Alcohol as a risk factor for hearing loss: A systematic review and meta-analysis

Environmental Risk Factors, Protective Factors, and Biomarkers for Hearing Loss: An Umbrella Review

OBJECTIVE

We aimed to investigate the potential environmental risk factors, protective factors, and biomarkers of hearing loss (HL), and establish a hierarchy of evidence.

DATA SOURCES

Embase, PubMed, Cochrane Library, and Web of Science electronic database from inception to June 1, 2023.

REVIEW METHODS

We included meta-analyses of observational studies of associations between HL and environmental risk factors, protective factors, or biomarkers. We calculated summary effect estimates, 95% confidence interval, heterogeneity I2 statistic, 95% prediction interval, small study effects, and excess significance biases.

RESULTS

Of the 9211 articles retrieved, 60 eligible articles were included. The 60 eligible articles identified 47 potential environmental risk and protective factors (N = 4,123,803) and 46 potential biomarkers (N = 173,701). Evidence of association was convincing (class I) for rheumatoid arthritis (RA) and every 1 cm increase in height. Evidence of association was highly suggestive (class II) for human immunodeficiency virus (HIV), diabetes, cumulative noise exposure (CNE), smoking, congenital cytomegalovirus (CMV) infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and alopecia areata (AA).

CONCLUSION

In this umbrella review, RA, every 1 cm increase in height, HIV, diabetes, CNE, smoking, congenital CMV infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and AA were strongly associated with HL.

Association of oxidative balance score with hearing loss and tinnitus: NHANES 1999-2018

Background

Oxidative stress is associated with the occurrence of hearing loss and tinnitus. The oxidative balance score (OBS), a composite indicator evaluating the balance between antioxidant and pro-oxidative components across various dietary and lifestyle factors, indicates the overall oxidative balance status. However, the association of OBS with hearing loss and tinnitus has not been reported previously.

Methods

Cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 were analyzed. Weighted multivariable logistic regression, weighted multivariable linear regression, and restricted cubic spline curve (RCS) regression were employed to explore the relationship between OBS and hearing loss at speech, low, and high frequencies, along with tinnitus. Subgroup analysis and sensitivity analysis were used to ascertain the consistency across subgroups and stability of the results.

Results

We included 13,715 and 21,644 individuals to investigate the association between OBS and hearing loss, as well as between OBS and tinnitus, respectively. The second, third, and fourth quartiles of OBS were significantly associated with a lower risk of hearing loss at speech, low, and high frequencies, as well as tinnitus, compared to the lowest quartile. The RCS regression analysis indicated a negative linear association of OBS with hearing loss and tinnitus. Most associations were maintained in subgroup analysis and sensitivity analysis. Additionally, the dietary and lifestyle OBS independently contribute to the protection against hearing loss and tinnitus.

Conclusion

OBS is negatively correlated with the risk of hearing loss and tinnitus. The findings suggest that combined antioxidant diet and lifestyle hold promise as potential strategies for reducing the prevalence of hearing loss and tinnitus.

Polygenic Risk Score-Based Association Analysis Identifies Genetic Comorbidities Associated with Age-Related Hearing Difficulty in Two Independent Samples

PURPOSE

Age-related hearing loss is the most common form of permanent hearing loss that is associated with various health traits, including Alzheimer's disease, cognitive decline, and depression. The present study aims to identify genetic comorbidities of age-related hearing loss. Past genome-wide association studies identified multiple genomic loci involved in common adult-onset health traits. Polygenic risk scores (PRS) could summarize the polygenic inheritance and quantify the genetic susceptibility of complex traits independent of trait expression. The present study conducted a PRS-based association analysis of age-related hearing difficulty in the UK Biobank sample (N = 425,240), followed by a replication analysis using hearing thresholds (HTs) and distortion-product otoacoustic emissions (DPOAEs) in 242 young adults with self-reported normal hearing. We hypothesized that young adults with genetic comorbidities associated with age-related hearing difficulty would exhibit subclinical decline in HTs and DPOAEs in both ears.

METHODS

A total of 111,243 participants reported age-related hearing difficulty in the UK Biobank sample (> 40 years). The PRS models were derived from the polygenic risk score catalog to obtain 2627 PRS predictors across the health spectrum. HTs (0.25-16 kHz) and DPOAEs (1-16 kHz, L1/L2 = 65/55 dB SPL, F2/F1 = 1.22) were measured on 242 young adults. Saliva-derived DNA samples were subjected to low-pass whole genome sequencing, followed by genome-wide imputation and PRS calculation. The logistic regression analyses were performed to identify PRS predictors of age-related hearing difficulty in the UK Biobank cohort. The linear mixed model analyses were performed to identify PRS predictors of HTs and DPOAEs.

RESULTS

The PRS-based association analysis identified 977 PRS predictors across the health spectrum associated with age-related hearing difficulty. Hearing difficulty and hearing aid use PRS predictors revealed the strongest association with the age-related hearing difficulty phenotype. Youth with a higher genetic predisposition to hearing difficulty revealed a subclinical elevation in HTs and a decline in DPOAEs in both ears. PRS predictors associated with age-related hearing difficulty were enriched for mental health, lifestyle, metabolic, sleep, reproductive, digestive, respiratory, hematopoietic, and immune traits. Fifty PRS predictors belonging to various trait categories were replicated for HTs and DPOAEs in both ears.

CONCLUSION

The study identified genetic comorbidities associated with age-related hearing loss across the health spectrum. Youth with a high genetic predisposition to age-related hearing difficulty and other related complex traits could exhibit sub-clinical decline in HTs and DPOAEs decades before clinically meaningful age-related hearing loss is observed. We posit that effective communication of genetic risk, promoting a healthy lifestyle, and reducing exposure to environmental risk factors at younger ages could help prevent or delay the onset of age-related hearing difficulty at older ages.

Association of conventional cigarette smoking, heated tobacco product use, and dual use with hearing loss: A working population-based study

INTRODUCTION

Although conventional cigarette smoking has been linked to an increased risk of hearing loss, the association between heated tobacco products (HTPs) and hearing loss is unknown. The objective of this study was to investigate the association between cigarette and HTP use and hearing loss.

METHODS

This cross-sectional study examined the data of 7769 employees from five companies (Study I) and 34404 employees from a large company (Study II), all participants in the Japan Epidemiology Collaboration on Occupational Health Study. The participants were categorized into five groups based on their self-reported tobacco use: never smokers, former smokers, exclusive cigarette smokers, exclusive users of HTPs, and those who used both cigarettes and HTPs. Hearing levels were measured using pure-tone audiometry at 1 and 4 kHz frequencies. Separate analyses were carried out for each study, and the results were then combined using fixed-effect models to pool the estimates.

RESULTS

The analysis included 42173 participants, with a prevalence of 12.9% for exclusive cigarette smoking, 9.8% for exclusive HTP use, and 5.5% for dual use. The pooled adjusted odds ratios with 95% confidence intervals for unilateral hearing loss at 4 kHz were 1.21 (95% CI: 1.10-1.33) for former smokers, 1.83 (95% CI: 1.64-2.05) for exclusive cigarette smokers,1.46 (95% CI: 1.28-1.67) for exclusive HTP users, and 1.66 (95% CI: 1.41-1.96) for dual users, compared to never smokers. Additionally, the adjusted odds ratios for hearing loss at 4 kHz among exclusive cigarette smokers, exclusive HTP users, and dual users increased with the intensity of cigarette/HTP consumption (all p for trend <0.001). No significant associations were found between exclusive HTP use, dual use, and hearing loss at 1 kHz, apart from exclusive cigarette smoking.

CONCLUSIONS

In this cross-sectional study, associations were found between exclusive cigarette smoking, exclusive HTP use, dual use, and hearing loss, particularly at 4 kHz. Further research is needed to confirm these findings.

A machine learning screening model for identifying the risk of high-frequency hearing impairment in a general population

BACKGROUND

Hearing impairment (HI) has become a major public health issue in China. Currently, due to the limitations of primary health care, the gold standard for HI diagnosis (pure-tone hearing test) is not suitable for large-scale use in community settings. Therefore, the purpose of this study was to develop a cost-effective HI screening model for the general population using machine learning (ML) methods and data gathered from community-based scenarios, aiming to help improve the hearing-related health outcomes of community residents.

METHODS

This study recruited 3371 community residents from 7 health centres in Zhejiang, China. Sixty-eight indicators derived from questionnaire surveys and routine haematological tests were delivered and used for modelling. Seven commonly used ML models (the naive Bayes (NB), K-nearest neighbours (KNN), support vector machine (SVM), random forest (RF), eXtreme Gradient Boosting (XGBoost), boosting, and least absolute shrinkage and selection operator (LASSO regression)) were adopted and compared to develop the final high-frequency hearing impairment (HFHI) screening model for community residents. The model was constructed with a nomogram to obtain the risk score of the probability of individuals suffering from HFHI. According to the risk score, the population was divided into three risk stratifications (low, medium and high) and the risk factor characteristics of each dimension under different risk stratifications were identified.

RESULTS

Among all the algorithms used, the LASSO-based model achieved the best performance on the validation set by attaining an area under the curve (AUC) of 0.868 (95% confidence interval (CI): 0.847-0.889) and reaching precision, specificity and F-score values all greater than 80%. Five demographic indicators, 7 disease-related features, 5 behavioural factors, 2 environmental exposures, 2 hearing cognitive factors, and 13 blood test indicators were identified in the final screening model. A total of 91.42% (1235/1129) of the subjects in the high-risk group were confirmed to have HI by audiometry, which was 3.99 times greater than that in the low-risk group (22.91%, 301/1314). The high-risk population was mainly characterized as older, low-income and low-educated males, especially those with multiple chronic conditions, noise exposure, poor lifestyle, abnormal blood indices (e.g., red cell distribution width (RDW) and platelet distribution width (PDW)) and liver function indicators (e.g., triglyceride (TG), indirect bilirubin (IBIL), aspartate aminotransferase (AST) and low-density lipoprotein (LDL)). An HFHI nomogram was further generated to improve the operability of the screening model for community applications.

CONCLUSIONS

The HFHI risk screening model developed based on ML algorithms can more accurately identify residents with HFHI by categorizing them into the high-risk groups, which can further help to identify modifiable and immutable risk factors for residents at high risk of HI and promote their personalized HI prevention or intervention.

Variations in the Cadherin 23 Gene Associated With Noise-Induced Hearing Loss

Background

The relationship between CDH23 gene variants and NIHL is unclear. This study investigates the association between cadherin 23 (CDH23) gene variants and noise-induced hearing loss (NIHL).

Methods

This is a case-control study. Workers who were exposed to noise from a steel factory in North China were recruited and divided into two groups: the case group (both ears' high-frequency threshold average [BHFTA] ≥40dB) and the control group (BHFTA ≤25 dB). This study used the generalised multifactor dimensionality reduction method to analyse the association among 18 single-nucleotide polymorphisms (SNPs) in CDH23 and NIHL. Logistic regression was performed to investigate the main effects of SNPs and the interactions between cumulative noise exposure (CNE) and SNPs. Furthermore, CNE was adjusted for age, gender, smoking, drinking, physical exercise and hypertension.

Results

This study recruited 1,117 participants. The results showed that for rs11592462, participants who carried the GG genotype showed an association with NIHL greater than that of those who carried the CC genotype. Accordingly, genetic variation in the CDH23 gene could play an essential role in determining individual susceptibility to NIHL.

Conclusion

Genetic variations in the CDH23 gene may play an important role in determining individual susceptibility to NIHL. These results provide new insight into the pathogenesis and early prevention of NIHL.

Sex differences in associated factors for age-related hearing loss

The prevalence and age of onset of hearing loss differ according to sex. This study aimed to identify associated factors for age-related hearing loss (ARHL) and determine whether there are differences between males and females regarding associated factors for ARHL. This cross-sectional study used data from adults who underwent medical examinations including hearing tests from 2011 to 2021. A total of 2,349 individuals were included. The study conducted sex-specific analyses using both univariate and multiple regression. Univariate analysis employed logistic regression, while multiple regression involved variable selection through the augmented backward elimination method. Separate multiple logistic regression analyses were conducted for each sex. In the univariate analysis, among males, age, underweight, alcohol consumption, weight, and height exhibited statistical significance. Among females, age, hypertension, diabetes, dyslipidemia, obesity, sarcopenia, weight, height, age at menarche, and duration of hormone exposure were found to be significant factors. However, in the multiple logistic regression model for males, underweight, and smoking emerged as significant, while in females, age, weight, obesity, and age at menarche retained their significance. We found that there are different associated factors for ARHL in each sex. Assessment and counseling for smoking, obstetric history, underweight, and obesity may be beneficial in managing patients with ARHL.

Bidirectional associations between hearing difficulty and cognitive function in Chinese adults: a longitudinal study

Background

Middle-aged and older adults frequently experience hearing loss and a decline in cognitive function. Although an association between hearing difficulty and cognitive function has been demonstrated, its temporal sequence remains unclear. Therefore, we investigated whether there are bidirectional relationships between hearing difficulty and cognitive function and explored the mediating role of depressive symptoms in this relationship.

Method

We used the cross-lagged panel model and the random-intercept cross-lagged panel model to look for any possible two-way link between self-reported hearing difficulty and cognitive function. To investigate depressive symptoms' role in this association, a mediation analysis was conducted. The sample was made up of 4,363 adults aged 45 and above from the China Health and Retirement Longitudinal Study (CHARLS; 2011-2018; 44.83% were women; mean age was 56.16 years). One question was used to determine whether someone had a hearing impairment. The tests of cognitive function included episodic memory and intelligence. The Center for Epidemiologic Studies Depression Scale, which consists of 10 items, was used to measure depressive symptoms.

Results

A bidirectional association between hearing and cognition was observed, with cognition predominating (Wald χ2 (1) = 7.241, p < 0.01). At the between-person level, after controlling for potential confounders, worse hearing in 2011 predicted worse cognitive function in 2013 (β = -0.039, p < 0.01) and vice versa (β = -0.041, p < 0.01) at the between-person level. Additionally, there was no corresponding cross-lagged effect of cognitive function on hearing difficulty; rather, the more hearing difficulty, the greater the cognitive decline at the within-person level. According to the cross-lagged mediation model, depressive symptoms partially mediates the impact of cognitive function on subsequent hearing difficulty (indirect effect: -0.003, bootstrap 95% confidence interval: -0.005, -0.001, p < 0.05), but not the other way around.

Conclusion

These results showed that within-person relationships between hearing impairment and cognitive function were unidirectional, while between-person relationships were reciprocal. Setting mental health first may be able to break the vicious cycle that relates hearing loss to cognitive decline. Comprehensive long-term care requires services that address depressive symptoms and cognitive decline to be integrated with the hearing management.