EARN CPD OR PDP POINTS 15 Complete How to Treat quizzes via ausdoc.com.au/howtotreat How to Treat. PULL-OUT SECTION NEED TO KNOW Hearing loss is classified as con- ductive, sensorineural, or mixed. Though hearing loss is prevalent, it should not be viewed as a nor- mal part of ageing. Identifica- Earn CPD or PDP points. tion and treatment of hearing loss helps improve quality of life. Go to ausdoc.com.au /howtotreat Age-related hearing loss is the most common cause of hear- ing loss in the elderly, but there are numerous other differential diagnoses. Note the association between age-related hearing loss and dementia, and encourage patients to seek treatment for their hearing loss. Screen for cognitive decline as indicated. Refer for specialist assessment in cases of asymmetric senso- rineural hearing loss, any con- ductive hearing loss, neurologic deficits, severe otologic symp- toms, profound hearing loss and difficulty hearing despite well-fitted hearing aids. Hearing aids are often pre- scribed once it has been decided there is no further medical or surgical intervention. Devices have differing indications and specific eligibility requirements. Hearing loss in the elderly BACKGROUND with hearing difficulties.5 and hearing loss was first described those with established dementia do ONE in six Australians are currently Hearing loss remains under- in 1989, when a case-control study not show the same reversal effect.11 affected by hearing loss, and as recognised and undertreated. It is demonstrated a greater prevalence Though the data is preliminary, it many as one in four are anticipated estimated that only one in four of of hearing loss in 100 patients with would seem to suggest that earlier Dr. Andrew Ma (left) to be affected by 2050 as the popu- those who would benefit from a hear- Alzheimer’s disease vs 100 matched identification and treatment of hear- Otology/Neurotology fellow, Royal North Shore lation ages.1 Hearing loss affects 37% ing aid have one.1 controls without dementia.6 ing loss may have a protective effect Hospital, Kolling Deafness Research Centre, of adults older than 60 and 80% of Although ARHL is the over- In 2011, a landmark prospective against dementia onset. Macquarie University and University of Sydney, adults older than 80.2 whelming cause of hearing loss in the study demonstrated a strong associ- The prevalence of hearing loss Sydney, NSW. Globally, the burden of hearing elderly, there are myriad other poten- ation between pre-existing hearing and cognitive impairment is likely to loss is significant, with more than tial causes that require recognition loss and risk of dementia onset.7 The continue increasing over time due to Dr. Nicholas Jufas (centre) 5% of the world population (360 mil- and appropriate referral for specialist study found that untreated hearing the increasing ageing population. It is Clinical Associate Professor, Kolling Deafness Centre, Macquarie University and University of lion people) experiencing disabling management. loss increased the risk of dementia therefore vital for GPs to be aware of 3 Sydney, Sydney, NSW. hearing loss. According to WHO esti- The aim of this How to Treat is to onset by approximately 35%. the link between dementia and hear- mates, there may be as many as 500 review the aetiologies, workup, and Additional research has exam- ing loss. Evaluate elderly patients for Dr. Nirmal Patel (right) million people over 60 with age-re- management of elderly patients pre- ined the impact of correcting ARHL hearing loss and cognitive function Clinical Associate Professor, Kolling Deafness lated hearing loss by 2050.3 senting with hearing loss. In addition, on cognition. While the data is not yet and refer for appropriate Centre, Macquarie University and University of Age-related hearing loss (ARHL) it aims to raise awareness among GPs definitive, studies have optimistically management. Sydney, Sydney, NSW. is the most common cause of hearing of the strong association between hear- demonstrated that treating ARHL can loss in the elderly and typically begins ing loss and incident dementia within have positive effects on global cogni- HISTORY its onset in the sixth decade of life. the elderly population. The types of tive function, with treated patients PERFORM a focused otologic his- Men tend to have earlier onset and hearing loss are outlined in table 1. frequently improving on cognitive tory and examination in patients pre- greater severity when compared with testing.8,9 This has been shown in senting with a primary complaint of women.4 ARHL can impair the ability ASSOCIATION WITH those with traditional hearing aids as hearing difficulty. Quantify the dura- Copyright © 2020 Australian Doctor Group to effectively communicate and makes DEMENTIA well as cochlear implants.9,10 tion and severity of the hearing loss. All rights reserved. No part of this publication it particularly difficult to hear clearly UNTREATED hearing loss is becoming The benefit, however, seems to be Patients are often accompanied by may be reproduced, distributed, or transmitted in in the presence of competing back- increasing recognised as a contributor limited only to those with mild cogni- family members or caregivers who any form or by any means without the prior writ- ten permission of the publisher. For permission ground noise. Studies have demon- to and exacerbating factor for demen- tive impairment. Studies examining can provide supplemental history requests, email: [email protected] strated reduced quality of life in those tia. The association between dementia the effect of hearing rehabilitation on regarding the impact of hearing loss. 16 HOW TO TREAT: HEARING LOSS IN THE ELDERLY 1 MAY 2020 ausdoc.com.au Ask about other otologic symp- Table 2. Audiometry thresholds toms (see box 1). Accompanying tin- nitus is very common. Aural fullness or pressure and otorrhea may point to Severity Threshold the possibility of infection or chole- steatoma.True vertiginous symptoms Normal <25dB with concomitant hearing loss may point to etiologies such as Meniere’s Mild 26-40dB disease, labyrinthitis, or perilymph Moderate 41-55dB fistula. Assess the risk factors for hearing Moderate-severe 56-70dB loss. These include the accumulation Severe 71-90dB of loud noise exposure over one’s life- MICHAEL HAWKE MD/CC BY-SA 4/BIT.LY/2TSJ5YK BY-SA MD/CC HAWKE MICHAEL time, occupational exposures, use of Profound >90dB hearing protection, history of otologic 13 trauma, or head trauma. Ask about Source: Ahsan S et al 2014 a family history of hearing loss. Per- form a medication review to evaluate for possible ototoxic exposure (see Box 1. Other otologic symptoms box 2, list is not exhaustive). The functional impact of hearing • Difficulty hearing — especially in loss is critical, as it relates to the daily competing noise environment experience of the patient. Patients typ- • Tinnitus — can be mild to ically complain of increasing difficulty debilitating hearing, especially when competing • Aural fullness — sensation background noise is present. There- that the ears are ‘blocked’, or fore, seemingly normal hearing in a ‘underwater’ one-on-one quiet clinic setting should • Otorrhoea not automatically reassure the GP of • Vertigo — efforts should normal hearing function. be made to differentiate Hearing loss is also almost ubiqui- ‘lightheadedness/dizziness’ tously associated with some degree of (non-otologic) from true subjective tinnitus. Tinnitus associ- rotatory vertigo (otologic) ated with hearing loss can occasionally be significantly debilitating and can be severe enough to cause depression and Box 2. Common ototoxic even suicidal ideation. Refer patients medications Figure 1. Perforated tympanic membrane. who complain of pulsatile tinnitus or pulse-synchronous tinnitus for evalua- • Platinum-based tion of possible organic pathology. Table 1. Types of hearing loss recognition testing suggests a retro- chemotherapeutic agents cochlear lesion or significant cochlear — Cisplatin, carboplatin EXAMINATION Category Features Audiometry loss. In these patients, speech per- • Aminoglycosides PERFORM an otoscopic examination — Gentamicin, streptomycin, Conductive Pathologies which impair transmission On audiometry, there is formance will not improve despite tobramycin, amikacin in a stepwise fashion. Abnormalities in hearing loss of sound from the outer and middle a gap between the air increasing the volume. the pinna may suggest congenital (CHL) ear into the inner ear are classified and bone conduction A third type of speech test is the • Other antibiotics anomalies within the middle and as conductive causes of hearing loss. curves, termed the air- hearing-in-noise test (HINT). As the — V ancomycin, chloramphenicol, inner ear. Inspect the external audi- Examples include cerumen impaction, bone gap, or ABG name suggests, the patient is chal- erythromycin tory canal (EAC) for abnormalities — tympanic membrane (TM) perforation lenged with a sentence presented • Loop diuretics excessive cerumen, exostoses, (see figure 1), otosclerosis, otitis with varying loudness of background — Furosemide evidence of trauma, or otitis externa. media, and ossicular chain pathology noise. This data is useful to evaluate Pay special attention to the status of Sensorineural SNHL occurs when, in the absence of On audiometry, the air binaural hearing function. HINT is the tympanic membrane (TM) and hearing loss conductive pathology, the inner ear and bone conduction commonly used as a criteria test for Box 3. Otoscopic examination middle