Hearing thresholds in insulin-dependent diabetic patients

Subclinical Auditory Neural Deficits in Patients With Type 1 Diabetes Mellitus

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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.

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.

Hearing thresholds in adult Nigerians with diabetes mellitus: a case-control study

OBJECTIVES

To determine the prevalence, types and severity of hearing loss and associated factors in a hospital population of adult Nigerians with diabetes mellitus.

SUBJECTS AND METHODS

This study was a prospective hospital-based study conducted at the Otorhinolaryngology and Diabetic Clinics of the University of Nigeria Teaching Hospital (UNTH) Ituku-Ozalla, Enugu, for a period of 12 months. Consecutively presenting eligible adult diabetics and their age- and sex-matched healthy controls were recruited. Each case and control participant had clinical and otologic examination, followed by pure tone audiometry. Data were analyzed using descriptive and comparative statistics.

RESULTS

There were 224 patients and 192 control participants. The patients comprised 112 males and 112 females (sex ratio=1:1), whose mean age was 47.6 years (range: 26-80 years). The prevalence of hearing loss was 46.9%. This comprised 43.8% sensorineural and 3.1% conductive hearing losses. The distribution of hearing loss by severity was mild 25.0%, moderate 15.6% and severe 6.3%. The controls comprised 96 males and 96 females whose mean age was 44.6 years (range: 25-79 years). The prevalence of hearing loss was significantly higher overall and by type (sensorineural hearing loss, conductive hearing loss) in cases compared with controls.

CONCLUSION

The prevalence of hearing loss among diabetic adults at UNTH, Enugu, is comparatively high. Hearing loss is predominantly sensorineural and often mild to moderate in severity. Routine audiometric evaluation of all adult diabetics at UNTH is recommended.

Speech perception performance of subjects with type I diabetes mellitus in noise

Introduction

Diabetes mellitus (DM) is a chronic metabolic disorder of various origins that occurs when the pancreas fails to produce insulin in sufficient quantities or when the organism fails to respond to this hormone in an efficient manner.

Objective

To evaluate the speech recognition in subjects with type I diabetes mellitus (DMI) in quiet and in competitive noise.

Methods

It was a descriptive, observational and cross-section study. We included 40 participants of both genders aged 18–30 years, divided into a control group (CG) of 20 healthy subjects with no complaints or auditory changes, paired for age and gender with the study group, consisting of 20 subjects with a diagnosis of DMI. First, we applied basic audiological evaluations (pure tone audiometry, speech audiometry and immittance audiometry) for all subjects; after these evaluations, we applied Sentence Recognition Threshold in Quiet (SRTQ) and Sentence Recognition Threshold in Noise (SRTN) in free field, using the List of Sentences in Portuguese test.

Results

All subjects showed normal bilateral pure tone threshold, compatible speech audiometry and “A” tympanometry curve. Group comparison revealed a statistically significant difference for SRTQ (p = 0.0001), SRTN (p < 0.0001) and the signal-to-noise ratio (p < 0.0001).

Conclusion

The performance of DMI subjects in SRTQ and SRTN was worse compared to the subjects without diabetes.

Clinical Study to Evaluate the Association Between Sensorineural Hearing Loss and Diabetes Mellitus in Poorly Controlled Patients Whose HbA1c >8

The relationship between sensorineural hearing loss (SNHL) and Diabetes mellitus has been known since more than 150 years. The pathophysiology of diabetes related hearing loss is speculative. Hearing loss is usually, bilateral, gradual onset, affecting higher frequencies. This study aims at knowing the prevalence of SNHL in DM and its relation to age, sex, duration of DM and control of DM. A total of 50 type 2 diabetics of age group 30-65 years were involved in the study. FBS, PPBS, HbA1c of all the subjects were done and later subjected to PTA. The type and severity of hearing loss was noted. Occurrence of SNHL was later compared with age, sex, duration, and control of DM. Sensorineural hearing loss was found in 66 % of type II diabetic patients and 34 % were found normal. Out of 50 diabetes mellitus patients, 33 patients had SNHL. All cases of SNHL detected were of gradual in onset and no one had hearing loss of sudden onset. Normal hearing was found in 34 % of patients, whereas 54 % of patients had mild hearing loss and 12 % of patients had moderate hearing loss. Association of hearing loss of DM patients with sex of the patient is insignificant. However there is significant association between older age group, longer duration and uncontrolled DM with that of SNHL. In subjects with HbA1c more than 8 and duration of diabetes mellitus more than 10 years prevalence of SNHL is more than 85 %, which is statistically significant. Sensorineural hearing loss in diabetes mellitus is gradually progressive involving high frequency thresholds. Hearing threshold increases with increasing age duration of diabetes and also high level of HbA1c greater than 8 %.

Increased prevalence of early cochlear damage in young patients with type 1 diabetes detected by distortion product otoacoustic emissions

OBJECTIVE

To evaluate the hearing of adolescents with diabetes mellitus type 1(DM1) by otoacoustic emissions (OAEs), and by comparing different tests with pure-tone audiometry to identify potential early cochlear impairments.

DESIGN

Pure-tone audiometry, transient evoked otoacoustic emissions (TEOAEs), and distortion product otoacoustic emissions (DPOAEs) were performed in a group of adolescents with and without DM1. Clinical characteristics, disease duration, and glycated haemoglobin levels were studied.

STUDY SAMPLE

Participants were 40 adolescents with DM1 and 40 healthy subjects.

RESULTS

Sensorineural hearing loss, affecting frequencies of 6000 and 8000 Hz, was found only in DM1 subjects when compared to the controls (7.7% vs. 0%, p < 0.05). A higher prevalence of cochlear damage was detected by DPOAE responses, 32% belonging from the diabetic group, vs. 3.7% in the control group. Absent TEOAE responses were observed in only three individuals, all from the diabetic group (5.1% of the tests performed in the diabetic group). Additionally, hearing thresholds were better in diabetic subjects with good control when compared to ones with regular or poor control (p = 0.00). Hearing thresholds were higher in poorly controlled diabetics when compared to subjects with good (p = 0.000) or regular control (p = 0.006).

CONCLUSION

Early evidence of cochlear damage was detected in adolescents with DM1 leading to hearing loss at high frequencies. Abnormal DPOAEs responses were found more frequently than the alterations in TEOAEs and pure-tone audiometry, suggesting that DPOAEs evaluation is the most sensitive and it could be used for monitoring the progression of cochlear damage during the early stages of hearing impairment.

Pentoxifylline response in alloxan-induced diabetic rats

CONCLUSION

This study in rats shows that pentoxifylline may reverse detrimental effects of diabetes mellitus (DM) on the auditory system.

OBJECTIVE

To investigate whether delayed auditory brainstem responses (ABRs) induced by DM improve following pentoxifylline treatment in rats.

MATERIALS AND METHODS

Baseline ABRs were recorded in 25 ears of 13 normal-hearing rats. DM was induced by a single injection of alloxan (75 mg/kg of body weight) in all rats. Following a 1-month diabetic period, ABRs were recorded in six diabetic rats. Then, pentoxifylline treatment was administered for 6 weeks (20 mg/kg in drinking water), and final ABR testing was performed. Absolute latencies of waves I, III and V, and inter-peak latency differences (IPL) of I-V were measured in each stage of the experiment. These parameters were compared to each other in a pair-wise manner.

RESULTS

All wave latencies and IPL I-V were prolonged following induction of DM. Delay in waves III and V, and IPL I-V was significant (p<0.05). Pentoxifylline improved all of the wave latencies and IPL I-V, but significant improvement was observed in waves III and V (p<0.05). There was no significant difference between baseline measurements and measurements following pentoxifylline treatment.

Cognitive impairment correlates to low auditory event-related potential amplitudes in type 1 diabetes

Type 1 diabetes may be associated with a mild decline in cognitive function and mostly in mental speed. In order to study the pathophysiology of this, we have investigated auditory event-related potentials (AERP) and their relation to cognitive function in diabetes patients. AERP was recorded in patients with type 1 diabetes (n=119) and in a healthy control group (n=61). AERP was obtained with an odd-ball and a two-stimulus paradigm. Cognitive function was evaluated in 10 domains in the patients. Patients had normal N100 latency, but a highly significant decrease in auditory N100 amplitude (p<10(-6)), which correlated with a decrease in psychomotor speed but not with function in other domains. Psychomotor speed also correlated with P300 amplitude, although P300 amplitude was only slightly decreased in the patients. Even stronger correlations were found with the parietal N100-P300 peak-to-peak amplitude, which correlated both to psychomotor speed (rho=0.61, p<10(-7)) and processing speed (p<0.005). P300 latency was increased in patients, and this correlated to low global cognitive score and older age. We conclude that the decline in psychomotor speed in type 1 diabetes is associated with a highly significant decrease in the auditory N100 peak amplitude. This association and the relatively small abnormality in P300 latency is quite different from those generally found in dementia, and suggest that the underlying defect is located in the brain stem or the white matter. Presumably small conduction defects in ascending fibers can distort the firing synchrony necessary for signal generation in the cortex.

Sudden hearing loss as a first complication of long-standing Type 1 diabetes mellitus: a case report

The term 'sudden hypoacusis' describes a hearing loss of a rapid onset and unknown origin that can progress to severe deafness. Its pathophysiology is still unknown, the proposed aetiological mechanisms being vascular disease or autoimmune reaction. We present the case of a 19-year-old woman with Type 1 diabetes mellitus who experienced sudden hearing loss on her right side. She had no complications related to diabetes. After being referred to the hospital she was diagnosed with sudden sensorineural right-sided hearing loss accompanied by high frequency tinnitus. After administration of vasoactive drugs, there was partial improvement after 7 days, followed by gradual improvement over the next 4 weeks to 5 months. The tinnitus did not disappear completely. We conclude that hearing organ disturbances can be present in Type 1 diabetes and represent an early complication.