Association of anemia with sensorineural hearing loss: a systematic review and meta-analysis

The association between anemia and sensorineural hearing loss: A review

Anemia affects a third of the world's population and contributes to increased morbidity and mortality, decreased work productivity, and impaired neurological development. In recent years, many studies have found a possible association between anemia and sensorineural hearing loss (SNHL), especially in various types of nutritional deficiency and hemoglobin disorders anemia. Anemia may affect hearing through various mechanisms, including affecting microcirculation in the ear, causing tissue hypoxia in the ear, and through inflammatory and oxidative stress pathways. This review aims to comprehensively analyze the association between various types of anemia and SNHL, including possible biological mechanisms, clinical features, and treatment strategies, and clarify the importance of anemia treatment and management in preventing SNHL.

Dietary mineral intake and risk of bladder cancer: a systematic review and meta-analysis

This meta-analysis aimed to investigate the association between dietary mineral intake and the risk of bladder cancer. Relevant studies on bladder cancer and dietary mineral intake, including sodium, calcium, iron, magnesium, phosphorus, potassium, and zinc, were systematically identified through searches in Scopus and PubMed up to July 2024. Data from 12 studies were pooled using odds ratios (OR) and 95% confidence intervals (CI) with a random-effects model. The meta-analysis of 12 studies indicated a positive association between higher dietary sodium intake and bladder cancer risk (OR = 1.62, 95% CI: 1.04-2.55), with significant heterogeneity observed. No clear linear or nonlinear dose-response relationship was found for sodium intake. However, no significant associations were found between the intake of other minerals and the risk of bladder cancer. This study suggests that a high intake of sodium is significantly associated with an increased risk of bladder cancer. Further research is needed to explore the potential mechanisms underlying this relationship.

The Association between Dietary Intakes of Vitamins and Minerals with Tinnitus

BACKGROUND

Tinnitus is the phantom perception of sound in the ears or head which may result from inflammation of the auditory pathway. A healthy diet consisting of a range of vitamins and minerals may be protective against tinnitus. This study aims to determine the association between intakes of dietary vitamins and minerals and the prevalence and incidence of tinnitus over 10 years.

METHODS

In this longitudinal cohort study of 2947 participants (aged ≥ 50 years), 935 (32%) cases of tinnitus were identified and included in prevalence analyses. The remaining 2012 participants were followed to establish 10-year incidence of tinnitus. A validated semi-quantitative food frequency questionnaire was used to determine intakes of dietary vitamins and minerals.

RESULTS

No significant associations with tinnitus prevalence were found. However, iron and zinc were significantly associated with incident tinnitus. There was a 44% (multivariate-adjusted HR: 1.44, 95% CI: 1.07-1.93) increased risk of developing incident tinnitus over 10 years with lower zinc intakes and a 35% increased risk with lower iron intakes (multivariate-adjusted HR: 1.35, 95% CI: 1.00-1.80).

CONCLUSION

Higher intakes of zinc and iron were significantly associated with lower tinnitus risk. Due to a lack of comparable high-quality data, future research studies should include robust study designs.

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.

Hearing Loss and Disorders: The Repercussions of Climate Change

PURPOSE

Climate change is considered to be the greatest threat to human health in the 21st century, and its effects are accelerating. Extensive research has clearly demonstrated its increasing impact across the continuum of health conditions. Despite this, there has been limited attention to the ramifications of climate change on hearing loss and hearing disorders. This lack of consideration is somewhat surprising as the environment itself and its changing nature have a substantial effect on hearing.

METHOD

Tackling climate change could be the greatest global health opportunity of the 21st century. To address this issue, this tutorial provides a general introduction to climate change and its three major elements (pollution, infectious diseases, and extreme weather events) and their effects on health. The substantial consequences of climate change for the incidence, development, and exacerbation of hearing loss and disorders are clearly described and detailed.

CONCLUSIONS

The challenge of responding to this very real and escalating threat to hearing requires a combination of prevention, advocacy, and education. These three roles place audiologists in the perfect position to take action on the far-reaching effects of climate change on hearing loss and disorders. To respond to this challenge and to fulfill these roles, several strategies, ranging from the individual level to the global level, are delineated for audiologists to incorporate into their practice.

Auditory Steady-State Response and Hearing Impairment in Survivors of Childhood Bacterial Meningitis in Luanda, Angola

Survivors of childhood bacterial meningitis (BM) often develop hearing impairment (HI). In low- and middle-income countries (LMICs), BM continues to be a significant cause of hearing disability. We assessed hearing among BM survivors using auditory steady-state responses (ASSR), providing frequency-specific estimated audiograms, and examined whether ASSR would provide a greater understanding of BM-induced HI. Survivors from two prospective BM trials (ISRCTN62824827; NCT01540838) from Luanda Children's Hospital were examined in a follow-up visit with a median duration of 26 months after BM. The hearing of 50 BM survivors and 19 control children was evaluated using ASSR and auditory brainstem response (ABR) after interview and neurological and otorhinolaryngological examinations. The median age of survivors was 80 (IQR 86) months. We diagnosed HI (better ear hearing ≥ 26 dB) in 9/50 (18%) children. Five of the fifty survivors (10%) and 14/100 ears (14%) had profound HI (>80 dB). Severe-to-profound HI affected all frequencies steadily, affecting only the ears of BM survivors (18/100 vs. 0/38, p = 0.003). When looking only at the severely or profoundly affected ears, young age, low Glascow coma score, pneumococcal aetiology, and ataxia were associated with a worse hearing outcome.

Study of Association of Sensory Neural Hearing Loss with Iron Deficiency Anaemia

Hearing loss is an ignored community health problem. Along with various mental and motor developmental impairments, iron deficiency anemia (IDA) may cause hearing abnormalities. Study aimed to correlate the Sensorineural hearing loss with iron deficiency anemia in adults. This case control study conducted. Total of 200 participants fulfilling the inclusion criteria were included in present study and grouped into group 1 as cases and group 2 as controls. The participants included in present study after obtaining the consent and evaluated for the iron profile, PTA, OAE for sensory neural hearing loss. They were followed up for 3 months and 6 months. The mean age of case was 41.9 ± 10.77 and there was female preponderance in present study with 120 female and 80 males. Among 100 participants with iron deficiency anemia, twenty among them had the SNHL. The hearing impairment improved with the treatment of the IDA in patients in follow-up. There is a significant association between the SNHL and the Iron deficiency anemia in the patient. The treatment of IDA improves the hearing loss among the adults.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-021-02619-4.

Estimated Glomerular Filtration Rate and Hearing Impairment in Japan: A Longitudinal Analysis Using Large-Scale Occupational Health Check-Up Data

Several longitudinal studies have examined associations between renal dysfunction and hearing impairment. Here, we explored the longitudinal association between estimated glomerular filtration rate (eGFR) and hearing impairment among the working-age population in Japan. Participants were 88,425 males and 38,722 females aged 20-59 years, without hearing impairment at baseline (2013), who attended Japanese occupational annual health check-ups from 2013 to 2020 fiscal year. eGFR was categorized into four groups (eGFR upper half of ≥90, lower half of ≥90 (reference), 60-89, and <60 mL/min/1.73 m²). Low- and high-frequency hearing impairment were assessed using data from pure-tone audiometric testing. A Cox proportional hazards model was applied to estimate hazard ratio (HR) values for hearing impairment. Low eGFR did not increase the risk of low- or high-frequency hearing impairment. For males, multivariable-adjusted HR of high-frequency hearing impairment was 1.16 (95% confidence interval, 1.01-1.34) for the upper half of the ≥90 mL/min/1.73 m²; however, this positive association between high eGFR and high-frequency hearing impairment did not appear to be robust in a number of sensitivity analyses. We conclude that, among the Japanese working-age population, eGFR was not generally associated with hearing impairment in people of either sex.

The prevalence of anemia and its associations with other geriatric syndromes in subjects over 65 years old: data of Russian epidemiological study EVKALIPT

Background. A low hemoglobin level in older adults impairs cognitive ability and functional status and associates with risk of falls and fractures, sarcopenia, malnutrition, depression, frailty, and decreased autonomy. Epidemiological data on the anemia prevalence in the geriatric population in our country is not available. Aim. To assess the prevalence of anemia and analyze its associations with geriatric syndromes (GS) in subjects aged 65 years. Materials and methods. 4308 subjects (30% of men) aged 65107 years, living in 11 regions of the Russian Federation, were examined and divided into age groups (6574 years, 7584 years and 85 years). All the participants underwent a comprehensive geriatric assessment and determined hemoglobin level. Results. The anemia prevalence in older adults was 23.9%. It has been shown that with an increase in age per 1 year, the risk of anemia detection increases by 4%. The incidence of anemia was higher in males than females (28.1% versus 22.1%; p0.001). In most cases, anemia was mild. The results of a comprehensive geriatric assessment show that patients with anemia had lower hand grip force, Barthel Index, the sum of points on Lawton instrumental activities of daily living scale, Mini Nutritional Assessment scale, the Mini-Cog test and higher the sum of points on the Geriatric Depression Scale (GDS-15) and the Age Is No Barrier scale. Patients with anemia were more likely to use hearing aids, absorbent underwear, and assistive devices during movement. Patients with anemia had a higher incidence of all GS, except for orthostatic hypotension and chronic pain syndrome. The presence of GS is associated with an increased risk of anemia by 1.33.4 times. Conclusion. EVKALIPT study obtained domestic data on the prevalence of anemia in older patients and examined its associations with other GS.

[Triggers and predictors of development and formation of sensorineural hearing loss]

The purpose of the study is to review the results of scientific researches in recent years in an expanded interdisciplinary view of the problem of etiopathogenesis of sensorineural hearing loss, as well as the role of comorbidities and triggers in the formation of persistent changes in the audio-receiving part of the auditory analyzer.

Relationship Between Peripheral and Central Auditory Abilities and Iron Deficiency Anemia in Adolescent Girls

PURPOSE

This study evaluated the peripheral hearing and central auditory processing abilities in Indian adolescent girls with iron deficiency anemia (IDA).

METHOD

The participants consisted of 75 adolescent girls with IDA, 50 adolescent girls without IDA, and 50 adolescent boys without IDA. Participants underwent a test battery to evaluate auditory processing and peripheral hearing assessment. In this study, central auditory processing abilities were assessed using Speech Perception in Noise test in Kannada (SPIN-K) and quick speech perception in noise tests in Kannada, dichotic consonant-vowel test, gap detection threshold (GDT), and auditory digit sequencing and auditory digit span tests.

RESULTS

Results showed that the hearing thresholds at extremely low and high frequencies (250 and 8000 Hz), although within clinically normal limits, were poorer in girls with IDA than in the control groups. Also, girls with IDA performed poorly in SPIN-K of the right ear, GDT, and auditory backward digit span tests.

CONCLUSION

These subtle auditory deficiencies may be attributed to the compromised blood supply to the central auditory nervous system, as observed in the current study.

Investigation of the Interaction between Hearing Function and Comorbidities in Adults Living with Human Immunodeficiency Virus

Adults living with the human immunodeficiency virus (HIV) have a high prevalence of co-existing comorbidities. While research indicates that adults living with HIV are at risk of developing hearing impairment, limited research exists on the interaction between hearing function and comorbidities in this population. The objective of this study was to determine and compare the hearing function of a group of adults living with HIV and comorbidities and those without comorbidities. A sample of 132 adults living with HIV underwent a basic audiological test battery to assess their hearing function. Participants with comorbidities were 1.23 times more likely to develop hearing loss, with crude odds of 1.236 (95%CI 0.5467 to 2.795), while those with three comorbidities were 2.52 times more likely to develop hearing loss. Participants with hypertension were 93% more likely to develop hearing loss when compared to nonhypertensive participants (OR = 1.928; 95%CI: 0.7856 to 4.7345). There was only a marginal association between hypercholesterolemia and sensorineural hearing loss (SNHL), with no association between other comorbidities and the type of hearing loss. The current findings raise a need for prioritizing patients with comorbidities in audiological assessment and monitoring in resource-constrained contexts, where capacity versus demand challenges might prevent the provision of audiological services to all adults living with HIV. These findings also highlight the importance of preventive care in this population with regard to the burden of the disease, as it may lead to worse ear and hearing outcomes for affected individuals.

Hearing impairment and diverse health outcomes : An umbrella review of meta-analyses of observational studies

BACKGROUND

Globally, it is estimated that approximately 1.3 billion people live with some form of hearing impairment. Major causes of hearing loss include infection/disease, age-related factors, and occupational factors. Numerous systematic reviews and meta-analyses have attempted to synthesise literature on these topics. To date there has not been a systematic evaluation of the relationships between hearing impairment and diverse physical, mental, and social outcomes.

OBJECTIVE

We performed an umbrella review of systematic reviews of observational studies with meta-analyses for any physical disease, biomarkers of disease, mental health or cognitive outcomes, and/or modifiable risk factors associated with hearing impairment.

METHODS

For each meta-analytic association, random effects summary effect size, 95% confidence intervals, heterogeneity, evidence for small-study effect, excess significance bias and 95% prediction intervals were calculated, and risk of bias was assessed via the AMSTAR2 tool. These were used to grade significant evidence (p < 0.05) from I to IV, using the recommendations from the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

From 3747 studies, 21 were included covering 54 outcomes. Overall, 44/54 outcomes (82%) yielded significant results. Of the highest quality evidence, age-related hearing loss and non-specific hearing impairment were negatively associated with several types of cognitive impairments; pediatric bilateral hearing loss was negatively associated with quality of life, sensorineural hearing loss was positively associated with rheumatoid arthritis and tinnitus was positively associated with temporomandibular disorders.

CONCLUSION AND RELEVANCE

Results show moderate quality evidence for associations between several types of hearing impairments and cognitive difficulties, quality of life and systemic diseases such as rheumatoid arthritis. Practitioners and public health policies should note these findings when developing relevant healthcare policies.

Characterization of Sensorineural Hearing Loss in Adult Patients With Sickle Cell Disease: A Systematic Review and Meta-analysis

OBJECTIVES AND MAIN OUTCOME MEASURES

To determine the prevalence of sensorineural hearing loss (SNHL) attributable to sickle cell disease (SCD) in the global adult population and to identify factors contributing to its severity.

STUDY DESIGN

Systematic Review and Meta-analysis.

METHODS

We performed a comprehensive literature search for scientific articles in PubMed, Scopus, CINAHL, Web of Science, and the Cochrane Library that reported the incidence of hearing loss in populations over 18 years of age with SCD.

RESULTS

We identified 138 studies from the initial search, 12 of which met inclusion criteria and were utilized for data analysis. A total of 636 SCD patients and 360 controls were included in the Cochrane Review Manager 5.3 meta-analysis. There was a statistically significant increase in the prevalence of SNHL in adults with SCD compared with the general population with a cumulative risk ratio (RR) of 6.03.

CONCLUSIONS

This is the first systematic investigation of the relationship between SCD and SNHL in adult patients across the globe. SNHL is more prevalent in patients with SCD, specifically those of the HbSS genotype, than the general population likely due to the pathophysiology of the disease and its effects on labyrinthine microvasculature. The increased prevalence of SNHL in the adult SCD population warrants future research into the predictors of SNHL severity and merits routine audiometric monitoring of adult SCD patients.

Audiological and otologic manifestations of glutaric aciduria type I

Background

Glutaric aciduria type 1 (GA-1) is a rare disease connected with speech delay and neurological deficits. However, the audiological and otologic profiles of GA-1 have not yet been fully characterized. To our knowledge, this is the largest study of comprehensive audiological and otologic evaluation in patients with GA-1 to date.

Methods

Thirteen patients diagnosed with GA-1 between January 1994 and December 2019 with audiological, radiological and genetic manifestations were retrospectively analyzed. Hearing tests were performed in all patients. MRI was performed for radiological evaluation.

Results

Hearing loss was found in 76.9% (10/13) of GA-1 patients, including slight hearing loss in 46.1% (6/13) of patients, mild hearing loss in 15.4% (2/13) of patients, and moderate hearing loss in 7.7% (1/13) of patients. Normal hearing thresholds were seen in 23% (3/13) of patients. Patients with intensive care unit (ICU) admission history showed significantly worse hearing than those without (29.17 ± 12.47 vs 13.56 ± 3.93 dB HL, 95% CI 2.92–24.70, p = 0.0176). One patient had moderate sensorineural hearing loss and a past history of acute encephalopathic crisis. No usual causative gene mutations associated with hearing loss were found in these patients. MRI showed a normal vestibulocochlear apparatus and cochlear nerve. One patient with extensive injury of the basal ganglia on MRI after acute encephalopathic crisis was found to have moderate sensorineural hearing loss. Two patients with disability scores above 5 were found to have mild to moderate hearing impairment. No obvious correlation between macrocephaly and hearing loss was found.

Conclusion

A high prevalence of hearing impairment is found in GA-1 patients. Adequate audiological evaluation is essential for these patients, especially for those after encephalopathic crises or with ICU admission history.

Prevalence of Sensorineural Hearing Loss in Pediatric Patients with Sickle Cell Disease: A Meta-analysis

OBJECTIVES

To determine the prevalence of Sensorineural Hearing Loss (SNHL) attributable to Sickle Cell Disease (SCD) in the global pediatric population and to identify factors contributing to its severity.

STUDY DESIGN

Meta-analysis.

METHODS

We performed a comprehensive literature search for scientific articles in PubMed, Scopus, CINAHL, Web of Science, and the Cochrane Library that reported the incidence of hearing loss in populations under 18 years of age with excluding studies analyzing patients on iron chelation therapy, adults, or those without objective audiological analysis.

RESULTS

We identified 138 initial studies with 17 selected for analysis after applying the exclusion criteria. A total of 1,282 SCD patients and 553 controls were included in the meta-analysis. There was a statistically significant increase in the prevalence of SNHL in children with SCD compared to the general population with a cumulative risk ratio of 3.33.

CONCLUSION

This is the first systematic investigation of the relationship between SCD and SNHL in pediatric patients across the globe. The increased prevalence of SNHL in the pediatric SCD population warrants future research into the predictors of SNHL severity and merits routine audiometric monitoring of SCD patients to reduce the social and developmental morbidity of hearing loss at a young age. PROSPERO Registration #: CRD42019132601. Laryngoscope, 131:1147-1156, 2021.

Association between Anemia and Auditory Threshold Shifts in the US Population: National Health and Nutrition Examination Survey

Existing evidence indicates that both iron deficiency anemia and sickle cell anemia have been previously associated with hearing loss. However, human data investigating the association between anemia and auditory threshold shifts at different frequencies in the adolescent, adult and elderly population are extremely limited to date. Therefore, this cross-sectional study used the dataset from the US National Health and Nutrition Examination Survey from 2005 to 2012 to explore differences in low- or high-frequency hearing thresholds and hearing loss prevalence between participants with and without anemia. A total of 918 patients with anemia and 8213 without anemia were included. Results indicated that low- and high-frequency pure tone average were significantly higher in patients with anemia than that in those without anemia in the elderly, but not in adult or adolescent population. In addition, the prevalence of low-frequency hearing loss but not high-frequency hearing loss was also higher in patients with anemia than in those without anemia in the elderly population. After adjusting various confounders, multiple regression models still indicated that patients with anemia tended to have larger threshold shift. In conclusion, anemia was associated with auditory threshold shifts in the elderly population, especially those vulnerable to low-frequency hearing loss.

The contribution of dietary and non-dietary factors to socioeconomic inequality in childhood anemia in Ethiopia: a regression-based decomposition analysis

Objective

There is a scarcity of evidence on socioeconomic inequalities of childhood anemia in Ethiopia. We determined the magnitude of socioeconomic inequality in anemia and the contribution of dietary and non-dietary factors to the observed inequality, using a nationally representative data of 2902 children included in the 2016 Ethiopian demographic and health survey. The data were collected following a multistage, stratified cluster sampling strategy. We followed the Blinder–Oaxaca regression-based approach to decompose the inequality and determine the relative contribution (%) of the dietary and non-dietary factors to the observed inequality.

Result

We found a significant pro-poor socioeconomic inequality in childhood anemia in Ethiopia. A third (~ 33%) of the inequality was attributable to compositional differences in the dietary determinants of anemia (dietary diversity, meal frequency, and breastfeeding factors). Non-dietary factors like residence place, maternal education, and birth weight) jointly explained ~ 36% of the inequality. Maternal education was the single most important factor, accounting alone for ~ 28% the inequality, followed by rural residence (~ 17%) and dietary diversity (~ 16%). Efforts to narrow socioeconomic gaps and/or designing equity sensitive interventions by prioritizing the poor in health/nutrition interventions stands worth of consideration to reduce the burden of childhood anemia in Ethiopia and beyond.