Is type 2 diabetes mellitus associated with alterations in hearing? A systematic review and meta-analysis

Subclinical Auditory Neural Deficits in Patients With Type 1 Diabetes Mellitus

Supplemental Digital Content is available in the text.

Objectives:

Diabetes mellitus (DM) is associated with a variety of sensory complications. Very little attention has been given to auditory neuropathic complications in DM. The aim of this study was to determine whether type 1 DM (T1DM) affects neural coding of the rapid temporal fluctuations of sounds, and how any deficits may impact on behavioral performance.

Design:

Participants were 30 young normal-hearing T1DM patients, and 30 age-, sex-, and audiogram-matched healthy controls. Measurements included electrophysiological measures of auditory nerve and brainstem function using the click-evoked auditory brainstem response, and of brainstem neural temporal coding using the sustained frequency-following response (FFR); behavioral tests of temporal coding (interaural phase difference discrimination and the frequency difference limen); tests of speech perception in noise; and self-report measures of auditory disability using the Speech, Spatial and Qualities of Hearing Scale.

Results:

There were no significant differences between T1DM patients and controls in the auditory brainstem response. However, the T1DM group showed significantly reduced FFRs to both temporal envelope and temporal fine structure. The T1DM group also showed significantly higher interaural phase difference and frequency difference limen thresholds, worse speech-in-noise performance, as well as lower overall Speech, Spatial and Qualities scores than the control group.

Conclusions:

These findings suggest that T1DM is associated with degraded neural temporal coding in the brainstem in the absence of an elevation in audiometric threshold, and that the FFR may provide an early indicator of neural damage in T1DM, before any abnormalities can be identified using standard clinical tests. However, the relation between the neural deficits and the behavioral deficits is uncertain.

NADPH Oxidase 2-Mediated Insult in the Auditory Cortex of Zucker Diabetic Fatty Rats

Clinical data has confirmed that auditory impairment may be a secondary symptom of type 2 diabetes mellitus (T2DM). However, mechanisms underlying pathologic changes that occur in the auditory system, especially in the central auditory system (CAS), remain poorly understood. In this study, Zucker diabetic fatty (ZDF) rats were used as a T2DM rat model to observe ultrastructural alterations in the auditory cortex and investigate possible mechanisms underlying CAS damage in T2DM. The auditory brainstem response (ABR) of ZDF rats was found to be markedly elevated in low (8 kHz) and high (32 kHz) frequencies. Protein expression of NADPH oxidase 2 (NOX2) and its matching subunits P22^phox, P47^phox, and P67^phox was increased in the auditory cortex of ZDF rats. Expression of 8-hydroxy-2-deoxyguanosine (8-OHdG), a marker of DNA oxidative damage, was also increased in the neuronal mitochondria of the auditory cortex of ZDF rats. Additionally, decreases in the mitochondrial total antioxidant capabilities (T-AOC), adenosine triphosphate (ATP) production, and mitochondrial membrane potential (MMP) were detected in the auditory cortex of ZDF rats, suggesting mitochondrial dysfunction. Transmission electron microscopy results indicated that ultrastructural damage had occurred to neurovascular units and mitochondria in the auditory cortex of ZDF rats. Furthermore, cytochrome c (Cyt c) translocation from mitochondria to cytoplasm and caspase 3-dependent apoptosis were also detected in the auditory cortex of ZDF rats. Consequently, the study demonstrated that T2DM may cause morphological damage to the CAS and that NOX2-associated mitochondrial oxidative damage and apoptosis may be partly responsible for this insult.

Diabetes in the practice of otolaryngology

Diabetes mellitus is the most common endocrine disease, characterized by chronic hyperglycemia. The hyperglycemic milieu leads to endothelial injury in blood vessels of variant size, which results in microangiopathy and macroangiopathy (atherosclerosis). Consequential ischemia of nerves and hyperglycemia by itself lead to nerve degeneration and generalized neuropathy, affecting most often the sensory peripheral nerves and the autonomic nervous system. Auditory, vestibular and olfactory sensorium may be compromised by DM. People with DM have an increased susceptibility to infection, as a result of neutrophil dysfunction and impaired humoral immunity. Therefore DM predisposes to certain infectious diseases, such as fungal sinusitis or malignant otitis externa, which are rare in general population. Recovery from infections or from injuries may be compromised by coexisting DM. In this review we discuss complications of DM in the head and neck region. Otolaryngologists and general practitioners should be alert to specific conditions related to DM and be minded of the relevant complications and consequences.

Progression of Hearing Loss in the Aging Population: Repeated Auditory Measurements in the Rotterdam Study

We quantified changes in the auditory acuity of 675 aging adults (mean age 71.1 years, 52.0% female, mean follow-up 4.4 years ± 0.2) of an ongoing cohort study with a pure-tone audiogram and a speech-in-noise test. Generalized estimating equation models were used to study the association between hearing loss and the progression with age, sex, education, cognition, BMI, blood pressure, having type 2 diabetes mellitus, cholesterol ratio, smoking and alcohol consumption. The mean progression of hearing loss was 0.29 and 1.35 dB/year (low and high frequencies). Progression of hearing loss was associated with baseline hearing thresholds. Besides, the presence of type 2 diabetes, smoking, age, sex and time were associated with worse hearing at baseline, but there was no statistical evidence that the tested determinants were associated with progression of hearing loss. This finding indicates that the 4-year progression of hearing loss in older adults in this study is not influenced by the measured determinants. More research with multiple follow-up rounds is desired.

Hyperglycemia and diabetes mellitus are related to vestibular organs dysfunction: truth or suggestion? A literature review

Diabetes mellitus is an independent risk factor for falling, particularly in the elderly. Due to chronic hyperglycemia and hyperinsulinemia patients with diabetes mellitus may have neurological deficits as peripheral neuropathy that is a debilitating micro-vascular complication affecting the proximal and distal peripheral sensory and motor nerves. Sensory neuropathy is prominent and represents the chief contributor to postural instability in diabetic subjects. Diabetic retinopathy is another complication consequent to a breakdown of the inner blood-retinal barrier with accumulation of extracellular fluids in the macula and growth of new vessels causing retinal detachment. Together peripheral neuropathy and retinopathy contribute to increase the risk of falls in diabetic patients, but a certain vestibular organs impairment should not be underestimated. Nevertheless, the exact mechanism and localization of peripheral vestibular damage consequent to chronic hyperglycemia and hyperinsulinemia are currently not still understood. Moreover it is not defined the possible role of these two blood conditions in worsening the prognosis of typical vestibular pathologies like "benign paroxysmal positional vertigo" and "Meniere disease". The aim of this review was to retrieve all studies investigating about the balance system alterations in patients suffering of diabetes. A search thorough Ovid MEDLINE was performed to enroll all eligible articles. Fourteen studies comprising a total of 1364 patients were included and analyzed in detail. On the basis of data reported in our review it appears plausible to hypothesize a direct connection among chronic hyperglycemic/hyperinsulinemic damage and peripheral vestibular organ dysfunction.

Effects of diabetes mellitus and systemic arterial hypertension on elderly patients' hearing

INTRODUCTION

Chronic diseases can act as an accelerating factor in the auditory system degeneration. Studies on the association between presbycusis and diabetes mellitus and systemic arterial hypertension have shown controversial conclusions.

OBJECTIVE

To compare the initial audiometry (A1) with a subsequent audiometry (A2) performed after a 3 to 4-year interval in a population of elderly patients with diabetes mellitus and/or systemic arterial hypertension, to verify whether hearing loss in these groups is more accelerated when compared to controls without these clinical conditions.

METHODS

100 elderly individuals participated in this study. For the auditory threshold assessment, a previous complete audiological evaluation (A1) and a new audiological evaluation (A2) performed 3-4 years after the first one was utilized. The participants were divided into four groups: 20 individuals in the diabetes mellitus group, 20 individuals in the systemic arterial hypertension group, 20 individuals in the diabetes mellitus/systemic arterial hypertension group and 40 individuals in the control group, matching them with each study group, according to age and gender. ANOVA and Kruskal-Wallis statistical tests were used, with a significance level set at 0.05.

RESULTS

When comparing the mean annual increase in the auditory thresholds of the A1 with the A2 assessment, considering each study group and its respective control, it can be observed that there was no statistically significant difference for any of the frequencies for the diabetes mellitus group; for the systemic arterial hypertension group, significant differences were observed after 4kHz. For the diabetes mellitus and systemic arterial hypertension group, significant differences were observed at the frequencies of 500, 2kHz, 3kHz and 8kHz.

CONCLUSION

It was observed that the systemic arterial hypertension group showed the greatest decrease in auditory thresholds in the studied segment when compared to the other groups, suggesting that among the three studied conditions, hypertension seems to have the greatest influence on hearing.

Hearing loss in type 1 diabetes: Are we facing another microvascular disease? A meta-analysis

OBJECTIVE

Evidence shows type 1 diabetes(T1D) leads to vascular damage and neuropathy. The purpose of this study was to perform a systematic review and a meta-analysis to assess the evidence of the effects of T1D on hearing function.

METHODS

Three electronic databases were used. The articles were independently reviewed by two authors using predefined inclusion criteria to identify eligible studies. They were then classified as high or low methodological quality. Meta-analysis was performed on pooled data of hearing loss(HL) prevalence, pure tone audiometry(PTA), otoacoustic emissions(OAE) and auditory brainstem response(ABR).

RESULTS

Twenty-one articles fulfilled the inclusion criteria. In all studies, HL was defined as pure tone greater than 20 dB in at least one frequency. The prevalence of HL ranged between 5.17% and 48% for diabetics, which was higher than in controls which ranged between 0% à 40% (OR = 7.7, 95% CI 3.32-17.98, p < 0.05 and I² = 40%). The tendency of mean thresholds of PTA was higher in diabetics than in controls, with results being statistically significant at 250, 500 and 1000 Hz. OAE were significantly lower in diabetic patients. ABR latencies were longer in T1D group compared to controls and were statistical significant.

CONCLUSIONS

Patients with T1D have a significantly greater prevalence of HL compared to the control group. These damages could be compared to other microvascular diseases. Further studies are needed to assess whether hearing testing should be considered as a part of the screening process in T1D patients and therefore, secondary preventive treatment may be warranted as well.

Association between self-reported hearing impairment and diabetes: a Brazilian population-based study: Association between self-reported hearing impairment and diabetes in adults

BACKGROUND

Some studies have already explored the relationship between diabetes and hearing loss; however, this relationship has still not been well established, especially due to methodological limitations related to lack of control for confounders. The aim of this study was to analyze the association between self-reported hearing impairment and diabetes among adults in Brazil, controlling for sociodemographic and occupational exposure to ototoxic agents.

METHODS

This is a cross-sectional study based on data collected by the National Health Survey of 2013 in Brazil. A total of 60,202 individuals aged≥18 years were interviewed. Crude and adjusted prevalence ratios were calculated using the Poisson regression model with robust estimation of the variance. All analyzes were performed considering the appropriated weights imposed by the complex sample design.

RESULTS

Hearing loss prevalence was 2.56% (95%CI: 2.34-2.79). It was higher in males, older age groups, white and individuals with lower levels of schooling. Diabetes was positively and significantly associated with hearing loss in the crude analysis (PRcrude = 2.92; 95%CI: 2.75-3.11) and also in the analysis adjusted for gender, age, skin color, schooling, smoking, alcohol consumption and occupational exposure (PRadj = 1.46; 95%CI: 1.32-1.61).

CONCLUSIONS

The present results suggest that individuals with diabetes have higher prevalence of hearing impairment. There is the need of longitudinal studies to investigate if diabetes is a risk factor to hearing impairment.

Association between diabetes mellitus and hearing impairment in American and Korean populations

AIMS

The aim of this study was to evaluate ethnic- and sex-specific associations between DM and hearing impairment.

METHODS

For this cross-sectional study using National Health and Nutrition Examination Survey in the U.S. and Korea, the total number of eligible participants included was 7081 in the U.S. and 15,704 in Korea. Hearing impairment was defined as a pure tone threshold level ≥ 25 dB. Multivariate logistic regression analysis was conducted, adjusting for age, sex, race/ethnicity, socioeconomic status, body mass index, noise exposure, smoking, hypertension, and dyslipidemia.

RESULTS

The association between DM and hearing impairment was found to be sex-specific. The multivariate adjusted ORs of high-frequency impairment were 0.843 (95% CI, 0.524-1.356) in American men, and 1.073 (95% CI, 0.835-1.379) in Korean men, while the ORs in women from U.S. and Korea were 1.911 (95% CI, 1.244-2.935) and 1.421 (95% CI, 1.103-1.830), respectively. A subgroup analysis of each race/ethnicity among the U.S. adults showed similar results. In contrast to high-frequency impairment, there was no significant association between low-frequency impairment and DM in both men and women.

CONCLUSION

Our results suggest that DM is associated with hearing impairment in only women, irrespective of race/ethnicity groups.

Alteration of auditory function in type 2 diabetic and pre-diabetic patients

BACKGROUND

The association between type 2 diabetes mellitus (T2DM) and hearing loss has not been fully investigated and there is little information on the effects of pre-diabetes on alterations in auditory function in Chinese subjects.

METHODS

The study recruited 51 patients with T2DM, 55 patients with pre-diabetes and 43 control subjects. Auditory function was assessed by pure tone audiometry (PTA) tests and distortion product of otoacoustic emissions (DPOAEs). Tinnitus symptoms were recorded using a medical history questionnaire.

RESULTS

A significantly larger number of patients with T2DM (45.1%) were affected by hearing loss, compared to pre-diabetes patients (23.6%; p = .04) and control subjects (25.6%; p = .02), as assessed by PTA. There was no significant difference in PTA between the number of pre-diabetes patients and control subjects. In contrast, mean DPOAEs amplitudes of the pre-diabetes patients were significantly lower than of the control subjects, at all frequencies investigated, except 0.75 kHz. A significantly greater number of pre-diabetes patients reported tinnitus symptoms.

CONCLUSIONS

Diabetes is associated with bilateral sensorineural hearing loss, especially at high frequencies. While pre-diabetes is not necessarily associated with significant hearing loss, there may be cochlear malfunction, as indicated by DPOAEs. Thus, patients with pre-diabetes who have tinnitus may benefit from DPOAEs and PTA tests.

Diabetes mellitus and the incidence of hearing loss: a cohort study

Background

To evaluate the association between diabetes mellitus (DM) and the development of incident hearing loss.

Methods

Prospective cohort study was performed in 253 301 adults with normal hearing tests who participated in a regular health-screening exam between 2002 and 2014. The main exposure was the presence of DM at baseline, defined as a fasting serum glucose ≥ 126 mg/dL, a self-reported history of DM or current use of anti-diabetic medications. Pre-diabetes was defined as a fasting glucose 100-125 mg/dL and no history of DM or anti-diabetic medication use. Incident hearing loss was defined as a pure-tone average of thresholds at 0.5, 1.0 and 2.0 kHz > 25 dB in both right and left ears.

Results

During 1 285 704 person-years of follow-up (median follow-up of four years), 2817 participants developed incident hearing loss. The rate of hearing loss in participants with normal glucose levels, pre-diabetes and DM were 1.8, 3.1 and 9.2 per 1000 person-years, respectively ( P < 0.001). The multivariable-adjusted hazard ratios for incident hearing loss for participants with pre-diabetes and DM compared with those with normal glucose levels were 1.04 (95% confidence interval 0.95-1.14) and 1.36 (1.19-1.56), respectively. In spline regression analyses, the risk of incident hearing loss increased progressively with HbA1c levels above 5%.

Conclusions

In this large cohort study of young and middle-aged men and women, DM was associated with the development of bilateral hearing loss. DM patients have a moderately increased risk of future hearing loss.

Interaction between diabetes mellitus and hypertension on risk of hearing loss in highly endogamous population

AIM

The aim of this study was to determine the prevalence of hearing loss and its association with type 2 diabetes mellitus (T2DM) in a highly endogamous population.

DESIGN

This is a cross-sectional study.

SETTING

The present study is carried out in Ear Nose Throat (ENT) and Endocrinology outpatient clinics of the Hamad General and Rumeilah Hospitals, Hamad Medical Corporation.

SUBJECTS

All subjects aged between 20 and 59 years who visited the Endocrinology and ENT outpatient clinics of the Hamad Medical Corporation with hearing difficulty were included in this study during the period from January 2013 to July 2014.

METHOD

During the study period, prevalence, hearing, audiological test, family history and medical problems associated with hearing impairment in middle aged patients were recorded. Two audiometers Grason Stadler GSI 61 and Madsen Orbiter 922 were used to evaluate the hearing loss.

RESULT

Majority of the hearing loss observed at the age above 45 years old, (44.8% vs 51.7%, p=0.05). The prevalence of hearing impairment was higher in Qataris than in non-Qataris (59.7% vs 46.6%, p<0.001). The consanguineous marriages were observed higher in Hearing loss (32.1%) than in normal hearing (21.8%) (p=0.028). The mean of diabetes onset duration (7.8±4.12years), sleeping disorder (5.81±1.29h), obese subjects (38% vs 27.4%); family history of diabetes (30.6 vs 23.1%) were higher among hearing impairment. The associated risk factors were significantly higher in T2DM with hearing loss, hypoglycemia (32.8% vs 27.4%), retinopathy (313% vs 18.5%), Nephropathy (17.9% vs 9.8%), Neuropathy (17.9% vs 10.2%), macro-vascular disease (11.9% vs 6.2%), diabetic foot ulcer (20.9% vs 12.6%), Tinnitus (68.7% vs 51.3%), and Vertigo (25.4% vs 16.9%) than in normal hearing diabetes. There was a statistically significant differences between hearing impairment and normal hearing among T2DM regarding hearing assessment frequency (p=0.041). There were statistically significant differences between hearing impairment versus normal hearing for vitamin D [18.91±7.65ng/mL vs 22.85±9.00ng/mL; p<0.001], calcium [1.80±0.12ng/mL vs 1.96±0.14mmol/L; p<0.001], magnesium [0.80±0.09mmol/L vs 0.8±0.14mmol/L; p<0.001], phosphorous [1.42±0.30mmol/L vs 1.56±0.26mmol/L; p<0.001], ceatinine [1.42±0.30mmol/L vs 1.56±0.26mmol/L; p<0.001], cholesterol [4.92±1.08mmol/L vs 4.40±1.01mmol/L; p=0.035], LDL [1.92±0.88mmol/L vs 2.09±0.92mmol/L; p=0.024], albumin [43.1±6.10mmol/L vs 39.8±7.93mmol/L; p=0.010], systolic blood pressure [135.8±16.6Hg vs 130.2±12.5Hg; p=0.017] and, diastolic blood pressure [85.1±9.2mmHg vs 83.0±7.9mmHg; p=0.012]. There were highly statistically significant differences between hearing impairment versus normal for both side right and left ear frequency in Db unit (p<0.001). The multivariate stepwise logistic regression analysis revealed that head ache (p<0.001), family history of DM (p<0.001), sleep disturbance (p<0.001), high blood pressure (p=0.006), consanguinity (p=0.010), nationality (p=0.014), age in years (p=0.025), and sheesha smokers (p=0.045) were considered at higher risk as a predictors of hearing loss among diabetic patients.

CONCLUSION

The current study results confirm previous reports that adults with DM and hypertension associated showed greater hearing impairment in highly endogamous population… Diabetic patients with hearing loss were likely to have high blood glucose and other risk factors like hypertension, retinopathy, nephropathy and neuropathy.

Vascular and Neuroepithelial Histopathology of the Saccule in Humans With Diabetes Mellitus

HYPOTHESIS

This study aimed to determine if there are quantitative differences in the neuroepithelium and microvasculature of the saccule between subjects with and without diabetes mellitus (DM).

BACKGROUND

Histopathologic changes that may underlie the association between DM and vestibular dysfunction have not been characterized in humans.

METHODS

Human temporal bones (HTBs) from 39 subjects with DM (n = 16 type I DM [T1DM], n = 23 type II DM [T2DM]) were compared with 40 group age-matched controls. Vessel wall thickness was measured from the saccular arteriole. Type I and type II vestibular hair cell (VHC) counts were performed on perpendicularly oriented saccular maculae using differential interference contrast microscopy (T1DM: 5HTB/3 subjects; T2DM: 9HTB/8 subjects; controls: 25HTB/20 subjects).

RESULTS

The mean density of type I VHCs was 16 to 17% lower in the DM groups compared to controls (T1DM 52.21 [4.26], T2DM 53.3 [5.34], control 63.14 [2.49] cells/mm, p = 0.02). There were no differences between T1DM, T2DM, and control groups in type II VHC density (T1DM 40.89 [5.17], T2DM 40.44 [6.93], control 42.80 [1.79] cells/mm, p = 0.92) or in mean vessel wall thickness (T1DM 2.23 [0.62], T2DM 2.18 [0.53], control 2.00 [0.53] μm, p = 0.26).

CONCLUSION

Neuroepithelial pathology, manifested as lower density of type I VHCs, was observed in the saccules of subjects with DM. Saccular microangiopathy, expressed as alterations in arteriole thickness, was not observed. These findings are consistent with histologic observations in animals with experimentally induced diabetes. DM may have a selective and deleterious effect on human vestibular sensory epithelia.

An association of type 1 diabetes mellitus with auditory dysfunction: A systematic review and meta-analysis

OBJECTIVE

To establish the relationship between the presence of type 1 diabetes mellitus (DM) and auditory dysfunction in clinical settings by a systematic review and meta-analysis of currently available published data.

DATA SOURCES AND REVIEW METHODS

The electronic databases PubMed, Embase, and Wanfang Data were searched for eligible relevant studies up to May 2016, and the reference lists of the retrieved articles were used for additional manual search. All the articles included in this pooled analysis were determined according to the preset inclusion and exclusion criteria. Meta-analysis of pooled data was performed using Review Manager 5.3.

RESULTS

A total of 15 studies were included for further combined analysis. The results showed that patients with type 1 diabetes had a significantly higher prevalence of hearing loss than controls (odds ratio = 49.08, 95% confidence interval = 12.03-200.31, P < 0.00001); standardized mean of differences (SMD) of pure tone audiometry at 4,000 Hz between diabetes and controls was 0.87 (Z = 2.22, P = 0.03, I2 = 95%); SMD of the latency time was 0.54 (Z = 2.69, P = 0.007, I2 = 78%) for waves III and 0.61 (Z = 2.38, P = 0.02, I2 = 86%) for wave V, respectively; and SMD of the interpeak latency time was 0.41 (Z = 2.84, P = 0.005, I2 = 39%) for waves I to III and 0.61 (Z = 2.67, P = 0.008, I2 = 81%) for waves I to V, respectively, between diabetics and controls.

CONCLUSION

Our study reveals that there is relationship between the presence of type 1 DM and an increased risk for developing mild and subclinical hearing impairment.

LEVEL OF EVIDENCE

NA. Laryngoscope, 127:1689-1697, 2017.

A narrative review of obesity and hearing loss

The comorbidities related to obesity are already extensive, but as the prevalence of obesity increases globally, so do the number of its associated conditions. The relationship between hearing impairment and obesity is a relatively recent research interest, but is significant as both conditions have the ability to substantially reduce an individual's quality of life both physically and psychologically. Obesity has a significant effect on vascular function, and this may have an impact on highly vascular organs such as the auditory system. This review aims to provide an overview of the existing literature surrounding the association between hearing loss and obesity, in order to emphasise these two highly prevalent conditions, and to identify areas of further investigation. Our literature search identified a total of 298 articles with 11 articles of relevance to the review. The existing literature in this area is sparse, with interest ranging from obesity and its links to age-related hearing impairment (ARHI) and sudden sensorineural hearing loss (SSNHL), to animal models and genetic syndromes that incorporate both disorders. A key hypothesis for the underlying mechanism for the relationship between obesity and hearing loss is that of vasoconstriction in the inner ear, whereby strain on the capillary walls due to excess adipose tissue causes damage to the delicate inner ear system. The identified articles in this review have not established a causal relationship between obesity and hearing impairment. Further research is required to examine the emerging association between obesity and hearing impairment, and identify its potential underlying mechanisms.

Early detection of hearing impairment in patients with diabetes mellitus with otoacoustic emission. A systematic review and meta-analysis

CONCLUSIONS

The distortion product otoacoustic emission (DPOAE) amplitudes in diabetics were significantly lower than those in controls when pure tone audiometry (PTA) was within normal limits, implying cochlear function impairment in the early stage of diabetes mellitus. Retrocochlear damage was suggested by elongated wave latencies and the wave interval of auditory brainstem response (ABR) in diabetics.

OBJECTIVES

This study aimed to systematically analyze the application of DPOAE in evaluation of the hearing function of diabetics.

DATA SOURCES AND REVIEW METHODS

Eligible articles were identified through searches of nine different electronic databases. Two investigators reviewed the original articles independently, with pre-defined inclusion and exclusion criteria. Meta-analyses were conducted by using Metan module.

RESULTS

There were seven articles eligible for the analysis. PTA thresholds were within normal limits in all diabetics at low-middle frequencies. The mean DPOAE amplitudes of diabetics were significantly lower than those of controls. The standardized mean difference (SMD) (95% CI) was -0.49 (-0.70, -0.27), -0.46 (-0.63, -0.30), and -0.60 (-0.77, -0.43) at 1, 2, and 4 kHz, respectively. The latencies of waves I, III, and V in diabetes were significantly longer than those of controls (0.43 (0.23, 0.64), 0.54 (0.33, 0.75), and 0.56 (0.35, 0.77), respectively). The wave interval I-V was significantly longer in diabetics (p < .001, 0.47 [0.24, 0.70]).

Diabetes mellitus and sensorineural hearing loss: is there an association? Baseline of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

OBJECTIVES:

Although several studies have investigated the effects of diabetes on hearing loss, the relationship between these two conditions remains unclear. Some studies have suggested that diabetes may cause sensorineural hearing loss, whereas others have failed to find an association. The biggest challenge in investigating the association between diabetes and hearing loss is the presence of confounding variables and the complexity of the auditory system. Our study investigated the association between diabetes and sensorineural hearing loss. We evaluated the influence of time from diabetes diagnosis on this association after controlling for age, gender, and hypertension diagnosis and excluding those subjects with exposure to noise.

METHODS:

This cross-sectional study evaluated 901 adult and elderly Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) participants from São Paulo, Brazil who underwent audiometry testing as part of ELSA-Brasil's baseline assessment.

RESULTS:

Hearing thresholds and speech test results were significantly worse in the group with diabetes than in the group without diabetes. However, no significant differences were found between participants with and without diabetes after adjusting for age, gender, and the presence of hypertension. Hearing thresholds were not affected by occupational noise exposure in the groups with and without diabetes. In addition, no association between the duration of diabetes and hearing thresholds was observed after adjusting for age, gender, and hypertension.

CONCLUSION:

We found no association between the duration of diabetes and worse hearing thresholds after models were adjusted for age, gender, and the presence of hypertension.

A Retrospective Examination of the Effect of Diabetes on Sensory Processing in Older Adults

PURPOSE

The purpose of this article is to examine retrospectively the impact of diabetes mellitus on auditory, visual, and tactile processing in older adults.

METHOD

Fourteen (10.4%) of a sample of 135 older adults self-reported the presence of diabetes mellitus in a study of sensory and cognitive processing across the adult lifespan. In this study, the performance of the subgroup with diabetes on a number of psychophysical sensory-processing measures was compared with that of the 121 older adults without diabetes. Measures of sensory processing focused on temporal processing and threshold sensitivity in each of 3 sensory modalities: hearing, vision, and touch.

RESULTS

The subgroup of older adults with diabetes differed significantly (p < .05) from the larger group without diabetes only for measures of auditory temporal-order and temporal-masking identification tasks.

CONCLUSION

This retrospective study provides additional evidence in support of higher level auditory-processing deficits in older adults with a positive history of diabetes mellitus.

A study of hearing function and histopathologic changes in the cochlea of the type 2 diabetes model Tsumura Suzuki obese diabetes mouse

OBJECTIVES

This study used Tsumura Suzuki Obese Diabetes (TSOD) mice as a spontaneous type 2 diabetes model and Tsumura Suzuki Non-obesity (TSNO) mice as controls to investigate factors involved in the onset of hearing impairment.

METHOD

Body weight, blood glucose levels, and auditory brainstem responses (ABRs) were measured. The cochleae were excised and evaluated histopathologically.

RESULTS

The TSOD mice showed significant hyperglycemia at 2-7 months and severe obesity at 5-10 months; significantly elevated ABR thresholds at 8-10 months; and the capillary lumens in the cochlea stria vascularis were narrower in the TSOD mice than in the TSNO mice. At 17 months, India ink vascular staining of the TSOD mice's cochleae revealed decreased capillary density in the stria vascularis. The vascular area of capillaries in the stria vascularis and the vascular area were significantly smaller in TSOD mice. Histopathological analysis showed vessel wall thickening in the modiolus and narrowed capillaries in the stria vascularis, suggesting reduced blood flow to the inner ear.

CONCLUSION

The diabetes mice model used in our study showed early age-associated hearing loss, and histopathology showed findings of vessel wall thickening in the modiolus, narrowing of capillaries in the stria vascularis, and chronically reduced blood flow in the cochlea.

Características audiológicas de pacientes com diabetes mellitus Tipo 2

RESUMO Objetivos: identificar as características audiológicas de pacientes com diabetes mellitus tipo 2. Métodos: estudo transversal, realizado em unidade de atenção secundária para diabetes em Fortaleza, de abril a julho de 2010. Amostra composta por 152 pacientes diabéticos tipo 2, independente do sexo, entre 36 e 60 anos. Realizou-se audiometria tonal liminar (ATL), emissões otoacústicas evocadas por estímulo transiente (EOAT) e emissões otoacústicas evocadas-produto de distorção (EOAPD). Resultados: associação da idade e do tempo de diagnóstico com a presença de perda auditiva, e do tempo de diagnóstico com a ausência de EOAPD. Observou-se perda auditiva sensorioneural em 63,2% dos pacientes, das quais 71,9% eram bilaterais e 75% simétricas. Aproximadamente, 50% das perdas auditivas apresentaram configuração plana. As EOAT estavam ausentes em 75% dos pacientes e as EOAPD em 78,9%. Houve ausência de emissões otoacústicas na presença de ATL normal, em média, em 32% dos pacientes à direita e 48% à esquerda. Já a presença de emissões otoacústicas na ocorrência de perda auditiva foi observada em, aproximadamente, 30% dos pacientes para EOAT e 14% para EOAPD à direita; e 25% para EOAT e 11% para EOAPD à esquerda. Conclusão: predomínio de perda auditiva sensorioneural bilateral simétrica com configuração plana, e ausência de EOAT e EOAPD. A análise da associação dos resultados da ATL e das emissões otoacústicas sugere prejuízo das células ciliadas externas da cóclea ou possível neuropatia auditiva. Tais achados justificariam o monitoramento da audição destes pacientes, bem como a realização de testes específicos para avaliação do sistema auditivo central.

Multimorbidity in the community-dwelling elderly in urban China

OBJECTIVES

The primary objective of the study was to investigate the prevalence and patterns of multimorbidity in the community-dwelling elderly in urban China.

METHODS

By a cluster random sampling method, 2452 persons aged 60 years and older were enrolled as the subjects in an urban community in Nanjing, China. Data on 13 chronic diseases were collected by interviews, physical check-ups and support by physicians. Factor analyses and the logistic regression models were performed to analyze the patterns of multimorbidity.

RESULTS

The prevalence of multimorbidity was 49.4% in the community-dwelling elderly in urban China. The observed prevalence of 6 chronic disease pairs was higher than their expected prevalence, including hypertension and diabetes, hypertension and coronary heart disease, hypertension and dyslipidaemia, diabetes and cataract, diabetes and hearing disorder, hypertension and stroke. Three patterns were detected as follows: the first pattern with a prevalence of 9.5% covered degenerative diseases (hearing disorder, cataract, joint disease) and cancer; The second pattern with a prevalence of 1.7% was characterized by liver disease, lung disease, gastrointestinal disease; And the third pattern with a prevalence of 22.4% was characterized by cardiovascular diseases (dyslipidaemia, hypertension, coronary heart disease), metabolic diseases (diabetes) and kidney disease. Compared with <70 years, ≥80 years were found as the risk factor of the prevalence of three patterns.

CONCLUSION

A significant proportion of elderly populations was affected by multimorbidity in urban China. Specific patterns of multimorbidity were found at group level and the prevalence was associated with age.

Cochlear, auditory brainstem responses in Type 1 diabetes: relationship with metabolic variables and diabetic complications

AIMS

Few studies have analysed the presence of hearing abnormalities in diabetes. We assessed the presence of subclinical auditory alterations and their possible association with early vascular and neurological dysfunction in young adults with Type 1 diabetes of long duration.

METHODS

Thirty-one patients with Type 1 diabetes (mean age 33 ± 2.3 years, disease duration 25.7 ± 4.2 years) and 10 healthy controls underwent pure tone audiometry (PTA), distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) analyses. Associations with metabolic variables and chronic complications were explored.

RESULTS

Compared with healthy controls, patients with diabetes had significantly higher mean hearing thresholds, although still within the normoacusic range. DPOAE intensities at medium frequencies (2.8-4 kHz) were significantly lower in patients with diabetes. In ABR, in addition to waves I, III and V, we observed the appearance of a visible wave IV in patients with diabetes compared with controls (prevalence 61% vs. 10%, P < 0.05), and its appearance was related to a prolonged I-V interval (4.40 ± 0.62 ms vs. 4.19 ± 0.58 ms, P < 0.05). Diastolic blood pressure was higher in people with abnormal DPOAE (P < 0.05), whereas systolic blood pressure correlated with wave V and interpeak I-V interval latencies. A trend towards an association between evidence of wave IV and the presence of somatic neuropathy or abnormal cardiovascular autonomic tests was observed.

CONCLUSIONS

Young adults with long-term Type 1 diabetes have subclinical abnormalities in qualitative auditory perception, despite normal hearing thresholds, which might reflect neuropathic and/or vascular alterations.

Type 2 Diabetes and Hearing Impairment

Hearing impairment (HI) and type 2 diabetes are both highly prevalent disabling conditions. Type 2 diabetes has been modestly associated with a higher likelihood of HI in many, but not all, population-based studies, with stronger associations found in studies that included younger age groups. Pathophysiologic studies suggest that persons with diabetes are predisposed to HI in the higher frequencies. Proposed mechanisms underlying the association between diabetes and HI include the combined contributions of hyperglycemia and oxidative stress to cochlear microangiopathy and auditory neuropathy. In this review, we highlight recent population-based studies of type 2 diabetes and HI and examine evidence for diabetes-induced pathophysiologic changes that may result in damage to the auditory system.

Diabetes-Associated Changes in Cortical Auditory-Evoked Potentials in Relation to Normal Aging

OBJECTIVES

(1) To characterize the influence of type 2 diabetes mellitus (DM) on cortical auditory-evoked potentials (CAEPs) separate from the effects of normal aging, and (2) to determine whether the disease-related effects are modified by insulin dependence.

DESIGN

A cross-sectional study was conducted in a large cohort of Veterans to investigate the relationships among type 2 DM, age, and CAEPs in randomly selected participants with (N = 108) and without (N = 114) the disease and who had no more than a moderate hearing loss. Participants with DM were classified as insulin-dependent (IDDM, N = 47) or noninsulin-dependent (NIDDM, N = 61). Other DM measures included concurrent serum glucose, HbA1c, and duration of disease. CAEPs were evoked using a passive homogeneous paradigm (single repeating stimulus) by suprathreshold tones presented to the right ear, left ear, or both ears. Outcome measures were adjusted for the pure-tone threshold average for frequencies of 0.5, 1, and 2 kHz and analyzed for differences in age effects between participant groups using multiple regression.

RESULTS

There is little variation across test ear conditions (left, right, binaural) on any CAEP peak in any of the groups. Among no-DM controls, P2 latency increases about 9 msec per decade of life. DM is associated with an additional delay in the P2 latency of 7 and 9 msec for the IDDM and NIDDM groups, respectively. Moreover, the slope of the function relating P2 latency with age is similar across participant groups and thus the DM effect appears constant across age. Effects on N1 latency are considerably weaker, with age effects of less than 4 msec per decade across all groups, and DM effects of only 2 (IDDM) or 3 msec (NIDDM). In the NIDDM group, the slope relating N1 latency to age is steeper relative to that observed for the no-DM group, providing some evidence of accelerated "aging" for this CAEP peak. DM does not substantially reduce N1-P2 amplitude and age relationships with N1-P2 amplitude are effectively absent. There is no association between pure-tone average at 0.5, 1, and 2 kHz and any aspect of CAEPs in this cohort.

CONCLUSIONS

In a large cohort of Veterans, we found that type 2 DM is associated with prolonged N1 and P2 latencies regardless of whether insulin is required to manage the disease and independent of peripheral hearing thresholds. The DM-related effects on CAEP latencies are threefold greater for P2 compared with N1, and there is little support that at the cortical level, IDDM participants had poorer responses compared with NIDDM participants, although their responses were more variable. Overall, these results indicate that DM is associated with slowed preattentive neural conduction. Moreover, the observed 7 to 9 msec P2 latency delay due to DM is substantial compared with normal age changes in P2, which are 9 msec per decade of life in this cohort. Results also suggest that whereas N1 latency changes with age are more pronounced among individuals with DM versus without DM, there was no evidence for more rapid aging of P2 among patients with DM. Thus, the damage responsible for the major DM-related differences may occur early in the DM disease process. These cross-sectional results should be verified using a longitudinal study design.

Comparison of Various Anthropometric Indices as Risk Factors for Hearing Impairment in Asian Women

Background

The objective of the present study was to examine the associations between various anthropometric measures and metabolic syndrome and hearing impairment in Asian women.

Methods

We identified 11,755 women who underwent voluntary routine health checkups at Yeungnam University Hospital between June 2008 and April 2014. Among these patients, 2,485 participants were <40 years old, and 1,072 participants lacked information regarding their laboratory findings or hearing and were therefore excluded. In total 8,198 participants were recruited into our study.

Results

The AUROC value for metabolic syndrome was 0.790 for the waist to hip ratio (WHR). The cutoff value was 0.939. The sensitivity and specificity for predicting metabolic syndrome were 72.7% and 71.7%, respectively. The AUROC value for hearing loss was 0.758 for WHR. The cutoff value was 0.932. The sensitivity and specificity for predicting hearing loss were 65.8% and 73.4%, respectively. The WHR had the highest AUC and was the best predictor of metabolic syndrome and hearing loss. Univariate and multivariate linear regression analyses showed that WHR levels were positively associated with four hearing thresholds including averaged hearing threshold and low, middle, and high frequency thresholds. In addition, multivariate logistic analysis revealed that those with a high WHR had a 1.347–fold increased risk of hearing loss compared with the participants with a low WHR.

Conclusion

Our results demonstrated that WHR may be a surrogate marker for predicting the risk of hearing loss resulting from metabolic syndrome.

Does gestational diabetes result in cochlear damage?

BACKGROUND

Glucose metabolism has a significant impact on inner-ear physiology. Therefore, hearing may be affected in gestational diabetes.

METHOD

A matched case-control study was performed to evaluate 27 patients with gestational diabetes and 31 non-diabetic pregnant women with similar demographic characteristics. A medical history was taken for each participant, and otological inspections and high-frequency audiometry tests were performed.

RESULTS

There were no significant differences in average pure tone air-bone hearing thresholds between the groups (p > 0.05). However, evaluation of high-frequency hearing thresholds indicated significantly increased auditory thresholds at 10 kHz and 12 kHz for right ears and at 8, 10, 12 and 14 kHz for left ears in the gestational diabetes group (p < 0.001).

CONCLUSION

An investigation into cochlear damage in gestational diabetic patients showed significant high-frequency hearing loss. Further studies are needed to validate these findings in different ethnic groups and geographical populations.

Cardiovascular risk factors and hearing loss: The HUNT study

OBJECTIVE

The purpose of the present paper was to examine the association between prospectively and cross-sectionally assessed cardiovascular risk factors and hearing loss.

DESIGN

Hearing was assessed by pure-tone average thresholds at low (0.25-0.5 kHz), middle (1-2 kHz), and high (3-8 kHz) frequencies. Self-reported or measured cardiovascular risk factors were assessed both 11 years before and simultaneously with the audiometric assessment. Cardiovascular risk factors were smoking, alcohol use, physical inactivity, waist circumference, body mass index, resting heart rate, blood pressure, triglycerides, total serum cholesterol, LDL cholesterol, HDL cholesterol, and diabetes.

STUDY SAMPLE

A population-based cohort of 31 547 subjects.

RESULTS

After adjustment for age, sex, level of education, income, recurrent ear infections, and noise exposure, risk factors associated with poorer hearing sensitivity were smoking, diabetes, physical inactivity, resting heart rate, and waist circumference. Smoking was only associated with hearing loss at high frequencies. The effects were very small, in combination explaining only 0.2-0.4% of the variance in addition to the component explained by age and the other cofactors.

CONCLUSION

This cohort study indicates that, although many cardiovascular risk factors are associated with hearing loss, the effects are small and of doubtful clinical relevance.

Medication Use in Adults with and without Hearing Impairment

The objective of this study was to determine whether hearing ability in adults is associated with medication use in general, the use of specific types of medication, or polypharmacy. In this exploratory study, data of the National Longitudinal Study on Hearing (NL-SH; n = 2,160) were used. In total, 62% of the participants reported using any medication in the past 28 days. Hearing ability in noise, as determined with an online digit-triplet speech-in-noise test, was significantly associated with (1) medication acting on the alimentary tract and metabolism (including diabetes and acid-related disorders), (2) use of calcium blockers, and (3) medication used for sensory organs.

Diabetes and Hearing Loss Among Underserved Populations

Type 2 diabetes (T2DM) disproportionately affects the underserved population, and has been identified as the major risk factor for many microvascular diseases. T2DM also affects the vasculature and neural system of the inner ear, often leading to hearing loss, a major risk factor for falls, depression, and other health problems. This article aims to: increase awareness of the association between T2DM and hearing loss; promote screening for hearing loss; discuss available resources and assistive devices for those with hearing loss; and encourage nurses to take an active role in advocating for assessment and treatment of hearing loss in T2DM patients.

Hearing Impairment in Relation to Severity of Diabetes in a Veteran Cohort

OBJECTIVE

Type 2 diabetes is epidemic among veterans, approaching three times the prevalence of the general population. Diabetes leads to devastating complications of vascular and neurologic malfunction and appears to impair auditory function. Hearing loss prevention is a major health-related initiative in the Veterans Health Administration. Thus, this research sought to identify, and quantify with effect sizes, differences in hearing, speech recognition, and hearing-related quality of life (QOL) measures associated with diabetes and to determine whether well-controlled diabetes diminishes the differences.

DESIGN

The authors examined selected cross-sectional data from the baseline (initial) visit of a longitudinal study of Veterans with and without type 2 diabetes designed to assess the possible differences in age-related trajectories of peripheral and central auditory function between the two groups. In addition, the diabetes group was divided into subgroups on the basis of medical diagnosis of diabetes and current glycated hemoglobin (HbA1c) as a metric of disease severity and control. Outcome measures were pure-tone thresholds, word recognition using sentences presented in noise or time-compressed, and an inventory assessing the self-perceived impact of hearing loss on QOL. Data were analyzed from 130 Veterans ages 24 to 73 (mean 48) years with well-controlled (controlled) diabetes, poorly controlled (uncontrolled) diabetes, prediabetes, and no diabetes. Regression was used to identify any group differences in age, noise exposure history, and other sociodemographic factors, and multiple regression was used to model each outcome variable, adjusting for potential confounders. Results were evaluated in relation to diabetes duration, use of insulin (yes, no), and presence of selected diabetes complications (neuropathy and retinopathy).

RESULTS

Compared with nondiabetics, Veterans with uncontrolled diabetes had significant differences in hearing at speech frequencies, including poorer hearing by 3 to 3.5 dB for thresholds at 250 Hz and in a clinical pure-tone average, respectively. Compared with nondiabetic controls, individuals with uncontrolled diabetes also significantly more frequently reported that their hearing adversely impacted QOL on one of the three subscales (ability to adapt). Despite this, although they also had slightly poorer mean scores on both word recognition tasks performed, these differences did not reach statistical significance and all subjects performed well on these tasks. Compared with Veterans with controlled diabetes, those with uncontrolled disease tended to have had diabetes longer, be insulin-dependent, and have a greater prevalence of diabetic retinopathy. Results are generally comparable with the literature with regard to the magnitude of threshold differences and the prevalence of hearing impairment but extend prior work by providing threshold difference and hearing loss prevalence effect sizes by category of diabetes control and by including additional functional measures.

CONCLUSIONS

In a cohort of Veterans with type 2 diabetes and relatively good hearing, significant effects of disease severity were found for hearing thresholds at a subset of frequencies and for one of the three QOL subscales. Significant differences were concentrated among those with poorly controlled diabetes based on current HbA1c. Results provide evidence that the observed hearing dysfunction in type 2 diabetes might be prevented or delayed through tight metabolic control. Findings need to be corroborated using longitudinal assessments.

The prevalence and factors associated with hearing impairment in the Korean adults: the 2010-2012 Korea National Health and Nutrition Examination Survey (observational study)

There are few studies that have used audiometric testing to gauge the demographic characteristics and associated risk factors for hearing loss at the national-level. Here, we investigated the weighted prevalence and associated factors of hearing impairment in 16,040 Korean adult population. Subjects completed audiometric test and laboratory examination as part of the data from The 2010-2012 Korea National Health and Nutrition Examination Survey (KNHANES). In our respective study, the overall weighted (n = 33,762,584) prevalence of mild hearing impairment among the Korean adult population was 20.5% (95% clearance [CI], 19.6-21.6), whereas moderate-to-profound hearing impairment was 9.2% (95% CI, 8.6-9.9). The weighted prevalence of mild hearing impairment in younger adults (19-39 years' old) was 4.4% (3.5-5.5), in middle-age adults (40-64 years), it was 21.1% (19.8-22.5), and in older adults (≥65 years' old), it was 69.7% (67.8-71.6). Logistic regression analyses were performed for low/mid frequency or high-frequency mild hearing impairment with age, sex, tobacco use, heavy alcohol use, educational background, occupational noise exposure, obesity, hypertension, diabetes, total serum cholesterol, and estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m² as covariates. The analyses revealed independent correlations between increased age, tobacco use, education, hypertension, and eGFR <60 mL/min/1.73m², and low/mid frequency and high frequency mild hearing impairment. High frequency mild hearing impairment was positively correlated with male sex, diabetes, and an increase in total serum cholesterol. Taken together, hearing impairment in Korea is highly prevalent with approximately one-fifth of Korean adult reporting mild hearing impairment. This study suggests that individuals with cardiovascular risk factors such as hypertension, diabetes, smoking, increased serum cholesterol, or decreased eGFR are at particular risk of developing hearing impairment. As such, these groups may benefit from hearing loss screening in addition to those groups typically considered to be of elevated risk including geriatrics, those of low socioeconomic status, and those with considerable occupational noise exposure.

Atherogenic risk factors and hearing thresholds

The objective of this study was to evaluate the influence of atherogenic risk factors on hearing thresholds. In a cross-sectional study we analyzed data from a Danish survey in 2009-2010 on physical and psychological working conditions. The study included 576 white- and blue-collar workers from children's day care units, financial services and 10 manufacturing trades. Associations between atherogenic risk factors (blood lipids, glycosylated hemoglobin, smoking habits, body mass index (BMI), and ambulatory blood pressure) and hearing thresholds were analyzed using multiple linear regression models. Adjusted results suggested associations between smoking, high BMI and triglyceride level and low high-density lipoprotein level and increased low-frequency hearing thresholds (average of pure-tone hearing thresholds at 0.25, 0.5 and 1 kHz). Furthermore, an increasing load of atherogenic risk factors seemed associated with increased low-frequency hearing thresholds, but only at a borderline level of statistical significance. Associations were generally strongest with hearing levels of the worst hearing ear. We found no statistically significant associations between atherogenic risk factors and high-frequency hearing thresholds (average of pure-tone hearing thresholds at 4, 6 and 8 kHz).

Severity of hearing impairment is positively associated with urine albumin excretion rate in patients with type 2 diabetes

Aims/Introduction

To identify risk factors for hearing impairment among patients with type 2 diabetes mellitus.

Methods and Materials

A total of 68 patients with type 2 diabetes were enrolled between March and September of 2011. Pure-tone auditory tests were carried out for each patient at the following speech frequencies: 250; 500; 1,000; 2,000; 4,000 and 8,000 Hz. Participants were classified as having hearing impairment if the average of the pure-tone thresholds measured at 500, 1000 and 2000 Hz in either ear exceeded 25 dBHL. Demographic, anthropometric, clinical, and laboratory parameters and diabetes-associated complications were analyzed.

Results

Patients were divided into those with (n = 32) and without (n = 36) hearing impairment. Hearing impaired participants had a higher urine albumin-to-creatinine ratio than those without (223.1 vs 56.5 mg/g, respectively). After adjustment for age, sex and other risk factors, the urine albumin-to-creatinine ratio remained significantly associated with hearing impairment (odds ratio 9.07, 95% confidence interval 1.73–47.43, P = 0.009). There were no significant differences in oxidative stress between the two groups.

Conclusions

The present study showed increased albuminuria was positively associated with the severity of hearing impairment among patients with type 2 diabetes. Screening for hearing impairment in diabetic patients who develop albuminuria might provide early detection of hearing impairment.