Duration of Analgesic Use and Risk of Hearing Loss in Women

Establishing multifactorial risk factors for adult-onset hearing loss: A systematic review with topic modelling and synthesis of epidemiological evidence

BACKGROUND

This systematic review explores the multifaceted nature of risk factors contributing to adult-onset HL. The objective was to synthesise the most recent epidemiological evidence to generate pooled proportional incidences for the identified risk factors.

METHODS

We conducted an extensive search of electronic databases (MEDLINE, EMBASE, and psychINFO) for studies providing epidemiological evidence of risk factors associated with hearing loss. Topic modelling using Latent Dirichlet Allocation (LDA) was first conducted to determine how many risk factor themes were available from the papers. Data were analysed by calculating the pooled proportional incidence using a meta-analysis of proportions.

RESULTS

From the 72 studies reviewed, six key risk factor themes emerged through LDA topic modelling. The review identified ototoxicity, primarily caused by cancer treatments and antibiotics, infectious diseases like COVID-19, occupational noise exposure, lifestyle factors, health conditions, biological responses, and age progression as significant risk factors for HL. The highest proportional incidence was found with cancer-related ototoxicity at 55.4% (95%CI: 39.0-70.7), followed closely by ototoxicity from infectious diseases at 50.0% (95%CI: 28.5-71.5). This high proportional incidence suggests the need to explore less destructive therapies and proactively monitor hearing function during treatments.

CONCLUSIONS

The findings of this review, combined with the synthesis of epidemiological evidence, enhance our understanding of hearing loss (HL) pathogenesis and highlight potential areas for intervention, thereby paving the way for more effective prevention and management of adult-onset hearing loss in our ageing global population.

The Effects of Substance Misuse on Auditory and Vestibular Function: A Systematic Review

BACKGROUND

Chronic substance misuse is an ongoing and significant public health concern. Among a myriad of health complications that can occur, substance misuse potentially causes ototoxic effects. Case reports, retrospective chart data, and a few cohort studies suggest that certain prescription opioids and illicit drugs can have either temporary or permanent effects on auditory and/or vestibular function. Given the steady rise of people with a substance-use disorder (SUD), it is of growing importance that audiologists and otolaryngologists have an insight into the potential ototoxic effects of substance misuse.

OBJECTIVES

A systematic review was conducted to (1) synthesize the literature on the illicit drugs, prescription opioids, and alcohol misuse on the auditory and vestibular systems, (2) highlight common hearing and vestibular impairments for each substance class, and (3) discuss the limitations of the literature, the potential mechanisms, and clinical implications for clinicians who may encounter patients with hearing or vestibular loss related to substance misuse, and describe opportunities for further study.

DESIGN

Systematic searches were performed via PubMed, Scopus, and Google Scholar, and the final updated search was conducted through March 30, 2022. Inclusion criteria included peer-reviewed articles, regardless of study design, from inception until the present that included adults with chronic substance misuse and hearing and/or vestibular complaints. Articles that focused on the acute effects of substances in healthy people, ototoxicity from already known ototoxic medications, the relationship between hearing loss and development of a SUD, articles not available in English, animal work, and duplicates were excluded. Information on the population (adults), outcomes (hearing and/or vestibular data results), and study design (e.g., case report, cohort) were extracted. A meta-analysis could not be performed because more than 60% of the studies were single-case reports or small cohort.

RESULTS

The full text of 67 studies that met the eligibility criteria were selected for the review. Overall, 21 studies reported associations between HL/VL related to illicit drug misuse, 28 studies reported HL/VL from prescription opioids, and 20 studies reported HL/VL related to chronic alcohol misuse (2 studies spanned more than one category). Synthesis of the findings suggested that the misuse and/or overdose of amphetamines and cocaine was associated with sudden, bilateral, and temporary HL, whereas HL from the combination of a stimulant and an opioid often presented with greater HL in the mid-frequency range. Reports of temporary vertigo or imbalance were mainly associated with illicit drugs. HL associated with misuse of prescription opioids was typically sudden or rapidly progressive, bilateral, moderately severe to profound, and in almost all cases permanent. The misuse of prescription opioids occasionally resulted in peripheral VL, especially when the opioid misuse was long term. Chronic alcohol misuse tended to associate with high-frequency sudden or progressive sensorineural hearing loss, or retrocochlear dysfunction, and a high occurrence of central vestibular dysfunction and imbalance.

CONCLUSIONS

Overall, chronic substance misuse associates with potential ototoxic effects, resulting in temporary or permanent hearing and/or vestibular dysfunction. However, there are notable limitations to the evidence from the extant literature including a lack of objective test measures used to describe hearing or vestibular effects associated with substance misuse, small study sample sizes, reliance on case studies, lack of controlling for confounders related to health, age, sex, and other substance-use factors. Future large-scale studies with prospective study designs are needed to further ascertain the role and risk factors of substance misuse on auditory and vestibular function and to further clinical management practices.

COX inhibitor use during definitive radiotherapy is associated with worse hearing preservation in patients with vestibular schwannoma

PURPOSE

Patients with vestibular schwannoma undergoing definitive radiotherapy commonly experience hearing loss due to tumor and treatment effects; however, there is limited data evaluating concurrent medication use and other clinicopathologic factors associated with hearing preservation during and after radiotherapy. We performed a retrospective cohort study reviewing consecutive patients from 2004 to 2019 treated with radiotherapy for vestibular schwannoma at our institution.

METHODS

Ninety four patients with concurrent medications, baseline audiograms, and post-radiotherapy audiograms available were evaluable. We performed chi-squared analyses of the frequency of various clinicopathologic factors and t-tests evaluating the degree of hearing loss based on audiograms.

RESULTS

At a median follow-up of 35.7 months (mean: 46.5 months), the baseline pure-tone average (PTA) of the ipsilateral ear worsened from 38.4 to 59.5 dB following completion of radiotherapy (difference: 21.1, 95% CI 17.8-24.4 dB, p < 0.001). 36 patients (38.3%) reported regular use of cyclooxygenase (COX) inhibitors (including acetaminophen and NSAIDs) during radiotherapy. The mean increase in PTA was significantly higher for patients taking COX inhibitors (25.8 dB vs 18.1 dB, p = 0.024) in the ipsilateral ear but not for the contralateral side. COX inhibitor use remained independently associated with worse PTA in the multivariate analysis.

CONCLUSION

COX inhibitor use during definitive radiotherapy is associated with worse hearing loss in the affected ear but not for the contralateral side. This suggests the ototoxic effects of COX inhibitors may influence the effects of radiotherapy. These results could have clinical implications and warrant further investigation.

Longitudinal Study of Analgesic Use and Risk of Incident Persistent Tinnitus

BACKGROUND

Persistent tinnitus is common, disabling, and difficult to treat. High-dose aspirin may precipitate tinnitus, but longitudinal data on typical dose aspirin and other analgesics are scarce.

OBJECTIVE

To investigate independent associations of aspirin, NSAIDs, and acetaminophen and risk of incident persistent tinnitus.

DESIGN

Longitudinal cohort study.

SETTING

Nurses' Health Study II (1995-2017).

PARTICIPANTS

A total of 69,455 women, age 31-48 years, without tinnitus at baseline.

MAIN MEASURES

Information on analgesic use and tinnitus obtained by biennial questionnaires.

KEY RESULTS

After 1,120,936 person-years of follow-up, 10,452 cases of incident persistent tinnitus were reported. For low-dose aspirin, the risk of developing persistent tinnitus was not elevated among frequent low-dose aspirin users. For moderate dose aspirin, frequent use was associated with higher risk of tinnitus among women aged < 60 years, but not among older women (p-interactionage = 0.003). Compared with women aged < 60 using moderate-dose aspirin < 1 day/week, the multivariable-adjusted hazard ratio (MVHR, 95% CI) among women using moderate-dose aspirin 6-7 days per week was 1.16 (1.03, 1.32). Among all women, frequent non-aspirin non-steroidal anti-inflammatory drug (NSAID) or acetaminophen use was associated with higher risk. Compared with women using NSAIDs <1 day/week, the MVHR for use 4-5days/week was 1.17 (1.08, 1.28) and for 6-7days/week was 1.07 (1.00, 1.16) (p-trend=0.001). For acetaminophen, compared with use <1 day/week, the MVHR for use 6-7days/week was 1.18 (1.07, 1.29) (p-trend=0.002).

LIMITATIONS

Information on tinnitus and analgesic use was self-reported. Information on indications for analgesic use was not available. Studies in non-White women and men are needed.

CONCLUSION

The risk of developing persistent tinnitus was not elevated among frequent low-dose aspirin users. Among younger women, frequent moderate-dose aspirin use was associated with higher risk. Frequent NSAID use and frequent acetaminophen use were associated with higher risk of incident persistent tinnitus among all women, and the magnitude of the risks tended to be greater with increasing frequency of use. Our results suggest analgesic users are at higher risk for developing tinnitus and may provide insight into the precipitants of this challenging disorder, but additional investigation to determine whether there is a causal association is needed.

Birth Weight and Adult-Onset Hearing Loss

OBJECTIVES

Among low-birth-weight infants, exposure to stress or undernutrition in utero may adversely affect cochlear development. As cochlear reserve declines, the risk of hearing loss may increase with age. While low birth weight is associated with a higher risk of neonatal hearing loss, our objective was to examine whether birth weight was associated with adult-onset, self-reported hearing loss in the Nurses' Health Studies (NHS) I and II (n = 113,130).

DESIGN

We used Cox proportional hazards regression to prospectively examine whether birth weight, as well as gestational age at birth, is associated with adult-onset hearing loss. Participants reported their birth weight in 1992 in NHS I and 1991 in NHS II. Mothers of NHS II participants reported gestational age at birth in a substudy (n = 28,590). The primary outcome was adult-onset, self-reported moderate or greater hearing loss, based on questionnaires administered in 2012/2016 in NHS I and 2009/2013 in NHS II.

RESULTS

Our results suggested a higher risk of hearing loss among those with birth weight <5.5 lbs compared with birth weight 7 to <8.5 lbs (pooled multivariable-adjusted hazard ratio 1.14, 95% confidence interval = 1.04-1.23; p trend = 0.01). Additionally, participants with gestational age at birth ≥42 weeks had a higher risk of hearing loss, compared with gestational age 38 to <42 weeks (multivariable-adjusted hazard ratio 1.33, 95% confidence interval = 1.06-1.65).

CONCLUSIONS

Birth weight <5.5 lbs was independently associated with higher risk of self-reported, adult-onset hearing loss. In addition, gestational age at birth ≥42 weeks was also associated with higher risk.

Cigarette Smoking, Smoking Cessation, and Risk of Hearing Loss in Women

BACKGROUND

Previous studies demonstrated higher risk of hearing loss among cigarette smokers, but longitudinal data on whether the risk is influenced by smoking cessation are limited. We prospectively investigated relations between smoking, smoking cessation, and risk of self-reported moderate or worse hearing loss among 81,505 women in the Nurses' Health Study II (1991-2013).

METHODS

Information on smoking and hearing status was obtained from validated biennial questionnaires. Cox proportional hazards regression was used to estimate multivariable-adjusted relative risks (MVRR, 95% confidence interval).

RESULTS

During 1,533,214 person-years of follow-up, 2760 cases of hearing loss were reported. Smoking was associated with higher risk of hearing loss and the risk tended to be higher with greater number of pack-years smoked. Compared with never smokers, the MVRR (95% confidence interval) among past smokers with 20+ pack-years of smoking was 1.30 (1.09-1.55) and 1.21 (1.02-1.43) for current smokers. The magnitude of elevated risk diminished with greater time since smoking cessation. Compared with never smokers, the MVRR among smokers who quit <5 years prior was 1.43 (1.17-1.75); 5-9 years prior was 1.27 (1.03-1.56); 10-14 years prior was 1.17 (0.96-1.41); and plateaued thereafter. Additional adjustment for pack-years smoking attenuated the results.

CONCLUSIONS

The higher risk of hearing loss associated with smoking may diminish over time after quitting.

The Contribution of Ototoxic Medications to Hearing Loss Among Older Adults

BACKGROUND

Ototoxicity may interact with the effects of aging, leading to a more severe hearing loss than that associated with age alone. The purpose of this study was to explore the associations between ototoxic medication use and the incidence and progression of hearing loss in older adults with a population-based longitudinal study.

METHODS

Epidemiology of Hearing Loss Study participants (n = 3,753) were examined. Medication use was assessed using a standardized questionnaire by the examiners at each examination every 5 year. The ototoxic medications include loop diuretics, nonsteroidal anti-inflammatory drugs, antibiotics, chemotherapeutic agents, quinine, and acetaminophen in this study. Generalized estimating equations model was used as a proportional hazard discrete time analysis.

RESULTS

Number of ototoxic medications was associated with the risk of developing hearing loss during the 10-year follow-up period (hazard ratio [HR] = 1.15, 95% confidence interval [CI] = 1.06, 1.25) after adjusting for age, sex, smoking, and body mass index. Loop diuretics (HR = 1.40, 95% CI = 1.05, 1.87) were associated with the 10-year incidence of hearing loss. Nonsteroidal anti-inflammatory drugs (HR = 1.45, 95% CI = 1.22, 1.72) and loop diuretics (HR = 1.33 95% CI = 1.08, 1.63) were associated with risk of progressive hearing loss over 10 years.

CONCLUSION

These ototoxic medications are commonly used in older adults and should be considered as potentially modifiable contributors to the incidence and severity of age-related hearing loss.

Biomarkers of Systemic Inflammation and Risk of Incident Hearing Loss

BACKGROUND

Chronic inflammation may lead to cochlear damage, and the only longitudinal study that examined biomarkers of systemic inflammation and risk of hearing loss found an association with a single biomarker in individuals <60 years of age. The purpose of our study was to determine whether plasma inflammatory markers are associated with incident hearing loss in two large prospective cohorts, Nurses' Health Studies (NHS) I and II.

METHODS

We examined the independent associations between plasma levels of markers of systemic inflammation (C-reactive protein [CRP], interleukin-6 [IL-6], and soluble tumor necrosis factor receptor 2 [TNFR-2]) and self-reported hearing loss. The participants in NHS I (n = 6194 women) were 42 to 69 years of age at the start of the analysis in 1990, while the participants in NHS II (n = 2885 women) were 32 to 53 years in 1995. After excluding women with self-reported hearing loss before the time of blood-draw, incident cases of hearing loss were defined as those women who reported hearing loss on questionnaires administered in 2012 in NHS I and 2009 or 2013 in NHS II. The primary outcome was hearing loss that was reported as moderate or worse in severity, pooled across the NHS I and NHS II cohorts. We also examined the pooled multivariable-adjusted hazard ratios for mild or worse hearing loss. Cox proportional hazards regression was used to adjust for potential confounders.

RESULTS

At baseline, women ranged from 42 to 69 years of age in NHS I and 32 to 53 years of age in NHS II. Among the NHS I and II women with measured plasma CRP, there were 628 incident cases of moderate or worse hearing loss during 100,277 person-years of follow-up. There was no significant association between the plasma levels of any of the three inflammatory markers and incident moderate or worse hearing loss (multivariable-adjusted pooled p trend for CRP = 0.33; p trend IL-6 = 0.54; p trend TNFR-2 = 0.70). There was also no significant relation between inflammatory marker levels and mild or worse hearing loss. While there was no significant effect modification by age for CRP or IL-6 in NHS I, there was a statistically significant higher risk of moderate or worse hearing loss (p interaction = 0.02) as well as mild or worse hearing loss (p interaction = 0.004) in women ≥60 years of age who had higher plasma TNFR-2 levels.

CONCLUSIONS

Overall, there was no significant association between plasma markers of inflammation and risk of hearing loss.

Expression of drug metabolizing enzymes and transporters in the cochlea: Implications for drug delivery and ototoxicity

Inner ear drug delivery is a major area of research and development, but relatively little is known about basic drug metabolism in the cochlea. Additionally, the use of potentially ototoxic drugs such as NSAIDs, chemotherapeutics and aminoglycosides is common, but little is known about the role of metabolism in ototoxicity of those drugs. To address those issues, we compared expression of major Cytochromes P450 (Cyps), UDP-glucuronosyl-transferases (Ugts), sulfotransferases (Sults), and drug transporters between cochleae and liver, an organ with high expression, in mice using qPCR and enzyme kinetics. Together, the tested drug-metabolizing enzymes (DMEs) and transporters account for metabolism of approximately 70-80% of all medically important drugs in the body. Expression of most Cyps was low in the cochlea compared to liver, but three displayed similar expression levels to the liver, and one (Cyp2c65) had significantly higher levels of expression in the cochlea (1.9 ± 0.06 fold vs. liver). Enzyme kinetics revealed undetectable levels of p450 activity in the cochlea, especially as compared to the liver. Similar results were obtained for expression of Ugts and Sults. Interestingly, expression of most transporters was also low, with one major exception: Mdr1/P-glycoprotein (P-gp), which is generally thought to be highly expressed in liver and poorly expressed in most of the nervous system, was 3-fold greater in cochlea. Importantly, P-gp is known to protect other tissues from toxicity of cancer drugs by acting as an efflux pump. Our data demonstrate overall low levels of expression of DMEs and transporters in the cochlea, and identify a few that may be important to consider when designing and testing drugs for local delivery to the inner ear.

A New Approach to Treating Neurodegenerative Otologic Disorders

Hearing loss, the most common neurological disorder and the fourth leading cause of years lived with disability, can have profound effects on quality of life. The impact of this "invisible disability," with significant consequences, economic and personal, is most substantial in low- and middle-income countries, where >80% of affected people live. Given the importance of hearing for communication, enjoyment, and safety, with up to 500 million affected globally at a cost of nearly $800 billion/year, research on new approaches toward prevention and treatment is attracting increased attention. The consequences of noise pollution are largely preventable, but irreversible hearing loss can result from aging, disease, or drug side effects. Once damage occurs, treatment relies on hearing aids and cochlear implants. Preventing, delaying, or reducing some degree of hearing loss may be possible by avoiding excessive noise and addressing major contributory factors such as cardiovascular risk. However, given the magnitude of the problem, these interventions alone are unlikely to be sufficient. Recent advances in understanding principal mechanisms that govern hearing function, together with new drug discovery paradigms designed to identify efficacious therapies, bode well for pharmaceutical intervention. This review surveys various causes of loss of auditory function and discusses potential neurological underpinnings, including mitochondrial dysfunction. Mitochondria mitigate cell protection, survival, and function and may succumb to cumulative degradation of energy production and performance; the end result is cell death. Energy-demanding neurons and vestibulocochlear hair cells are vulnerable to mitochondrial dysfunction, and hearing impairment and deafness are characteristic of neurodegenerative mitochondrial disease phenotypes. Beyond acting as cellular powerhouses, mitochondria regulate immune responses to infections, and studies of this phenomenon have aided in identifying nuclear factor kappa B and nuclear factor erythroid 2-related factor 2/antioxidant response element signaling as targets for discovery of otologic drugs, respectively, suppressing or upregulating these pathways. Treatment with free radical scavenging antioxidants is one therapeutic approach, with lipoic acid and corresponding carnitine esters exhibiting improved biodistribution and other features showing promise. These compounds are also histone deacetylase (HDAC) inhibitors, adding epigenetic modulation to the mechanistic milieu through which they act. These data suggest that new drugs targeting mitochondrial dysfunction and modulating epigenetic pathways via HDAC inhibition or other mechanisms hold great promise.

Down-expression of P2RX2, KCNQ5, ERBB3 and SOCS3 through DNA hypermethylation in elderly women with presbycusis

CONTEXT

Presbycusis, an age-related hearing impairment (ARHI), represents the most common sensory disability in adults. Today, the molecular mechanisms underlying presbycusis remain unclear. This is in particular due to the fact that ARHI is a multifactorial complex disorder resulting from several genomic factors interacting with lifelong cumulative effects of: disease, diet, and environment.

OBJECTIVE

Identification of novel biomarkers for presbycusis.

MATERIALS AND METHODS

We selectively ascertained 18 elderly unrelated women lacking environmental and metabolic risk factors. Subsequently, we screened for methylation map changes in blood samples of women with presbycusis as compared to controls, using reduced representation bisulfite sequencing. We focused on hypermethylated cytosine bases located in gene promoters and the first two exons. To elucidate the related gene expression changes, we performed transcriptomic study using gene expression microarray.

RESULTS

Twenty-seven genes, known to be expressed in adult human cochlea, were found in the blood cells to be differentially hypermethylated with significant (p < 0.01) methylation differences (>30%) and down-expressed with fold change >1.2 (FDR <0.05). Functional annotation and qRT-PCR further identified P2RX2, KCNQ5, ERBB3 and SOCS3 to be associated with the progression of ARHI.

DISCUSSION AND CONCLUSION

Down-expressed genes associated with DNA hypermethylation could be used as biomarkers for understanding complex pathogenic mechanisms underlying presbycusis.

Hearing loss and associated medical conditions among individuals 65 years and older

BACKGROUND

Hearing loss is prevalent, but few studies have investigated its associations with common medical conditions.

OBJECTIVE

The objective was to assess the prevalence of medical conditions among individuals with hearing loss, compared to those without hearing loss, in people aged 65 years and older.

METHODS

The National Health Interview Survey (NHIS) collects data on a variety of health-related topics, including disability. Three years of NHIS data (2011-2013; unweighted n = 53,111) were pooled to examine subpopulations of individuals with hearing loss. Comparisons were made between adults aged 65 and older with, and without, self-reported hearing loss. Statistical analysis included descriptive frequencies, Chi-square tests, and multiple logistic regressions. The outcomes of interest included self-reported diagnosis of arthritis, cardiovascular disease, diabetes, high blood pressure, emphysema, stroke, cancer, asthma, multiple chronic conditions, health status, and obesity.

RESULTS

Hearing loss prevalence was nearly 37%. After adjusting for sociodemographics, smoking status, and disability, hearing loss was independently associated with the following conditions: arthritis (OR 1.41; 1.27-1.57), cancer (OR 1.35; 1.21-1.5), cardiovascular disease (OR 1.48; 1.33-1.66), diabetes (OR 1.16; 1.03-1.31), emphysema (OR 1.41; 1.14-1.74), high blood pressure (OR 1.29; 1.17-1.43), and stroke (OR 1.39; 1.12-1.66). There was an association with worse health status over the past year (OR 1.5 (1.3-1.73).

CONCLUSIONS

Hearing loss among older individuals is independently associated with increased disease burden and poorer self-reported health. Future studies are needed to investigate the mechanistic nature of these associations, and whether improved access to hearing healthcare surveillance can reduce the overall health burden among these individuals.