ear effusions or tympanic membrane perforations. 

Indications

Universal newborn hearing screening is strongly recommended to identify potential hearing issues early. All newborns should undergo hearing loss screening within their first month of life. Throughout childhood, the AAP recommends audiometry screening at ages 4, 5, 6, 8, and 10. During adolescence, the audiometry tests are recommended 3 times from ages 11 to 14, 15 to 17, and 18 to 21 years.[15]  Children displaying signs of hearing loss or concerning behaviors, delayed or garbled speech, difficulty following instructions, and excessively high volume on electronic devices should be promptly referred to a pediatric audiologist for comprehensive diagnostic testing. Signs of hearing loss in infants may include lack of startle to loud noises, lack of response to sound by 6 months of age, absence of speech by 12 months of age, and not responding to their name. 

Newborns who do not pass the initial hearing loss screening may require rescreening. Failure to pass can be due to debris like fluid or vernix in the ears, a noisy testing environment, or the baby crying or moving during the test. If a newborn repeatedly fails the hearing loss screen, it should be referred to a pediatric audiologist for diagnostic testing. The AAP recommends that diagnostic testing be completed by 3 months of age. If a hearing deficit is confirmed, prompt referral for intervention services is crucial and should be initiated by 6 months of age. Intervention services may include amplification, early intervention, medical/surgical evaluation, and parental support services.[1] To ensure early access to language stimulation and interventions for children with hearing deficits, some programs aim for screening to be completed by 1 month, diagnostic testing by 2 months, and interventions initiated by 3 months of age. 

Hearing loss screening is a crucial component of regular well-child visits. Parents should be asked if they have concerns about their child's hearing. Signs of hearing loss in babies may include a lack of startle to loud noise, failure to turn towards sound by 6 months of age, absence of single-word speech by 12 months, and not responding to their name. In older children, indicators may encompass delayed or unclear speech, difficulty following directions, and excessively high volume settings on electronic devices. The AAP also emphasizes the importance of identifying risk factors for early childhood hearing loss, which include a family history of permanent hearing loss, prolonged neonatal intensive care (>5 days), hyperbilirubinemia necessitating exchange transfusion, aminoglycoside exposure exceeding 5 days, instances of asphyxia or hypoxic-ischemic encephalopathy, in utero infections, and congenital malformations of the head, face or ears.

The screening guidelines for hearing loss in adults lack clear consensus. The US Preventative Service Task Force (USPSTF) has determined that evidence concerning hearing loss screening in adults is inconclusive, with no clear indication that screening leads to improved health outcomes.[16] Additionally, there is insufficient evidence regarding the potential harms associated with screening and treating hearing loss in adults. Conversely, the American Geriatrics Society advocates for the screening of all adults aged 65 years or older for hearing loss. The Centers for Medicare & Medicaid Services has acknowledged this recommendation, mandating practitioners to inquire about hearing impairment during the Medicare annual wellness visit. This can be accomplished by asking, "Do you have difficulty with hearing?" Furthermore, the American Speech-Language-Hearing Association suggests that adults undergo screening by an audiologist once per decade, increasing in frequency to every 3 years after the age of 50, especially for those with known exposures or risk factors associated with hearing loss.

Risk factors for hearing loss in adults encompass a variety of factors, including heredity, exposure to loud noise, head trauma or traumatic brain injury, falls, a history of ear infections, stroke, and certain chronic health conditions like diabetes, cardiovascular disease, and kidney disease. Additionally, ear disorders such as Meniere disease, otosclerosis, and autoimmune inner ear disease elevate the risk of hearing loss. Certain medications, known as ototoxic medications, can also contribute to hearing impairment. These include aminoglycosides, erythromycin, tetracycline, vancomycin, phosphodiesterase inhibitors, certain chemotherapeutic agents like cisplatin and 5-fluorouracil, and heavy metals including lead, mercury, cadmium and arsenic.[8][17] Adults expressing concerns about hearing loss or displaying signs of hearing impairment should undergo screening for early detection and appropriate intervention.

Normal and Critical Findings

Children with hearing screening results within the normal range can continue their routine care within their medical home. During well-child visits, healthcare practitioners should monitor their patients' developmental milestones and auditory skills and conduct regular otoscopic examinations. For children who exhibit deficits in these areas or if parents express concerns about their child's hearing, hearing loss screening is recommended. For children with abnormal hearing screening results, prompt referral to pediatric audiology for diagnostic evaluation is essential to ensure timely intervention and support.

Complications

Hearing loss screening is generally considered a low-risk procedure. Currently, there are no randomized controlled trials or controlled observation trials assessing the potential harms of hearing loss screening.[16] Potential risks associated with screening include unnecessary testing or treatment due to false-positive screening results. One potential harm of treatment could be the risk of exacerbating hearing loss through overamplification when using hearing aids. However, it is essential to note that this risk is rare due to the regulation of hearing aids as medical devices.

Clinical Significance

Undetected hearing loss in children can impede the development of speech, language, and social skills. Infants diagnosed by 3 months of age and who receive intervention by 6 months of age, according to the AAP Early Hearing Detection and Intervention program guidelines, exhibit notably higher vocabulary quotients than those who do not receive early diagnosis and intervention.[18]

Hearing loss can negatively impact a patient’s quality of life. Adults with hearing impairment may experience reduced independence and face challenges in understanding conversations, leading to increased social isolation. Individuals with hearing loss may have trouble understanding what others are saying. This can lead to increased social isolation. Hearing loss is also associated with higher rates of depressed mood, cognitive decline, dementia, falls, and hospitalizations.

The direct benefits of hearing loss screening for adults are limited, primarily due to a scarcity of studies and low rates of hearing aid utilization. Among adults diagnosed with hearing loss, fewer than 10% utilize corrective devices.[16] Although some evidence indicates improved performance on hearing-related function as measured by the Hearing Handicap Inventory for the Elderly Screening version (HHIE-S) scale, there is a lack of evidence for improvements in patient-centered outcomes such as quality of life, dementia, and cognitive impairment. Limited studies, primarily involving White male veterans, contribute to these constraints.

Despite challenges, clinicians play a pivotal role in implementing these guidelines, enhancing patient outcomes, and fostering a higher quality of life by promoting early detection, providing timely interventions, and facilitating necessary support systems. Their expertise not only improves individual well-being but also contributes significantly to public health initiatives, ensuring a society where hearing impairments are identified and managed effectively, leading to improved overall health and societal inclusivity.