Presbycusis: A Coordinated and Personalized Approach According to Different Frailty Phenotypes

Abstract

Age-related hearing loss (ARHL) is the most common sensory impairment. Older people with ARHL may vary in their profiles and usually manifest heterogeneous phenotypes, including in combination with presbyastasis, tinnitus, different frailty phenotypes, and multi-morbidity. Patients with these phenotypes generally have a decreased intrinsic capacity, high health burden, and poor prognosis, such as disability, fall, and other adverse events. However, the absence of an evidence-based guidance leads to a significant limitation of current approaches to ARHL care. Here, we present a framework for the rapid and in-depth geriatric assessment, and a recommendation for the coordinated and personalized management of older adults according to their etiology of hearing loss, imbalance, tinnitus, the status of frailty phenotype, and multi-morbidity. The main purpose is to recover functional health, reduce complications, and improve the quality of life for older people with ARHL and frailty phenotypes.

1. Introduction

Age-related hearing loss (ARHL), or presbycusis, is highly prevalent in old age with the increase in life expectancy. It is estimated that 20–26% of adults aged 45 years and increasing to 63% in adults older than 70 years, and nearly 80% of people over 85 years have hearing loss [1, 2, 3]. ARHL is characterized by central auditory processing deficit (CAPD), including temporal processing and frequency resolution, and greater auditory speech perception challenges, apart from different degrees of peripheral hearing loss [4], and often associated with presbyastasis, subjective tinnitus or hyperacusis, and physical, cognitive, and psychological disorders [5, 6, 7, 8]. The interaction of aging and internal and external environment factors results in different pathological alterations and heterogeneous clinical phenotypes. Aging causes gradually increasing decline of multi-system physiological reserve [7]. Some external environmental factors, such as environmental enrichment, including educational, occupational, or leisure activities, are beneficial for the improvement of cognitive and auditory reserves, and active physical exercise for the improvement of multi-system physiological reserves. More environmental factors are harmful for health, referred as to stressors, including physical, physiological, psychosocial, and unhealthy lifestyles [7]. Local audiogenic stressors and otological diseases can cause auditory reserve decline, the imbalance of auditory system homeostasis, and hearing loss with tinnitus. Chronic physiological (functional reserve decline in metabolically active organs, polypharmacy) and psychological stresses (sleep problems and noise exposure), and unhealthy lifestyles (unhealthy diet, smoking, physical inactivity) might lead to the allostatic load and maladaptation in different physiological systems or organs, and multi-morbidities, such as cognitive impairment, cancer, cardiometabolic and affective disorders. In turn, the comorbidities can cause secondary hearing loss, presbyastasis, and tinnitus.

The age-related decline of functional reserve in multiple physiological systems, and following vulnerability increase of the body to minor stressor exposures, might cause the imbalance of homeostasis, allostatic load, and multi-system dysregulation. This condition is defined as frailty that could increase susceptibility to the occurrence of adverse consequences, such as disability, falls, dependence, and death risk [9]. Frailty could be classified into physical [9], cognitive [10], social [11], psychological [12], psychosocial [13], and nutritional [14] frailty phenotypes. Physical frailty rises with age and the prevalence greatly varies because of lack of standardization of concepts or measures. The prevalence of physical frailty is 8–15% in community-dwelling older people and is higher in women than in men [15, 16]. Our community population study (aged 60 years or older) indicated that the prevalence of pre-physical and physical frailty is 35.86 and 4.41% assessed by the FRAIL scale, respectively, and reversible and potential reversible cognitive frailty is 19.86 and 6.3% [17]. The prevalence of (pre-) physical frailty in otological outpatient is 25.5%, cognitive frailty is 32.17%, and cognitive impairment is 18.2% (pre-MCI 10% and MCI 8.2%) [18]. Moreover, patients with physical frailty had a lower risk for severe ARHL, tinnitus, and the presence of ARHL with tinnitus than those with cognitive frailty or cognitive impairment. Patients with the reversible cognitive frailty subtype had a lower risk for severe ARHL, tinnitus, and the presentation of ARHL with tinnitus than those with the potential reversible cognitive frailty subtype. ARHL severity was independently associated with overall cognition, and domain-specific cognition, including executive function, delayed memory, and language function [19]. Patients with ARHL, presbyastasis, and tinnitus had a high risk for cognitive impairment. Physical frailty and ARHL accompanying presbyastasis and/or tinnitus had significant impacts on the overall and domain-specific quality of life [20, 21]. Physical frailty had a stronger and more profound effect on the quality of life, particularly on independent living and pain in the physical dimension and happiness and coping in the psychosocial dimension.

Since ARHL is heterogeneous and usually accompanies high prevalent multi-morbidities, frailty phenotypes, the cooperation among audiologist, otologist, and geriatrician is required to face the aforementioned challenges. Frailty is a pre-disable status, and dynamic and potentially reversible. Apart from hearing and balance rehabilitation, to integrate person-centered geriatric assessment and personalized intervention into the diagnosis and management of ARHL could achieve healthy aging and reduce the risk of complications and adverse outcomes, including geriatric syndrome, functional disability, fall, dependence, and poor quality of life.

2. Early detection of presbycusis with different frailty phenotypes

There are guidelines for the etiological assessment of bilateral sensorineural hearing loss and comprehensive audiological management in children [22, 23]; and for the screening and management of ototoxic hearing loss [24]. There are also some protocols or proposals for the etiological assessment and management of presbyastasis [8, 21, 25] and tinnitus [26, 27]. Moreover, the United States Preventive Services Task Force concluded that the evidence is insufficient to assess the balance of benefits and harms for health outcomes of screening for hearing loss in asymptomatic adults 50 years or older (excluding conductive hearing loss, congenital hearing loss, sudden hearing loss, or hearing loss caused by recent noise exposure, or those reporting signs and symptoms of hearing loss) [28]. However, the international guideline for the screening and management of older adults with ARHL is limited. Notwithstanding, hearing loss has been considered as a critical component of sensory domain impairment of intrinsic capacity (IC) [29]. World Health Organization (WHO) proposed the guidance for the person-centered assessment of intrinsic capacity [30] and for systems and services of integrated care for older people (ICOPE) implementation framework [31]. For older people, several clinical practice guidelines for the screening, assessment, and management of frailty had been proposed by different organizations [32, 33, 34]. In order to reorient the disease-centered to function-centered care model and achieve healthy aging, we propose a coordinated care framework to optimize the early detection and management of ARHL according to the framework for integrated care for older people with intrinsic capacity decline and clinical practice guidelines for the management of frailty.

2.1. Rapid screening for the subject with presbycusis and different phenotypes in primary care

To capture the major clinical events, including declines in functions, onset of disability, frailty, and burdensome chronic diseases in older people aged 60 years and over, a general assessment approach for the subject with ARHL and different frailty phenotypes contains two steps outlined in Figure 1. The recommended step 1 is the rapid geriatric assessment, including rapid screening in primary care settings for the loss in IC and physical frailty phenotypes. Step 2 is the in-depth geriatric assessment in secondary care settings, including frailty phenotypes and the etiology of hearing loss, presbyastasis, and tinnitus.

Figure 1.

An approach to rapid screening and in-depth assessment of ARHL with presbyastasis, tinnitus, frailty phenotypes, and multi-morbidity.

For the beginning, the ICOPE step one is used to screen for loss of domain-specific IC (i.e., locomotion, cognition, vitality/nutrition, and psychological and sensorial capacities) by using a screening test (Table 1) [33, 35]. The screening test can be delivered by primary providers or by patient self-assessment using either a mobile application for a smartphone or an Internet conversational robot. The IC domains were monitored by a primary provider or nurse each 4 months [36].

Intrinsic capacity domains	Recommended screening tests
Cognitive decline	Remember three words: for example: flower, door, rice Orientation in time and space, what is the full date today? Where are you now (home, clinic, etc.) Recalls the three words
Limited mobility	Chair rise test, Rise from chair five times without using arms Did the person complete five chair rises within 14 seconds?
Malnutrition (vitality impairment)	Weight loss: Have you unintentionally lost more than 3 kg over the last 3 months? Appetite loss: Have you experienced loss of appetite?
Depressive systems (impairment in psychological domain)	Over the past 2 weeks, have you been bothered by: feeling down, depressed or hopeless: little interest or pleasure in doing things.
Visual impairment (sensory impairment)	Do you have any problems you are your eyes: difficulties in seeing far, reading, eye diseases or currently under medical treatment (e.g., diabetes, high blood pressure)?
Hearing loss (sensory impairment)	Hears whispers (whisper test) or screening audiometry result is 35 dB or less or passes automated app-based digits-in-noise test

Table 1.

The rapid screening for the loss in intrinsic capacity [33, 35].

About sensorial capacity domain, we proposed a preliminary presbyastasis and tinnitus screening also should be performed during hearing loss screening, since presbyastasis and tinnitus are the most related symptoms in older adults with hearing loss. Presbyastasis, or age-related degeneration of peripheral as well as the central part of the vestibular system, refers to dizziness and/or ataxia with apparent localizing signs and is typically attributed to the aging process [25, 37]. The clinical differentiation of presbyastasis from symptoms related to specific diseases or risk factors is required based on medical history. These diseases include specific or unilateral vestibular diseases, such as Meniere’s disease, visional impairment from various etiologies, muscle weakness, neurological lesions, diabetes-related neuropathy, cognitive impairment, arthritis, narrowing of the lumbar vertebral canal, and lumbago-sciatica [21, 25, 38]. The risk factors include polypharmacy, especially drugs for hypertension (e.g., diuretics), anxiety, or depression, excessive consumption of alcohol, and extrinsic environmental factors, such as stairs and other indoor obstacles [25]. ARHL and noise exposure are the most common causes of non-pulsatile tinnitus (subjective tinnitus) [5, 6]. Other etiologically differential diagnosis of tinnitus symptoms includes pulsatile or objective (pulsatile synchronous or vascular and asynchronous or mechanical) tinnitus, and more common subjective tinnitus accompanying unilateral or bilateral hearing loss [26, 27]. The screening also includes tinnitus-related systemic morbidities, such as cardiometabolic diseases, mental health disorders, neurological diseases (e.g., multiple sclerosis and head injury), tinnitus-related otological diseases, such as Meniere’s disease, middle ear infection, noise exposure, and tinnitus-related polypharmacy, such as diuretics for hypertension therapy [39], aspirin [40, 41], and other ototoxic medications [24]. Visual analog scales and questionnaires (e.g., Tinnitus handicap inventory and Tinnitus functional index) usually are used to assess tinnitus annoyance, distress, and severity [42].

Once IC decline was confirmed, individuals would have rapid physical frailty screening [33]. Although there are more than a dozen rapid frailty screening instruments, the FRAIL Scale is widely validated, simple, and rapid tool for the screening of physical frailty phenotype [32, 33, 34]. The FRAIL scale is a simple five-item questionnaire: Fatigue: Are you fatigued? Resistance: Cannot walk up one flight of stairs? Aerobic: Cannot walk one block? Illnesses: Do you have more than five illnesses? Loss of weight: Have you lost more than 5% of your weight in the last 6 months? Pre-physical frailty is defined as scoring 1 or 2; physical frailty is defined as scoring 3 or greater.

After IC and physical frailty screening, individuals were classified into with (pre-) physical frailty and without frailty. Among these with (pre-) physical frailty, individuals further were classified into psychological, nutritional, cognitive, and mixed frailty phenotypes according to the decline of domain-specific IC. The mixed frailty phenotype means accompanying a decline in two or more than two domains of IC. Individuals with cognitive frailty could be classified into reversible and potential reversible cognitive frailty [10, 17] using the rapid cognitive screening (RCS) tool [43] in combination with a pre-mild cognitive impairment (pre-MCI) questionnaire with two items [17]. The scores for dementia and MCI were ≤5 and 6-7, respectively. Individual with a score of 8-10 was considered to have pre-MCI when had a positive response to pre-MCI questionnaire. Individuals with (pre-) physical frailty and pre-MCI or MCI were defined as reversible or potentially reversible cognitive frailty.

Individuals without (pre-) physical frailty but with domain-specific decline of IC were referred to as psychological, cognitive, and sensory diseases, and other multi-morbidities (less than five chronic illnesses in the FRAIL questionnaire). These without domain-specific decline of IC and chronic diseases were considered as robust individuals. Thus, older people were classified into individuals having ARHL with different frailty phenotypes and multi-morbidity, individuals having ARHL with multi-morbidities (especially cardiometabolic morbidity), these with different frailty phenotypes, and robust individuals.

2.2. In-depth Assessment for the subject with presbycusis and different phenotypes in secondary care

Although rapid screening instruments for frailty phenotypes are sensitive, these tools often display low specificity [44]. In order to timely identify the causes of ARHL and tinnitus, individuals with ARHL and different frailty phenotypes by rapid geriatric assessment require referral to secondary care for in-depth IC-centered geriatric evaluation and frailty phenotype assessment by audiologist/geriatrician. The ICOPE care plan provides preliminary recommendations for in-depth geriatric assessment for the loss of IC [35].

Since individuals with ARHL usually accompany CAPD, presbyastasis, and subjective tinnitus, we proposed additional tests for the in-depth assessment of ARHL. For peripheral ARHL in-depth assessment, the results of audiometry should include pure-tone threshold average of the frequencies 0.5, 1.0, and 2.0 kHz (speech-frequency pure-tone average) and 4.0, 6.0, and 8.0 kHz (high-frequency pure-tone average). The word recognition (discrimination) scoring was determined by using the percentage of recognition of a list of monosyllabic phonetically balanced words at 30–40 dB above the PTA threshold for each ear. A score greater than 70% was considered normal to understand speech in a quiet environment [45, 46]. According to the WHO definition of disabling ARHL, peripheral ARHL was defined as a PTA threshold greater than 40 dB hearing level in the better ear [47].

For CAPD in-depth assessment, the eligible subject criteria for the central auditory tests include normal tympanogram, presenting ipsilateral acoustic reflexes, no history of ear surgery to exclude possible middle ear disease in the past or present, no history of hearing loss since childhood, and less than 21 dB difference among pure-tone averages (PTA) for 0.5, 1.0, and 2.0 kHz for the two ears to exclude otologic disorders (e.g., congenital or unilateral sudden deafness, tumor, or infection) other than aging [45, 46]. Moreover, individuals have no disabling peripheral ARHL (i.e., PTA threshold below 40 dB hearing level in the better ear, word recognition score at 30 dB over PTA threshold over 70%) [45, 46]. The test used to diagnose age-related CAPD includes the Synthetic Sentence Identification With Ipsilateral Competitive Message (SSI-ICM), Staggered Spondaic Word test, and other tests [48]. The SSI-ICM test consists of administering for each ear a primary signal of 10 short sentences against a background competition signal. The short sentences are presented at 50 dB over the PTA for each ear. The rate of identification of sentences is expressed as a percentage (0–100%) at various primary-competitive ratios (0, +5, +10 dB sound pressure level). Age-related CAPD was considered present when the patient scored less than 50% in the better ear with a 0-dB message-competition ratio [45, 46, 48].

Apart from medical history, the in-depth assessment for individuals with presbyastasis includes gait and stance assessment, such as “time up-and-go” test, standing on one leg, to differentiate dizziness from ataxia [25]. Hearing assessment, other accurate otoneurological evaluation, including Romberg, Unterberger, head-shaking, and Halmagyi tests, the Dix-Hallpike maneuver, and dynamic posturography; vestibular function assessment tests, such as rotational and caloric tests, videonystagmography or electronystagmography examination, and otolith function assessment usually were used to differentiate presbyastasis from disease-specific imbalance. [8, 25]. The video head impulse test was recently verified to be an effective test for the differentiation presbyastasis from Meniere’s disease [38] and the prediction of fall risk in elderly patients [21]. Computed tomography imaging, MRI scanning, and ultrasonography are important auxiliary examinations.

The in-depth assessment for referring people with tinnitus includes tinnitus with acute conditions, such as a crisis of mental health, significant neurological systems or signs, uncontrolled vestibular symptoms, suspected stroke [49], tinnitus disorder (associated with emotional distress, cognitive dysfunction, and/or autonomic arousal, leading to behavioral changes, and functional disability) [50], tinnitus with sudden hearing loss, objective tinnitus, and tinnitus with unilateral or asymmetric hearing loss [26, 27, 49]. The differential diagnosis of tinnitus symptoms could be conducted by in-depth assessment, including audiological testing, psychoacoustic tests (pitch, loudness, and matching), and imaging. Idiopathic intracranial hypertension, glomus tumors, and atherosclerosis of the carotid arteries are frequent causes of pulse synchronous tinnitus [51]. Eustachian tube contraction and middle ear muscle myoclonus might cause pulse asynchronous tinnitus [27]. Unilateral tinnitus, but normal otoscopy and positive neurologic signs might be caused by cerebellopontine angle tumor, brainstem infarction, and multiple sclerosis; and by noise exposure; and these with negative neurologic signs might be Meniere’s disease, semicircular canal dehiscence. Apart from ARHL and noise exposure, bilateral hearing loss and normal otoscopy findings might also be caused by acoustic trauma, otosclerosis, and ototoxic medication [26, 27].

To improve the specificity of (pre-) physical frailty, a cardiovascular health study frailty screening scale with more objective parameters (weight loss, exhaustion, low activity, slowness, and weakness) is used as an in-depth assessment instrument [9]. Individuals with a score of 1 or 2 is diagnosed as pre-physical frailty; and with a score of 3 or greater is diagnosed as physical frailty. Individuals, with (pre-) physical frailty simultaneously presenting impairment in the cognitive domain of IC, are classified as cognitive frailty. Cognitive performance could be thoroughly assessed by using demographically corrected normative z scores on the Neuropsychological Test Battery [52, 53, 54]. Reversible and potentially reversible cognitive frailty subtypes could be diagnosed according to the severity of cognitive impairment, including pre-MCI and MCI [18]. Social and psychological domains of IC are assessed by using the 21-item Social Dysfunction Rating Scale [55] and the 15-item short form of the Geriatric Depression Scale [56], respectively. Individuals with (pre-) physical frailty simultaneously presenting social or psychological dysfunction are classified as social or psychological frailty phenotype. Nutritional frailty phenotype could be diagnosed when individuals simultaneously present (pre-) physical frailty and nutritional imbalance [14]. Malnutrition also could be identified using a Mini nutritional assessment or malnutrition universal screening tool [35]. These in-depth geriatric assessments may uncover unrecognized problems following the rapid geriatric screening and provides the possibility for multi-disciplinary specialists to design and implement function-centered and personalized interventions, which can promote patient healthy aging.

3. The management of presbycusis with different frailty phenotypes

Multi-modality intervention is required for these ARHL with frailty phenotypes and/or multi-morbidity. An integrated and person-centered approach to the management of ARHL with frailty phenotypes and multi-morbidity is shown in Table 2.

Hearing loss	Presbyastasis	Tinnitus	Frailty phenotypes	Multi-morbidity
Stop noise and ototoxic medication exposure	Identify risk factors and exclude potential curable causes	Exclude polypharmacy-related subjective tinnitus	Multi-component physical activity programs (resistance and aerobic exercise, balance, or coordination training) to reverse or slow the progression of (pre-)physical frailty	Proactive personalized assessment and care plan
Prescribe hearing aid	Vestibular and balance rehabilitation	Optimal pre-operative risk and toxicity assessment of invasive therapies and thorough monitoring during the treatment period to these with tinnitus of definite cause	Adequate protein, energy, and micronutrient supplementation to these with malnutrition	Optimizing the management of multi-morbidity
Optimal pre-operative risk assessment and thorough monitoring during the treatment period to these considering cochlear implant for severe-to-profound sensorineural hearing loss with poor word recognization	Drug treatment (e.g., betahistine) to increase cerebral blood flow; Other vasodilator and antivertiginous drugs	Subjective tinnitus intervention: amplification, sound, and neuromodulation	Optimizing environment and the improvement of health behavior	Reduction of polypharmacy
Optimal pre-operative risk and toxicity assessment of other invasive therapies and thorough monitoring during the treatment period to these with hearing loss of definite cause	Fall prevention, including regular physical and intellectual activities, nutritional supplement	Cognitive behavioral or comprehensive therapy to these with tinnitus disorder	Optimizing psychosocial resources to these with low mood and affective problems	Reduction of treatment burden, adverse event, and uncoordinated care
			Cognitive behavior training to these with cognitive decline

Table 2.

The coordinated and personalized management of hearing loss with frailty phenotypes and multi-morbidity.

3.1. Non-invasive treatment of ARHL with different frailty phenotypes

The integrated and person-centered management includes ARHL, presbyastasis, tinnitus, frailty phenotypes, and multi-morbidity. The primary management is to improve unfavorable lifestyles, including smoking, alcohol consumption, physical inactivity, improper nutrition, and poor social, economical, and environmental conditions, and reduction of polypharmacy, including the number and the dosage, and these increase the risk for presbyastasis, delirium, cardiovascular disease, kidney, and ototoxicity. The non-invasive intervention for ARHL is to prescribe a hearing aid, which could significantly slow short- and long-term cognitive decline [57]. The management of presbyastasis includes the identification of risk factors and potentially curable causes, vestibular and balance rehabilitation, and drug treatment, such as H1-receptor agonist and H3-receptor anti-agonist (e.g., betahistine) and Other vasodilator and antivertiginous drugs, and fall prevention, including regular physical and intellectual activities with gradually increasing difficulty and nutritional supplement [25, 37]. Amplification by hearing aids acting as a masker by introducing more ambient noise also is used to relieve subjective tinnitus symptoms in some patients. Other non-invasive subjective tinnitus interventions include sound therapy, psychological therapies, neuromodulation, and combined therapy of these interventions [26, 27, 49, 58]. Psychological therapies, such as cognitive behavioral therapy, have been shown to improve quality of life and decrease depression for these with persistent and bothersome tinnitus, or tinnitus disorder [24, 59].

The interventions recommended by different international organizations to reverse or slow the progression of frailty include multi-component physical activity programs, adequate nutrition supplementation, and cognitive behavior training to improve physiological, psychological, and cognitive reserves [31, 32, 33, 34, 60]. The decline of physiological, psychological, and cognitive reserves also causes multi-morbidity, and the complex overlap of frailty and morbidity, physical and mental health disorders, and frailty and polypharmacy [61]. The management of multi-morbidity includes a proactive personalized assessment and care plan, which improves the quality of life by reducing treatment burden, adverse events, and unplanned or uncoordinated care [61]. Recently, the holistic and patient-centered hearing healthcare had been proposed, including the integrated management of hearing loss with diabetes, dementia, and other comorbidities [62].

3.2. Invasive treatment in ARHL with different frailty phenotypes

Invasive treatment includes surgery, radiotherapy, chemotherapy, and multi-modal therapy. Individuals with ARHL and different frailty phenotypes may need a cochlear implant due to severe-to-profound sensorineural hearing loss with poor word recognition. Geriatric patients with dizziness-related specific diseases, or objective tinnitus-related diseases, such as idiopathic intracranial hypertension, vascular tumors, and these with subjective tinnitus-related diseases, including Meniere’s disease, cholesteatoma, and otosclerosis, require complex surgery, and tinnitus-related Cerebellopontine angle tumor, acoustic neuroma, and skull base tumors require multi-modal therapy. Compared with younger patients, older people have higher surgery risk and radio- and chemotherapy toxicity. The prevalence of physical frailty in geriatric patients for elective surgery is over 10%, and individuals with physical frailty have more than two times higher risk of postoperative complications [63]. The frequent postoperative complications include death, delirium, extending stay in hospital, falls, functional deterioration, and poorer quality of life, apart from complications resulting from existing diseases such as acute coronary syndromes, stroke, thromboembolism, pneumonia, or other infections. Multi-morbidity and functional limitations are also indicated to be the main predictors of adverse prognosis and poorer tolerance of multi-modality therapy in geriatric patients with head and neck cancer [64]. However, direct evidence of adverse prognosis of the above treatments for ARHL and tinnitus with frailty phenotypes is absent. Cochlear implantation had been validated to slow cognitive decline and the progression of dementia [57, 65]. A previous study indicated that cochlear implant for older patients with frailty does not cause additional complications from existing diseases [66].

To balance the risk and benefit, the cooperation between an otolaryngologist and a geriatrician had been recommended to identify these high-risk patients and optimize the treatment with special surveillance during the treatment period [67]. A guideline for pre-operative assessment of geriatric patients had been proposed that comprehensive geriatric assessment, such as physical and mental health, daily and social function, frailty, and poly-pharmacotherapy, should be implemented during the diagnostic and therapeutic, and post-operative process [68]. The guideline is similar to our in-depth assessment of IC and frailty phenotypes. Identification of deficits in IC and frailty phenotype, and multi-morbidity in pre-operative assessment not only are used to make surgical decisions, and choose anesthesia techniques, peri-operative care, and nursing plans to minimize complications, but also allow for the patient’s pre-operative preparation through nutritional support, functional improvement, and rehabilitation, and excluding surgical contraindications.

4. To prevent secondary presbycusis in subjects with different frailty phenotypes

Individuals with frailty phenotypes, or more complex overlap of frailty, multi-morbidity, and polypharmacy, usually showed an imbalance of homeostasis to additional minor stressors. The long-term allostatic load results in dysfunction in the neuroendocrine-immune system and metabolism (Figure 2). The maladaptation of these regulation systems results in the decline of stress-responsive capacity of the HPA axis and autonomic nervous system, chronic systemic inflammation, and over mobilization of energy metabolism. All these systemic alterations might cause secondary ARHL, tinnitus, and other widespread functional impairment or health deficits [7].

Figure 2.

The secondary ARHL with presbyastasis and/or tinnitus in subjects with frailty phenotypes and multi-morbidity.

To improve IC capacity and decrease stress exposure are the basic principles for the management of these individuals. Multi-component physical activity programs, nutrition supplementation, and environmental enrichment can enhance the physical, cognitive [69], and auditory reserves [70]. The management of multi-morbidity and polypharmacy, optimal home, and psychosocial environment could slow the progress from frailty to disability, including secondary ARHL [32, 33, 34, 60].

5. Challenges of the detection and management of presbycusis with different frailty phenotypes

There are several critical challenges to optimize the diagnosis and management of presbycusis with different frailty phenotypes. One of the main challenges is frailty construct and screening instruments for clinical practice. Two well-validated and the most widely used models in clinical practice are variations of the frailty phenotype or frailty indexes based on the deficit accumulation approach [9]. However, most instruments lack extensive validation. Simple, rapid instruments for the assessment of frailty phenotypes based on physical frailty seem to meet the clinical translation demands. The evidence for frailty phenotypes, such as social frailty, nutritional frailty, and cognitive frailty, and subtypes, such as reversible and potential reversible cognitive frailty, is still limited.

Another main challenge is two parallel constructs with the same mission for healthy aging: IC and multi-morbidity. IC is endorsed by WHO but still lacks an operational definition, especially in the vitality domain [71]. Since many instruments are commonly used to diagnose frailty phenotypes and IC, it is necessary to integrate the two constructs and reduce confusion in clinical practice. Although frailty and multi-morbidity are different concepts, more than 16% of people have multi-morbidity with frailty and about three-quarters of people have frailty with multi-morbidity [72], it is difficult to separate different frailty phenotypes from comorbidities, such as cognitive frailty vs. cognitive impairment, and psychological frailty vs. psychological diseases.

There are similar challenges to differentiate peripheral from central ARHL, and tinnitus disorder from tinnitus with frailty phenotypes and multi-morbidity, especially with cognitive frailty or impairment, and psychological frailty or disorders. Therefore, further research is imperative to provide a more evidence-based proposal to improve the coordinated and personalized care to these with complex geriatric conditions.

6. Conclusions

The bidirectional association between ARHL and frailty phenotypes and multi-morbidity supports coordinated and personalized care for older people with ARHL and different frailty phenotypes. We proposed the rapid screening, in-depth assessment of IC, and frailty phenotypes as part of routine ARHL management. Albeit based predominantly on consensus and recommendation, we hope coordinated and personalized treatment strategies could be employed to reduce the complication and improve health and quality of life.

Acknowledgments

This work was supported by the Huadong Hospital project on intractable and complicated diseases (grant no. 20220101), the Medical Science and Technology Support Project of Shanghai Science, Technology Commission (grant No. 18411962200).

Conflict of interest

The authors declare no conflict of interest.