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.

Hearing Thresholds in Young Children With Otitis Media With Effusion With and Without Cleft Palate.

OBJECTIVE: To investigate hearing thresholds in children born with cleft palate and in children with otitis media with effusion but no cleft palate. DESIGN: Prospective longitudinal group comparison study. SETTING: University hospital. PARTICIPANTS: Sixteen children born with nonsyndromic cleft palate with or without cleft lip (CP±L) and 15 age-matched children with otitis media with effusion (OME) but without cleft. MAIN OUTCOME MEASURES: Hearing was tested at repeated occasions beginning with neonatal auditory brainstem response (ABR) at 1-4 months of age, and age-appropriate hearing tests from 9 to 36 months of age. RESULTS: The median ABR thresholds in both groups were elevated but did not differ significantly. At 12 months of age, the median 4 frequency averages at 500-1000-2000-4000 Hz (4FA) were indicative of mild hearing loss but significantly better in the CP±L-group than in the group without cleft (P < .01). There were no significant group-wise differences regarding the median 4FA at 24 and 36 months of age, and at 36 months, the median 4FA were normal in both groups. Both groups exhibited a significant improvement over time from the neonatal ABR thresholds to the 4FA at 36 months (CP±L-group P < .05; without CP±L-group P < .01). CONCLUSION: The hearing loss in children with CP±L was not more severe than among children with OME but without cleft palate; rather, at 12 months of age, the thresholds were significantly better in the CP±L-group than those in the group without cleft. The air conduction thresholds improved with age in both groups.

Clinical update on sensorineural hearing loss in Turner syndrome and the X-chromosome.

Hearing loss is one of the major medical concerns in girls and women with Turner syndrome (TS) and has a negative effect on well-being and quality of everyday life. Sensorineural hearing loss is the most common type of hearing loss, affecting more than half of adults with TS. Karyotypes with a loss of the short p-arm on the X-chromosome are more prone to ear and hearing problems. The importance of detecting, investigating, and treating hearing loss with hearing aids cannot be emphasized enough. The pathophysiology of the sensorineural hearing loss in TS is not known, but theories regarding estrogen deficiency, the cell cycle delay hypothesis, IGF-1 deficiency and the possible role of the KDM6A gene are discussed. Due to the diversity of symptoms and conditions within the same karyotype, a combination of genetic factors altered by epigenetic and/or hormonal effects is probable. Further research is needed regarding the pathophysiology of ear and hearing problems in TS to develop new treatment methods.

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.

Hearing thresholds and ventilation tube treatment in children with unilateral cleft lip and palate.

OBJECTIVE: Children with cleft lip and palate have a high prevalence of otitis media with effusion (OME) which is often associated with a fluctuating, conductive hearing loss in the low and mid-frequencies and a risk for permanent hearing loss in the higher frequencies. Although common, there is no consensus on the treatment of OME with ventilation tubes. The aim of this study is to document if the risk for permanent hearing loss and acquired cholesteatoma increases due to treatment with ventilation tubes (VT treatments) during childhood in a group of children with cleft lip and palate. METHODS: A retrospective medical chart review of 33 children (25 boys and 8 girls) born with unilateral cleft lip and palate (UCLP) was completed. Audiological data (results of hearing sensitivity tests, the total number of hearing tests, and number of VT treatments) were extracted from medical records from when the children were 4-7 and >7-10 years of age. RESULTS: The hearing thresholds in the speech frequencies improved with age (p < 0,05) but a minority of the children continued to present with elevated hearing thresholds in the higher frequencies at >7-10 years of age. There were no significant correlations between number of VT treatments and hearing thresholds at >7-10 years. Four of the 33 children presented with complications: two children exhibited perforations of the ear drum (6.1%) and two children developed unilateral cholesteatoma (6.1%). CONCLUSION: In the current study, the hearing sensitivity of children with cleft lip and palate improved with age. However, this improvement was not seen in the higher frequencies. Twelve percent of the children experienced complications following VT treatments. Due to these complications, it is recommended that all children with cleft palate should have routine follow-ups by an ENT doctor and audiologist. As part of the routine follow-up care, hearing assessments should be performed before and after VT treatments.

Audiometric features in young adults with Turner syndrome.

OBJECTIVE: Hearing loss (HL) is a known problem in adults with Turner syndrome (TS). The aim of this study was to investigate audiometric features in young adults with TS and the extent of hearing aid provision. DESIGN: Patients were recruited from the Turner centre at Karolinska University Hospital. Analysis of audiograms was made in relation to hearing aid use, a Swedish normal hearing cohort and the need for hearing rehabilitation. STUDY SAMPLE: Sixty-four women with TS aged 25-38 years at the time of their audiological testing. RESULTS: Fifty-two percent had impaired hearing in at least one ear. Sensorineural hearing loss (SNHL) was the most common type of HL, most often characterised by a high-frequency loss and/or a mid-frequency dip. Conductive HL was uncommon in young adults with TS, even though 47 percent were otitis prone as children. Eight of 64 women had previously been fitted with hearing aids. CONCLUSIONS: There is undoubtedly a need for hearing rehabilitation in young adults with TS. Questions about hearing must be asked by all doctors treating women with TS to identify those in need for hearing rehabilitation, even if they have an audiogram with a normal pure tone average.

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.

Age-related hearing decline in individuals with and without occupational noise exposure.

This study was conducted to compare the pattern of age-related hearing decline in individuals with and without self-reported previous occupational noise exposure. This was a prospective, population-based, longitudinal study of individuals aged 70-75 years, from an epidemiological investigation, comprising three age cohorts. In total there were 1013 subjects (432 men and 581 women). Participants were tested with pure tone audiometry, and they answered a questionnaire to provide information regarding number of years of occupational noise exposure. There were no significant differences in hearing decline, at any frequency, for those aged 70-75 years between the noise-exposed (N= 62 men, 22 women) and the nonexposed groups (N = 96 men, 158 women). This study supports the additive model of noise-induced hearing loss (NIHL) and age-related hearing loss (ARHL). The concept of different patterns of hearing decline between persons exposed and not exposed to noise could not be verified.

Hearing decline in menopausal women--a 10-year follow-up.

CONCLUSIONS: An unexpected rapid hearing decline remained after the 10-year follow up, similar to the hearing decline in 70-year-old women in reference materials. No clear changes concerning hearing in the peri- and postmenopausal period were noted. OBJECTIVE: To assess whether hearing decline correlates with menopause and/or cortisol blood levels. METHODS: A prospective individual longitudinal study of peri-menopausal women followed for 10 years was performed at baseline, and after 2, 7 and 10 years, respectively. With a starting age of around 51 years, 100 women remained in the study after 10 years. Pure-tone audiometry and cortisol blood testing were performed at all visits. RESULTS: A continuous hearing decline, at all frequencies, was found during the follow-up time. The rate of decline during the menopausal period was higher than compared with reference materials for the same age group. The correlation with time for menopause is most apparent at 1 and 3 kHz where the hearing decline is more rapid after menopause than before. Serum cortisol levels did not correlate with rate of hearing decline.

Dietary habits and hearing.

UNLABELLED: Abstract Objective: Study groups from three age cohorts of 70-75 year-olds were investigated to search for possible correlations between dietary habits and auditory function. DESIGN: A cross-sectional, epidemiological study. STUDY SAMPLE: A total number of 524 people (275 women, 249 men) were recruited from three age cohorts. The study sample was representative of the general population. All participants answered a diet history and were tested with pure-tone audiometry. Eleven categories of food consumption were related to pure-tone averages of low-mid frequency hearing, and high frequency hearing. RESULTS: Two consistent correlations between diet and hearing were observed. One was a correlation between good hearing and a high consumption of fish in the male group. The other was a correlation between poor high frequency hearing and a high consumption of food rich in low molecular carbohydrates in both genders; a larger effect size was seen in females. CONCLUSIONS: The study indicates that diet is important for aural health in aging. According to this study fish is beneficial to hearing, whereas consumption of "junk food", rich in low molecular carbohydrates, is detrimental. Other correlations, e.g. between high consumption of antioxidants, were not demonstrated here, but cannot be excluded.

Hearing of 75-year old persons over three decades: has hearing changed?

OBJECTIVE: The state of hearing in 75-year old persons was measured in a population based epidemiological study with the aim of studying if hearing had changed during a time span of 29 years. DESIGN: An epidemiological study of generational effects in three age cohorts. STUDY SAMPLE: Three age cohorts were included: cohort 1 (n: 267) born in 1976-77, cohort 4 (n: 197) in 1990-91, and cohort 6 (n: 570) in 2005. The same test procedures using pure-tone audiometry and a short questionnaire were applied to the three cohorts of 75-year old residents in the same city. RESULTS: The hearing was essentially unchanged during the span of the investigation-almost three decades. Low-frequency hearing was up to about 10 dB poorer in the most recently studied cohort compared to the previously studied cohorts. The reason for this difference is considered to depend on methodological factors. Self-assessed hearing and tinnitus was mainly unchanged, or had minor changes both to the better and to the worse. CONCLUSIONS: The hearing, both measured with pure-tone audiometry and with a short questionnaire, of 75-year old persons has not changed at all, or only marginally, over three decades.

Short-term longitudinal study of central auditory function in Alzheimer's disease and mild cognitive impairment.

BACKGROUND/AIMS: Central auditory function can be studied to monitor the progression of mild cognitive impairment to dementia. Our aim was to address this issue in a prospective longitudinal setting. METHODS: Tests of central hearing function were performed on 70 subjects with either Alzheimer's disease (AD) or mild cognitive impairment, and in controls with subjective memory complaints but normal cognition. The time span until follow-up was 1.5 years. RESULTS: The dichotic digit free recall test showed a significant decline in the AD group compared with the controls (left ear). CONCLUSION: The short time span was long enough to disclose a central auditory processing decline in AD.

Otological diagnoses and probable age-related auditory neuropathy in "younger" and "older" elderly persons.

OBJECTIVE: Audiological data from a population based epidemiological investigation were studied on elderly persons. Specific diagnoses of otological and audiological disorders, which can result in hearing loss, were searched for. DESIGN: A retrospective register study. STUDY SAMPLE: Three age cohorts, 474 70- and 75-year olds ("younger"), and 252 85-year olds ("older"), were studied. Clinical pure tone and speech audiometry was used. Data from medical files were included. RESULTS: Conductive hearing loss was diagnosed in 6.1% of the "younger" elderly persons, and in 10.3% of the "older" ones. Specific diagnoses (chronic otitis media and otosclerosis) were established in about half of the cases. Sensorineural hearing loss, other than age-related hearing loss and noise induced hearing loss, was diagnosed in 3.4 % and 5.2% respectively. Severely impaired speech recognition, possibly reflecting age-related auditory neuropathy, was found in 0.4% in the "younger" group, and in 10% in the "older" group. Bilateral functional deafness was present in 3.2% of the 85-year-old persons, but was not present in the 70-75-year group. CONCLUSION: The incidence of probable age-related auditory neuropathy increases considerably from 70-75 to 85 years. There are marked differences between "younger" and "older" elderly persons regarding hearing loss that severely affects oral communication.

Central auditory function in early Alzheimer's disease and in mild cognitive impairment.

OBJECTIVE: to investigate auditory function in subjects with early Alzheimer's disease, mild cognitive impairment and with subjective memory complaints, in search of signs of central auditory processing dysfunction even in early stages of cognitive impairment. DESIGN AND SUBJECTS: a consecutive group of men and women, referred to the Memory Clinic at the Karolinska University Hospital, was approached for inclusion in this prospective study. One hundred and thirty-six subjects, mean age 64 years (range 50-78 years), diagnosed with Alzheimer's disease (n = 43), mild cognitive impairment (n = 59) or with subjective memory complaints (n = 34), were included. METHODS: auditory function was assessed with pure tone audiometry, speech perception in quiet and in background noise and dichotic digits tests with two or three digits. RESULTS: pure tone audiometry and speech perception scores in quiet and in background noise were normal for age and without between-group differences. Dichotic digits tests showed strongly significant differences between the three groups, where the Alzheimer's disease group performed significantly poorer than the other two groups, with the mild cognitive impairment group in an intermediate position. CONCLUSIONS: our results demonstrate that central auditory processing dysfunction is highly evident in subjects with Alzheimer's disease, and to a considerable extent even in subjects with mild cognitive impairment.

A longitudinal study of hearing decline in women with Turner syndrome.

CONCLUSION: Young and middle-aged women with Turner syndrome (TS) have a progressive type of hearing impairment, deteriorating rapidly in adult age. The hearing decline seems to consist of two patterns: a mid-frequency dip, likely of a genetic origin, and a high-frequency loss resembling age-related hearing impairment -- possibly influenced by estrogen deficiency. OBJECTIVES: This was a longitudinal study of hearing thresholds in a group of women with TS that also aimed to determine whether the factors initial age, initial hearing level, karyotype, and presence/absence of a mid-frequency dip influence the rate of decline and could serve as prognostic markers. SUBJECTS AND METHODS: Audiograms of air conduction thresholds in 69 women with TS (aged 28-62 years) were performed twice with an average interval of 10 years. RESULTS: The rate of hearing decline is much higher in women with TS than in age-matched women from the general population. The decline rate is comparable to that seen in 70-90-year-old women, regardless of initial age, hearing level, karyotype, or presence of a mid-frequency dip. The rate of decline is especially high in the high-frequency region, 0.8-2.2 dB per year. The presence of a mid-frequency dip is an especially strong predictor for a future high rate of hearing decline with subsequent social consequences.

Estrogen and hearing from a clinical point of view; characteristics of auditory function in women with Turner syndrome.

Turner syndrome is a chromosomal aberration affecting 1:2000 newborn girls, in which all or part of one X chromosome is absent. This leads to ovarial dysgenesis and little or no endogenous estrogen production. These women have, among many other syndromal features, a high occurrence of ear and hearing problems, and neurocognitive dysfunctions, including reduced visual-spatial abilities; it is assumed that estrogen deficiency is at least partially responsible for these problems. In this, study 30 Turner women aged 40-67, with mild to moderate hearing loss, performed a battery of hearing tests aimed at localizing the lesion causing the sensorineural hearing impairment and assessing central auditory function, primarily sound localization. The results of TEOAE, ABR and speech recognition scores in noise were all indicative of cochlear dysfunction as the cause of the sensorineural impairment. Phase audiometry, a test for sound localization, showed mild disturbances in the Turner women compared to the reference group, suggesting that auditory-spatial dysfunction is another facet of the recognized neurocognitive phenotype in Turner women.

Hearing in women at menopause. Prevalence of hearing loss, audiometric configuration and relation to hormone replacement therapy.

CONCLUSION: Hormone replacement therapy (HRT) may have a protective effect on hearing impairment in postmenopausal women. New guidelines for classification of audiometric configuration in age-related hearing loss are suggested. OBJECTIVES: To describe prevalence of hearing loss and audiometric configuration in a group of middle-aged women with respect to menopausal stage and HRT. SUBJECTS AND METHODS: A total of 143 women around menopause were sampled through the Swedish population register. The mean hearing threshold levels were compared according to menopausal status. The audiograms in the 57 women with hearing loss were classified according to audiometric configuration. RESULTS: In all, 57 women (40%) had any kind of hearing loss; 42 had very minute hearing loss; 15 had a 4FA (average of thresholds at 0.5, 1, 2, and 4 kHz) of at least 20-39 dB HL in at least one ear. Two of these had a 4FA of 40-69 dB HL in at least one ear. The most common configurations were: gently sloping (47%), steeply sloping (14%), and high-frequency U-shaped (14%). The postmenopausal women who were not on HRT had poorer hearing mainly at 2 and 3 kHz, compared with pre- and perimenopausal women, and postmenopausal women on HRT.