Hearing acuity in nonagenarians aged 90 and 95 assessed in a home setting using standardized pure-tone audiometry.

OBJECTIVE: Knowledge regarding hearing acuity in the nonagenarian age group is sparse. In this study we aimed to advance our understanding of hearing loss in the 10th decade of life. DESIGN: A cross-sectional study in which standardised hearing measurements were performed during home visits, which included care home facilities and nursing homes to maximise participation. STUDY SAMPLE: Two unselected groups of individuals aged 90 (n = 42) and 95 (n = 49), sampled from the population-based Gothenburg H70 Birth Cohort Studies. RESULTS: 98% of the participants (95% CI [95, 100]) had some degree of hearing loss in their better ear, with 83% (95% CI [73, 89]) having a potentially disabling hearing loss of moderate degree or worse, according to WHO criteria. Furthermore, differences between the two age groups (five years apart) indicate an increasing hearing loss, primarily at frequencies ≥ 2 kHz. CONCLUSION: Hearing loss was present in almost all of the participants in the nonagenarian age group and among a majority of them potentially to a degree that would warrant rehabilitation. Carrying out standardised hearing measurements in a home setting was feasible in this age group and enhanced the representativeness of the study population.

Bilateral hearing loss affected almost all of the individuals in the nonagenarian age group with 8 in 10 having hearing loss of a degree severe enough to warrant intervention or hearing aid prescription.The findings provide valuable insight into hearing acuity among nonagenarians. Many earlier studies were limited to subjective hearing assessments, reviews of medical records and/or screening tests performed by non-audiologists.The final sample size was smaller than initially planned due to the COVID-19 pandemic. However, measures were taken to optimise the representativeness of the study sample.

Accuracy of automated pure-tone audiometry in population-based samples of older adults.

OBJECTIVE: Automated pure-tone audiometry is frequently used in teleaudiology and hearing screening. Given the high prevalence of age-related hearing loss, older adults are an important target population. This study aimed to investigate the accuracy of automated audiometry in older adults, and to examine the influence of test frequency, age, sex, hearing and cognitive status. DESIGN AND STUDY SAMPLE: In a population-based study, two age-homogeneous samples of 70-year-olds (n = 238) and 85-year-olds (n = 114) were tested with automated audiometry in an office using circum-aural headphones and, around 4 weeks later, with manual audiometry conducted to clinical standards. The differences were analysed for individual frequencies (range: 0.25-8 kHz) and pure-tone averages. RESULTS: The mean difference varied across test frequencies and age groups, the overall figure being -0.7 dB (SD = 8.8, p < 0.001), and 68% to 94% of automated thresholds corresponded within ±10 dB of manual thresholds. The poorest accuracy was found at 8 kHz. Age, sex, hearing and cognitive status were not associated with the accuracy (ordinal regression analysis). CONCLUSIONS: Automated audiometry seems to produce accurate assessments of hearing sensitivity in the majority of older adults, but with larger error margins than in younger populations, and is not affected by relevant patient factors associated with old age.

Pathophysiological and Clinical Aspects of Hearing Loss Among 85-Year-Olds.

PURPOSE: This study aimed to identify the prevalence of conductive/mixed and sensorineural hearing loss, with an attempt to differentiate between sensory and neural components in 85-year-olds. METHOD: A comprehensive auditory test protocol, including pure-tone audiometry, speech audiometry, auditory brainstem response (ABR), and distortion product otoacoustic emission (DPOAE), was used to identify different types of hearing loss in 85-year-olds. This study comprised a subsample (n = 125) selected from an unscreened cohort of 85-year-olds born in 1930, within the Gothenburg H70 Birth Cohort Studies in Sweden. RESULTS: Test results were reported descriptively. Sensorineural hearing loss was present in one or both ears in almost all participants (98%), and the majority had absent DPOAEs. Only approximately 6% had additional conductive hearing loss, that is, mixed hearing loss. Approximately 20% of the participants with a pure-tone average at 0.5-4 kHz < 60 dB HL had worse word recognition scores compared with predicted scores by the Speech Intelligibility Index (SII), whereas only two participants were classified with neural dysfunction with the use of ABR. CONCLUSIONS: Sensorineural hearing loss, likely related to outer hair cell loss, was present in the vast majority of 85-year-olds. Conductive/mixed hearing loss appears to be relatively rare in advanced age. Poor word recognition scores in relation to SII-predicted scores were relatively common (20%) in 85-year-olds, whereas auditory neuropathy was only rarely identified (1.6%) by the use of ABR latencies. To explain abnormal word recognition and to identify the neural component of hearing loss among the older-old population, future research should consider factors such as listening effort and cognition among the older-old population.

Hearing Loss and Cognitive Function in Early Old Age: Comparing Subjective and Objective Hearing Measures.

INTRODUCTION: Population-based research has consistently shown that people with hearing loss are at greater risk of cognitive impairment. We aimed to explore the cross-sectional association of both subjective and objective hearing measures with global and domain-specific cognitive function. We also examined the influence of hearing aid use on the relationship. METHODS: A population-based sample (n = 1,105, 52% women) of 70-year-olds that were representative of the inhabitants of the city of Gothenburg, Sweden completed a detailed cognitive examination, pure-tone audiometry, and a questionnaire regarding perceived hearing problems. A subsample (n = 247, 52% women) also completed a test of speech-recognition-in-noise (SPRIN). Multiple linear regression analyses were conducted to explore the association of hearing with cognitive function, adjusting for sex, education, cardiovascular factors, and tinnitus. RESULTS: Global cognitive function was independently associated with the better ear pure-tone average across 0.5-4 kHz (PTA4, ß = -0.13, 95% CI, -0.18, -0.07), the better ear SPRIN score (ß = 0.30, 95% CI, 0.19, 0.40), but not with the self-reported hearing measure (ß = -0.02, 95% CI, -0.07, 0.03). Both verbally loaded and nonverbally loaded tasks, testing a variety of cognitive domains, contributed to the association. Hearing aid users had better global cognitive function than nonusers with equivalent hearing ability. The difference was only significant in the mild hearing loss category. DISCUSSION: In a population-based sample of 70-year-old persons without dementia, poorer hearing was associated with poorer global and domain-specific cognitive function, but only when hearing function was measured objectively and not when self-reported. The speech-in-noise measure showed the strongest association. This highlights the importance of including standardized hearing tests and controlling for hearing status in epidemiological geriatric research. More research is needed on the role that hearing aid use plays in relation to age-related cognitive declines.

Prevalence of hearing loss and need for aural rehabilitation in 85-year-olds: a birth cohort comparison, almost three decades apart.

OBJECTIVE: Many individuals >80 years have difficulties with speech communication due to age-related hearing loss and would benefit from aural rehabilitation. As the proportion of older people increases, there is a need to investigate the prevalence of "disabling hearing loss" to calculate future rehabilitation need. The aims are to determine the prevalence of hearing loss in an unscreened birth cohort of 85-year olds, and to identify differences in audiometric results between two birth cohorts, born 28-29 years apart. DESIGN: This is a population-based, cross-sectional study that is part of the Gothenburg H70 Birth Cohort Studies. STUDY SAMPLE: Hearing thresholds were measured and compared between 85-year olds born in 1930 (n = 286) and 1901-1902 (n = 249). RESULTS: Based on the WHO criteria, the prevalence of "disabling hearing loss" was 45% for men and 43% for women in the latest birth cohort. Hearing thresholds (0.5-4 kHz) for men improved compared with the earlier birth cohort. No such difference was observed for women. CONCLUSION: The prevalence of age-related hearing loss over three decades has decreased among 85-year-old men, but has been retained in women. The improvement for men occurred predominantly in the low-mid frequencies. An increased need for aural rehabilitation is expected due to demographic changes.

Prevalence of childhood hearing impairment in the County of Stockholm - a 40-year perspective from Sweden and other high-income countries.

OBJECTIVE: The purpose of this study was to determine the current prevalence of childhood hearing impairment (HI) in Sweden and to compare our data with previous studies from Sweden and other high-income countries. DESIGN: This was a cross-sectional study based on a register of children diagnosed with HI. Our results were compared with prevalence data from 18 studies from Sweden and other high-income countries, covering data collected from 1964 to the present. STUDY SAMPLE: In December 2017, a total of 1911 out of 524,957 children 0-18 years of age and living in Stockholm County were enrolled in the regional programme for HI intervention. RESULTS: The overall prevalence of unilateral and bilateral HI >20 dB was 3.6/1000. The overall prevalence of bilateral HI >40 dB HL was 1.5/1000, split into age groups the prevalence was 0.4/1000 (<1 year of age), 1/1000 (1-4 years), 1.5/1000 (5-9 years), 1.6/1000 (10-14 years), and 2.14/1000 (15-18 years). From 1 to 18 years of age, the prevalence increased by a factor of 3.5 for moderate to profound HI >40 dB HL (0.7 to 2.4/1000). CONCLUSION: The prevalence of HI across childhood in Stockholm County today is not significantly different from previous reports from Sweden and other high-income countries.

Prognostic Value of a Test of Central Auditory Function in Conversion from Mild Cognitive Impairment to Dementia.

BACKGROUND/OBJECTIVE: It has been suggested that central auditory processing dysfunction might precede the development of cognitive decline and Alzheimer's disease (AD). The Dichotic Digits Test (DDT) has been proposed as a test of central auditory function. Our objective was to evaluate the predictive capacity of the DDT in conversion from mild cognitive impairment (MCI) to dementia. METHODS: A total of 57 participants (26 females) with MCI were tested at baseline with pure tone audiometry, speech in quiet and in noise, and the DDT. The cognitive outcome was retrieved from medical files after 5 years. Groupwise comparisons of the baseline DDT scores were performed and the relative risk was calculated. RESULTS: Altogether 22 subjects developed any kind of dementia. Of the original 57 individuals within the MCI group, 15 developed AD and 7 developed other types of dementia. There was no significant difference in baseline DDT scores between the participants who converted to AD and those who did not. However, the group who developed other types of dementia (especially frontotemporal dementia) had lower DDT scores in the left ear than those participants who did not develop dementia. With a baseline DDT score below 50% correct responses, the participants diagnosed with MCI had a 2.49-times-higher risk of developing dementia than those with scores of 50% or better. CONCLUSION: The DDT as a central auditory test may be suitable when evaluating cognitive decline.

Auditory function and prevalence of specific ear and hearing related pathologies in the general population at age 70.

Objective: To describe the auditory function in early old age in detail based on both psychoacoustic and physiological measures, and to investigate the prevalence of specific audiological and otological pathologies.Design: An unscreened subsample from a population-based geriatric investigation was examined with otoscopy; tympanometry; pure-tone audiometry; word-recognition-in-noise test; distortion-product otoacoustic emissions; and auditory-evoked brainstem responses. Audiometric subtypes and diagnoses were established based on set criteria. The association between word scores and ABR was examined with linear regression analysis.Study Sample: 251 persons aged 70 (113 men, 138 women, born in 1944) that were representative of the inhabitants of the city of Gothenburg.Results: The prevalence of conductive pathology was 2% versus 49% for cochlear and 2% for auditory-neural pathology. Four percent had indeterminate type. Cochlear dysfunction was present in the majority of ears and around 20% performed worse-than-expected on speech testing. Poor performance on the speech in noise test was associated with prolonged interpeak latency interval of ABR waves I-V.Conclusion: Specific otological and audiological pathologies, other than cochlear hearing loss, are rare in the general population at age 70. Additionally, there is subtle evidence of age-related decline of the auditory nerve. Longitudinal follow-up would be of great interest.

Cross-sectional assessment of hearing acuity of an unscreened 85-year-old cohort - Including a 10-year longitudinal study of a sub-sample.

As the proportion of older people increases, it is important to investigate hearing acuity in older individuals and to calculate hearing decline for older ages, using standardised test protocols. The main aim of this study was to determine pure-tone hearing thresholds in an unscreened birth cohort of 85-year-olds born in 1930, living in an industrial Swedish city. A further aim was to describe hearing decline in men and women from 75 to 85 years of age with the aid of longitudinal data. The study was part of the Gothenburg H70 Birth Cohort Studies in Sweden. Hearing thresholds (0.25-8 kHz) were measured using automated pure-tone audiometry for 286 85-year-old participants. A subsample (n = 182) was hearing examined at 75 years of age and studied longitudinally from 75 to 85 years. At age 85 years, men had better hearing at low frequencies but poorer hearing at high frequencies than women. The longitudinal study showed a considerable decline between 75 and 85 years at mid-high frequencies (>1 kHz) and the amount of decline was similar between sexes. The results contribute to the estimation of the future need for hearing health services.

Noise Exposure and Hearing Impairment in Air Force Pilots.

OBJECTIVE: The goal of this study was to estimate noise exposure and hearing impairments in Swedish military pilots. It also aimed to analyze possible relations between noise exposure and hearing impairments.METHODS: The study group was an open cohort of 337 male pilots. They were longitudinally followed with pure tone audiograms every fifth year from the beginning of flight service until discharge. Outcome measures were prevalence of thresholds >20 dB HL and >40 dB HL at different ages, and incidence of impairments >20 dB HL, 30 dB HL, and 40 dB HL. Exposure variables were individual flight data and noise dose measurements. The ISO 1999 Database A was used for reference data.RESULTS: At 50 yr of age, 41% of the pilots were exposed to an equivalent noise dose exceeding the EU action level of Leq 80 dB(A). We observed significant elevated prevalence values of thresholds >20 dB HL in all age classes compared to the ISO 1999 Database A. These elevations were most pronounced at ages 30 and 40 yr and at 4 and 6 kHz in the left ear. Significantly elevated prevalence values of thresholds >40 dB HL compared to the ISO 1999 Database A were observed at age 40 and 50 yr at 4 and 6 kHz. In a Cox analysis we observed elevated hazard ratios of deteriorating thresholds with longer flight time/year in fast jet pilots.DISCUSSION: Military pilots had elevated prevalence values of hearing impairment. Of the subjects, 41% had been exposed to noise exceeding the EU risk limit. Increased flight time/year and flying fast jets were associated with elevated risk of hearing deterioration.Muhr P, Johnson A-C, Selander J, Svensson E, Rosenhall U. Noise exposure and hearing impairment in air force pilots. Aerosp Med Hum Perform. 2019; 90(9):757-763.

Treatment of military acoustic accidents with N-Acetyl-L-cysteine (NAC).

OBJECTIVE: To study if the antioxidant (AO) N-Acetyl-L-cysteine (NAC) reduces the risk of hearing loss after acoustic accidents in humans. DESIGN: A retrospective, observational study. STUDY SAMPLE: Personnel of the Swedish Armed Forces (SAF) exposed to military acoustic accidents during a 5 year period. Included in the study were 221 cases (mean age: 22.9 years). Most of the exposures, 84%, were weapon related. NAC (400 mg) was given directly after the accident in 146 cases; 75 had not received NAC. RESULTS: The prevalence of hearing thresholds ≥25 dB HL, and the incidence of threshold shifts ≥10 dB, was lower in the NAC group than in the non-NAC group directly after the noise exposure. The deterioration was temporary and not discernable a long time after the accident. The difference was most pronounced in the right ear. The risk reduction to get a temporary hearing loss (TTS), affecting one or both ears was 39% (significant) in the NAC group. CONCLUSIONS: The study has demonstrated a significant reduction of the incidence of TTS by the use of NAC. Since cases of both permanent hearing loss (PTS) and noise-induced tinnitus are recruited from cases with TTS, the demonstrated risk reduction indicates a positive effect of NAC.

Sensitivity and Specificity of Automated Audiometry in Subjects with Normal Hearing or Hearing Impairment.

OBJECTIVE: To investigate the sensitivity and specificity in an automatic computer-controlled audiometric set-up, used for screening purposes. DESIGN: Comparison between standardized audiometry and automated audiometry performed in the same participants. STUDY SAMPLE: In total, 100 participants (51 females and 49 males) were recruited to take part of this study the same day they visited the hearing clinic for clinical audiometry. Ages varied between 18 and 84 years (mean 45.9 in females, 52.3 in males). RESULTS: The participants were divided into groups, dependent of type of hearing. A total of 23 had normal hearing, 40 had sensorineural hearing loss, 19 had conductive hearing loss and 18 showed asymmetric hearing loss. The sensitivity for the automated audiometry was 86%-100% and the specificity 56%-100%. The group with conductive hearing loss showed the poorest sensitivity (86 %) and specificity (56 %). The group with sensorineural hearing loss showed the smallest variation in difference between the two methods. CONCLUSIONS: The results show that automated audiometry is a method suitable to screen for hearing loss. Screening levels need to be selected with respect to cause of screening and environmental factors. For patients with asymmetric hearing thresholds it is necessary to consider the effect of transcranial routing of signals.

Full-time exposure to occupational noise during pregnancy was associated with reduced birth weight in a nationwide cohort study of Swedish women.

Noise is a common exposure in the occupational work environment. Earlier studies of occupational noise and pregnancy outcome are few and show mixed results. To investigate if objectively assessed exposure to occupational noise during pregnancy is associated with reduced intrauterine growth and/or preterm birth a nationwide cohort study of 857,010 single births was initiated. Individual information on occupation and risk factors was retrieved from prenatal care interviews at pregnancy week 10. Occupational noise was classified into three exposure categories <75, 75-85, >85 dBA by a job exposure matrix. Odds ratios were adjusted for BMI, smoking, parity, education, physically strenuous work and low job control. Exposure to high (>85 dBA) levels of occupational noise throughout the pregnancy (full time workers) was associated with an increased risk of the child being born small for gestational age, OR 1.44 (95% CI 1.01 to 2.03) compared to noise exposure <75 dBA. A similar increase was seen for low birth weight OR 1.36 (95% CI 1.03 to 1.80) for high levels of noise. No clear association was seen for preterm birth. No consistent effects on birth outcome was observed in women who had worked part-time or were on leave of absence >21 days (median). In summary, full-time exposure to high levels of noise during pregnancy was associated with a slightly reduced fetal growth but not with preterm birth. The effect of intermediate occupational noise exposure (75-85 dBA) showed a small, but statistically increased risk for all studied birth outcomes. The study strengthens the evidence that pregnant women should not be long-term exposed to high levels >85 dBA of occupational noise during pregnancy. Intermediate exposure should be studied further.

A Longitudinal Study of Peripheral and Central Auditory Function in Alzheimer's Disease and in Mild Cognitive Impairment.

BACKGROUND/AIM: Central auditory processing disorder (CAPD) might precede the onset of Alzheimer's disease (AD). A method of evaluating CAPD is the dichotic digits test (DDT). The aim was to address this in a longitudinal setting. METHODS: A total of 136 individuals were assessed with peripheral and central hearing tests at baseline and at 5-year follow-up. RESULTS: Subjects with AD showed a significant decline in DDT scores of the right ear from baseline to follow-up. The other groups retained high DDT scores. Peripheral auditory function declined as expected according to age. CONCLUSIONS: Our study indicates that DDT performance reflects an ongoing process resulting in dementia.

Improved hearing in Swedish 70-year olds-a cohort comparison over more than four decades (1971-2014).

Objective: the world population is ageing rapidly. In light of these demographic changes, it is of interest to generate current data regarding the prevalence and characteristics of age-related hearing loss. The purpose of this study was to investigate hearing acuity and the prevalence of hearing loss in a contemporary age-homogenous cohort of old adults, and to assess secular trends in hearing function during the last half-century (1971-2014). Methods: we performed a prospective population-based cohort comparison study of unscreened populations. As part of a geriatric population-based study (H70), a new cohort of 70-year olds (n = 1,135) born in 1944 was tested with computerised automated pure-tone audiometry. The hearing thresholds were compared to three earlier born cohorts of 70-year olds, born in 1901-02 (n = 376), 1906-07 (n = 297) and 1922 (n = 226), respectively. Results: significant improvements in median pure-tone thresholds were seen at several frequencies in both men (range: 5-20 dB, P < 0.01) and women (range: 5-10 dB, P < 0.01). When investigating the effect of birth cohort on hearing in a linear regression, significant trends were found. Men's hearing improved more than women's. The prevalence of hearing loss declined in the study period (1971-2014) from 53 to 28% for men and 37 to 23% for women (P < 0.01). Conclusions: these results indicate that the hearing acuity in Swedish 70-year olds has improved significantly over more than four decades. The largest improvements were seen at 4-6 kHz in men, possibly reflecting a decrease in occupational noise exposure. Further studies are required to pinpoint the reasons for improved hearing-health among older people.

Declining and fluctuating prevalence values of hearing impairment in 18-year old Swedish men during three decades.

OBJECTIVE: To analyze time trends in prevalence of hearing impairment in almost complete birth cohorts of 18-year old Swedish men from 1970s up to 2010. STUDY GROUPS: Before 1999, all 18-year old men, in Sweden, were called for a compulsory conscription examination. In 1971-1999, the participation rate in audiometry was 73-95%. After 1999, when exemption from conscription was allowed, the participation rate gradually declined to 52% in 2004. Samples with participation rates below 50% (2005-2010) were considered non-representative and excluded from the analyses. RESULTS: High-frequency hearing impairments (HFHI) 35-40 dB HL and ≥45 dB HL showed a decreasing trend over the observed period, from a prevalence of 2.9% (35-40 dB HL) and 3.8% (≥45 dB HL) respectively in 1971 to 1.4% and 1.1% respectively in 2004. HFHI 25-30 dB HL, showed slow variations over time and decreased from 8.5% in 1971 to 3.2% in 1981 followed by an increase to 10.4% in 1992. After that year there was a decrease to 5.2% in 2004. The slow fluctuations affected only HFHI 25-30 dB HL, mainly at 6 kHz. The left ear was more affected than the right ear. CONCLUSIONS: The most important observation was a decrease of HFHI 35-40 dB HL by 52% percent and of HFHI ≥45 dB HL by 71% between the years 1971 and 2004. The prevalence of HFHI 25-30 dB HL in young Swedish males fluctuated over a period of 33 years. Possible reasons for these trends and variations are discussed.

Cigarette- and snus-modified association between unprotected exposure to noise from hunting rifle caliber weapons and high frequency hearing loss. A cross-sectional study among swedish hunters.

AIM: To investigate in this cross-sectional study among Swedish hunters if tobacco use modifies the previously observed association, expressed as prevalence ratio (PR), between unprotected exposure to impulse noise from hunting rifle caliber (HRC) weapons and high-frequency hearing impairment (HFHI). SETTINGS AND DESIGN: A nationwide cross-sectional epidemiologic study was conducted among Swedish sport hunters in 2012. MATERIALS AND METHODS: The study was Internet-based and consisted of a questionnaire and an Internet-based audiometry test. RESULTS: In all, 202 hunters completed a questionnaire regarding the hearing test. Associations were modeled using Poisson regression. Current, daily use of tobacco was reported by 61 hunters (19 used cigarettes, 47 moist snuff, and 5 both). Tobacco users tended to be younger, fire more shots with HRC weapons, and report more hunting days. Their adjusted PR (1-6 unprotected HRC shots versus 0) was 3.2 (1.4-6.7), P < 0.01. Among the nonusers of tobacco, the corresponding PR was 1.3 (0.9-1.8), P = 0.18. P value for the interaction was 0.01. The importance of ear protection could not be quantified among hunters with HRC weapons because our data suggested that the HFHI outcome had led to changes in the use of such protection. Among hunters using weapons with less sound energy, however, no or sporadic use of hearing protection was linked to a 60% higher prevalence of HFHI, relative to habitual use. CONCLUSION: Tobacco use modifies the association between exposure to unprotected impulse noise from HRC weapons and the probability of having HFHI among susceptible hunters. The mechanisms remain to be clarified, but because the effect modification was apparent also among the users of smokeless tobacco, combustion products may not be critical for this effect.

Mismatch Negativity and Ear Laterality in Alzheimer's Disease and in Mild Cognitive Impairment.

BACKGROUND: Cortical auditory event-related potentials (ERPs) were studied in order to measure mismatch negativity (MMN). Three groups of subjects were studied: patients with Alzheimer's disease (AD, n = 32), mild cognitive impairment (MCI, n = 44), and subjective memory complaints without cognitive decline (SMC, n = 27). A bottom up strategy was applied, and the right and left ears were stimulated monaurally. OBJECTIVE: To investigate MMN in AD and MCI, and in a clinical reference group. METHODS: ERPs were carried out with 500 tone pulses at 80 dBnHL. Each sequence included 80% standard tones (500 Hz) (f), and 20% deviant tones (1000 Hz) (r). MMN measurements were carried out by comparing the amplitudes of (f) and (r) recordings and to calculate the amplitude difference in µV for each group. The right and the left ears were analyzed separately. RESULTS: A left ear advantage (LEA) of MMN amplitude was demonstrated in the two groups with better cognition (the MCI and the SMC groups), but not in the AD group. DISCUSSION: The absence of MMN asymmetry in the AD group is possibly caused by a dysfunction to apprehend changes of tonal stimuli.

Clinical Study on 136 Children with Sudden Sensorineural Hearing Loss.

BACKGROUND: The prevalence of sudden sensorineural hearing loss in children (CSSNHL) is consistently increasing. However, the pathology and prognosis of CSSNHL are still poorly understood. This retrospective study evaluated clinical characteristics and possible associated factors of CSSNHL. METHODS: One hundred and thirty-six CSSNHL patients treated in Department of Otolaryngology-Head and Neck Surgery and Institute of Otolaryngology at Chinese PLA General Hospital between July 2008 and August 2015 were included in this study. These patients were analyzed for clinical characteristics, audiological characteristics, laboratory examinations, and prognostic factors. RESULTS: Among the 136 patients (151 ears), 121 patients (121 ears, 80.1%) were diagnosed with unilaterally CSSNHL, and 15 patients (30 ears, 19.9%) with bilateral CSSNHL. The complete recovery rate of CSSNHL was 9.3%, and the overall recovery rate was 37.7%. We found that initial degree of hearing loss, onset of treatment, tinnitus, the ascending type audiogram, gender, side of hearing loss, the recorded auditory brainstem response (ABR), and distortion product otoacoustic emissions (DPOAEs) had prognostic significance. Age, ear fullness, and vertigo had no significant correlation with recovery. Furthermore, the relevant blood tests showed 30.8% of the children had abnormal white blood cell (WBC) counts, 22.1% had elevated homocysteine levels, 65.8% had high alkaline phosphatase (ALP), 33.8% had high IgE antibody levels, and 86.1% had positive cytomegalovirus (CMV) IgG antibodies. CONCLUSIONS: CSSNHL commonly occurs unilaterally and results in severe hearing loss. Initial severe hearing loss and bilateral hearing loss are negative prognostic factors for hearing recovery, while positive prognostic factors include tinnitus, gender, the ascending type audiogram, early treatment, identifiable ABR waves, and DPOAEs. Age, vertigo, and ear fullness are not correlated with the recovery. Some serologic indicators, including the level of WBC, platelet, homocysteine, ALP, positive CMV IgG antibody, fibrinogen, and some immunologic indicators, are closely related to CSSNHL.