The Cost-Effectiveness of Different Hearing Screening Strategies for 50- to 70-Year-Old Adults: A Markov Model.

OBJECTIVE: To assess the cost-effectiveness of screening 50- to 70-year-old adults for hearing loss in The Netherlands. We compared no screening, telephone screening, Internet screening, screening with a handheld screening device, and audiometric screening for various starting ages and a varying number of repeated screenings. METHODS: The costs per quality-adjusted life-year (QALY) for no screening and for 76 screening strategies were analyzed using a Markov model with cohort simulation for the year 2011. Screening was deemed to be cost-effective if the costs were less than €20,000/QALY. RESULTS: Screening with a handheld screening device and audiometric screening were generally more costly but less effective than telephone and Internet screening. Internet screening strategies were slightly better than telephone screening strategies. Internet screening at age 50 years, repeated at ages 55, 60, 65, and 70 years, was the most cost-effective strategy, costing €3699/QALY. At a threshold of €20,000/QALY, this strategy was with 100% certainty cost-effective compared with current practice and with 69% certainty the most cost-effective strategy among all strategies. CONCLUSIONS: This study suggests that Internet screening at age 50 years, repeated at ages 55, 60, 65, and 70 years, is the optimal strategy to screen for hearing loss and might be considered for nationwide implementation.

Specialised treatment based on cognitive behaviour therapy versus usual care for tinnitus: a randomised controlled trial.

BACKGROUND: Up to 21% of adults will develop tinnitus, which is one of the most distressing and debilitating audiological problems. The absence of medical cures and standardised practice can lead to costly and prolonged treatment. We aimed to assess effectiveness of a stepped-care approach, based on cognitive behaviour therapy, compared with usual care in patients with varying tinnitus severity. METHODS: In this randomised controlled trial, undertaken at the Adelante Department of Audiology and Communication (Hoensbroek, Netherlands), we enrolled previously untreated Dutch speakers (aged >18 years) who had a primary complaint of tinnitus but no health issues precluding participation. An independent research assistant randomly allocated patients by use of a computer-generated allocation sequence in a 1:1 ratio, stratified by tinnitus severity and hearing ability, in block sizes of four to receive specialised care of cognitive behaviour therapy with sound-focused tinnitus retraining therapy or usual care. Patients and assessors were masked to treatment assignment. Primary outcomes were health-related quality of life (assessed by the health utilities index score), tinnitus severity (tinnitus questionnaire score), and tinnitus impairment (tinnitus handicap inventory score), which were assessed before treatment and at 3 months, 8 months, and 12 months after randomisation. We used multilevel mixed regression analyses to assess outcomes in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00733044. FINDINGS: Between September, 2007 and January, 2011, we enrolled and treated 492 (66%) of 741 screened patients. Compared with 247 patients assigned to usual care, 245 patients assigned to specialised care improved in health-related quality of life during a period of 12 months (between-group difference 0·059, 95% CI 0·025 to 0·094; effect size of Cohen's d=0·24; p=0·0009), and had decreased tinnitus severity (-8·062, -10·829 to -5·295; d=0·43; p<0·0001) and tinnitus impairment (-7·506, -10·661 to -4·352; d=0·45; p<0·0001). Treatment seemed effective irrespective of initial tinnitus severity, and we noted no adverse events in this trial. INTERPRETATION: Specialised treatment of tinnitus based on cognitive behaviour therapy could be suitable for widespread implementation for patients with tinnitus of varying severity. FUNDING: Netherlands Organisation for Health Research and Development (ZonMW).

Functional impairment of the auditory pathway after perinatal asphyxia and the short-term effect of perinatal propofol anesthesia in lambs.

BACKGROUND: Sensorineural hearing loss (SNHL) is a common feature in the postasphyxial syndrome in newborns. Several anesthetic drugs have been proposed to attenuate secondary neuronal injury elicited by hypoxia-ischemia. We hypothesized that propofol anesthesia reduces auditory impairment after perinatal asphyxia in comparison with isoflurane. METHODS: Twenty-three pregnant ewes were randomized to propofol or isoflurane anesthesia and sedation. The lambs underwent in utero umbilical cord occlusion (isoflurane n = 5; propofol n = 7) and were compared with sham-treated animals (isoflurane n = 5; propofol n = 6) at a gestational age of 133 d. For 8 h after delivery by cesarean section, repeated auditory brainstem responses (ABRs) were recorded to obtain hearing thresholds, peak amplitudes, latencies, and interpeak latencies. RESULTS: Significantly elevated mean thresholds, diminished amplitudes, and elevated latencies were observed in the asphyxia group relative to the control group through the observation period. Comparison of anesthetic treatment in the asphyxia group revealed a significantly lower elevation in threshold and less impairment in the ABR amplitudes and latencies during propofol anesthesia as compared with isoflurane anesthesia. CONCLUSION: Our results support the hypothesis that anesthesia with propofol has a preventive effect on the functional changes to the auditory pathway in the event of perinatal asphyxia.

Tinnitus: a cost study.

OBJECTIVES: The aim of this study was to examine the costs of tinnitus in The Netherlands from a health care and a societal perspective. Furthermore, the impact of disease characteristics and demographic characteristics on these costs were examined. METHODS: A bottom-up cost of illness study was performed, using the baseline data on a cost questionnaire of a randomized controlled trial investigating the (cost) effectiveness of an integral multidisciplinary treatment for tinnitus versus care as usual. Mean yearly costs were multiplied by the prevalence figure of tinnitus for the adult general population to estimate the total cost of illness of tinnitus to society. Because cost data usually are not normally distributed, a nonparametric bootstrap resampling procedure with 1000 simulations was performed to determine statistical uncertainty of the cost estimates per category. Several questionnaires measuring disease and demographic characteristics were administered. The impact of disease characteristics and demographics on costs was investigated using a multivariate regression analysis. RESULTS: Total mean societal cost of illness was €6.8 billion (95% confidence interval: €3.9 billion-€10.8 billion). The larger part of total cost of illness was not related to health care. Total mean health care costs were €1.9 billion (95% confidence interval: €1.4 billion-€2.5 billion). Significant predictors of both health care costs and societal costs were tinnitus severity, age, shorter duration of tinnitus, and more severe depression. CONCLUSION: The economical burden of tinnitus to society is substantial, and severity of tinnitus is an important predictor of the costs made by patients.

Qualitative interviews on the beliefs and feelings of adults towards their ownership, but non-use of hearing aids.

OBJECTIVE: Up to a quarter of the adults who own hearing aids never use them. To provide these 'non-users' with the best help, hearing care professionals need to have an in-depth understanding of the non-users' beliefs and feelings with regard to the non-use. This qualitative study explored these beliefs and feelings in order to increase our understanding of hearing aid non-users. DESIGN: Individual face-to-face semi-structured interviews were completed. STUDY SAMPLE: Eleven hearing aid owners (aged 54-80 years) who reported that they never or hardly ever used their hearing aids. RESULTS: The participants expressed a variety of feelings towards their non-use, including indifference, self-annoyance, frustration, powerlessness, shame, and guilt. Their feelings were related to beliefs about: (1) the severity of their hearing handicap with and without hearing aids, (2) whom or what was responsible for the non-use, and (3) the attitudes of significant others towards the non-use. CONCLUSIONS: Hearing-aid non-users differ in their beliefs and feelings towards the non-use. A patient-centred approach is needed.

Screening for hearing loss versus parental concern regarding hearing problems: Subsequent referral and treatment for otitis media in the Netherlands.

OBJECTIVE: The present study investigates whether general practitioner (GP) consultation initiated by failing the population hearing screening at age nine months or GP consultation because of parental concern over ear/hearing problems was more important in deciding on referral and/or surgical treatment of otitis media (OM). DESIGN: A questionnaire covering the history between birth and 21 months of age was used to obtain information on referral after failing the hearing screening, GP consultations for ear/hearing problems, and subsequent referral to a specialist and possible surgical treatment at an ENT department. SETTING: The province of Limburg, the Netherlands. SUBJECTS: Healthy infants invited for the hearing screening at age nine months, who responded in an earlier study called PEPPER (Persistent Ear Problems, Providing Evidence for Referral, response rate 58%). MAIN OUTCOME MEASURES: The odds of a child being surgically treated for OM. RESULTS: The response rate for the present questionnaire was 72%. Of all children tested, 3.9% failed the hearing screening and were referred to their GP. Of all 2619 children in this study, 18.6% visited their GP with ear/hearing problems. Children failing the hearing screening without GP consultation for ear/hearing problems were significantly more often treated surgically for OM than children passing the hearing screening but with GP consultation for ear/hearing problems. CONCLUSION: Objectified hearing loss, i.e. failing the hearing screening, was important in the decision for surgical treatment in infants in the Netherlands.

Risk factors for failing the hearing screen due to otitis media in Dutch infants.

Hearing loss from otitis media (OM) can affect young children's development. Some children with persistent OM-related hearing loss and associated problems can benefit from treatment, but researchers and clinicians are still unclear on how to identify them best. The present study aims to determine which factors are most related to the hearing loss in OM, as a first step towards an effective case-finding instrument for detecting infants with persistent OM-related hearing loss. The full PEPPER ('Persistent Ear Problems, Providing Evidence for Referral') item pool includes a wide range of risk factors for OM in a single questionnaire, and is easily completed by parents or guardians. The questionnaire was sent to all children invited for the universal hearing screen at age 9 months in Limburg, The Netherlands. Repeatedly failing of the hearing screen was used as outcome marker indicative of OM-related chronic hearing loss. Univariate analyses were conducted to determine statistically significant risk factors predicting 'fail' cases at this hearing screen. Five items were found as individually predictive of hearing screen failure and subsequent referral: 'having severe cold symptoms', 'attending day care with >4 children', 'having siblings', 'severe nasal congestion' and 'male gender'. Suitably worded parental questions document risk factors for OM-related hearing loss in infants, broadly consistent with past general literature on OM risk factors, but more focused. The findings justify further optimising and evaluation of an additive or multiplicative combination of these questions as a means for selecting and routing an infant with diagnosed or suspected OM to further care.

Speech perception after early-life otitis media with fluctuating hearing loss.

The present study examined the effect of early-life otitis media and its associated fluctuating hearing loss on categorical speech perception in 7-year-old Dutch children. The middle ear status of these children had been followed prospectively in their first 2 years of life. Identification and discrimination of speech sounds differing in place of articulation were tested at school age and outcomes were significantly related to otitis media-related hearing loss. Results revealed that phoneme identification and discrimination were affected by early-life hearing loss. It is not otitis media per se, but rather the relative severity of hearing loss resulting from early-life otitis media which is related to poorer categorical speech perception abilities in school-age children.

Tinnitus interferes with daily life activities: a psychometric examination of the Tinnitus Disability Index.

OBJECTIVES: Tinnitus Disability Index (TDI) is presented as a novel and brief self-report measure for the assessment of the interference of tinnitus with performance in specific daily life activities. We hypothesized that the TDI is a reliable and valid measure and that tinnitus disability is strongly associated with tinnitus severity, subjective tinnitus intensity ratings, and ratings of general health. DESIGN: Six hundred fifteen tinnitus patients from across the Netherlands completed online a number of questionnaires about their tinnitus, their general health, and demographics. Two samples were extracted by a random split: Sample I (N = 311) for exploratory factor analysis and Sample II (N = 304) for confirmatory analysis, using structural equation modeling. One hundred forty-three of the first included respondents repeated assessment after a 2-wk time interval for test/retest analysis. Regression analyses were employed to investigate construct validity. RESULTS: Present analyses reveal that tinnitus disability, as measured with the TDI, might be best understood as a single-component construct, that is, one single underlying factor. The TDI is reliable over time, and tinnitus-related disability, as measured with the TDI, is strongly associated with subjective ratings of tinnitus intensity, negatively associated with quality of life ratings, and distress due to tinnitus. CONCLUSIONS: The TDI is a brief and easily administered index measuring a unique construct, namely the experienced interference of the tinnitus with daily life activities, which is invaluable in the assessment and treatment of tinnitus patients.

Assessment of health state in patients with tinnitus: a comparison of the EQ-5D and HUI mark III.

OBJECTIVES: Expressing the outcomes of treatment in quality-adjusted life years is increasingly important as a tool to aid decision makers concerning the allocation of scarce resources within the health care sector. A quality-adjusted life year is a measure of life expectancy that is weighted by health-related quality of life. These weights are referred to as utility scores and are usually measured by multiattribute utility measures. Several studies found that different utility measures provide different estimates of the same person's level of utility. The aim of this study was to investigate which of two widely used utility measures, the EQ-5D and the HUI mark III, is preferred in a tinnitus population. METHODS: Baseline and follow-up data on EQ-5D and HUI mark III of 429 patients of a randomized controlled clinical trial, investigating cost-effectiveness of usual care versus specialized care of tinnitus, were included. Agreement, discriminative power, and responsiveness of the health state description and the utility scores were examined. RESULTS: Corresponding dimensions of the EQ-5D and HUI mark III showed large correlations; although ceiling effects were more frequently observed in the EQ-5D. Mean utility scores for EQ-5D (0.77; SD 0.22) and HUI mark III (0.64; SD 0.28) were significantly different (Wilcoxon signed ranks test, p < 0.001), and agreement was low to moderate (intraclass correlation coefficient = 0.53). Both health state description and utility scores of both measures discriminated between different severity groups. These groups were based on baseline scores of the Tinnitus Questionnaire. The HUI mark III had a higher ability than the EQ-5D to detect improved patients from randomly selected pairs of improved and unimproved patients. CONCLUSION: This study shows that different utility measures lead to different health state descriptions and utility scores among tinnitus patients. However, both measures are capable of discriminating between clinically different groups. The HUI mark III is more responsive than the EQ-5D, and therefore preferred in a tinnitus population.

Frequency shifts with age in click-evoked otoacoustic emissions of preterm infants.

A previous study [Brienesse et al. (1997). Pediatr. Res. 42, 478-483] demonstrated a positive shift with increasing postmenstrual age (PMA) in the frequencies of synchronized spontaneous otoacoustic emissions (SSOAEs) in preterm infants. We used a mixed model approach to describe a shift with PMA in the spectra of click-evoked otoacoustic emissions (CEOAEs) measured in a group of 22 preterm infants. The rate in shift in CEOAE spectral components was found to be frequency dependent, with a mean estimate of 10 Hz/week for frequencies around 2 kHz and 30 Hz/week for frequencies around 4.25 kHz. This rate decreased with increasing PMA. Because SSOAEs are often part of the CEOAE response, a comparison was made between the shifts in SSOAEs and CEOAEs in a sub-group of 16 preterm infants. The results indicate that the shifts found for both types of OAE are similar, which supports a common mechanism for this change in OAE-characteristic. At present it is not clear to what extent developmental processes in the cochlea and the middle ear can account for these frequency shifts in the spectra of CEOAEs and SSOAEs during the preterm period.

Interventions following hearing screening in adults: a systematic descriptive review.

OBJECTIVE: Adult hearing screening may be a solution to the under-diagnosis and under-treatment of hearing loss in adults. Limited use and satisfaction with hearing aids indicate that consideration of alternative interventions following hearing screening may be needed. The primary aim of this study is to provide an overview of all intervention types that have been offered to adult (≥ 18 years) screen-failures. DESIGN: Systematic literature review. Articles were identified through systematic searches in PubMed, EMBASE, Cinahl, the Cochrane Library, private libraries, and through reference checking. RESULTS: Of the initial 3027 papers obtained from the searches, a total of 37 were found to be eligible. The great majority of the screening programmes (i.e. 26) referred screen-failures to a hearing specialist without further rehabilitation being specified. Most of the others (i.e. seven) led to the provision of hearing aids. Four studies offered alternative interventions comprising communication programme elements (e.g. speechreading, hearing tactics) or advice on environmental aids. CONCLUSIONS: Interventions following hearing screening generally comprised referral to a hearing specialist or hearing aid rehabilitation. Some programmes offered alternative rehabilitation options. These may be valuable as an addition to or replacement of hearing aid rehabilitation. It is recommended that this be addressed in future research.

A Multinational Cost-Consequence Analysis of a Bone Conduction Hearing Implant System-A Randomized Trial of a Conventional vs. a Less Invasive Treatment With New Abutment Technology.

Background: It is hypothesized that, for patients with hearing loss, surgically placing an implant/abutment combination whilst leaving the subcutaneous tissues intact will improve cosmetic and clinical results, increase quality of life (QoL) for the patient, and reduce medical costs. Here, incremental costs and consequences associated with soft tissue preservation surgery with a hydroxyapatite (HA)-coated abutment (test) were compared with the conventional approach, soft tissue reduction surgery with an all-titanium abutment (control). Methods: A cost-consequence analysis was performed based on data gathered over a period of 3 years in an open randomized (1:1) controlled trial (RCT) running in four European countries (The Netherlands, Spain, France, and Sweden). Subjects with conductive or mixed hearing loss or single-sided sensorineural deafness were included. Results: During the first year, in the Netherlands (NL), France (FR), and Spain (ES) a net cost saving was achieved in favor of the test intervention because of a lower cost associated with surgery time and adverse event treatments [NL €86 (CI -50.33; 219.20), FR €134 (CI -3.63; 261.30), ES €178 (CI 34.12; 97.48)]. In Sweden (SE), the HA-coated abutment was more expensive than the conventional abutment, which neutralized the cost savings and led to a negative cost (SE €-29 CI -160.27; 97.48) of the new treatment modality. After 3 years, the mean cost saving reduced to €17 (CI -191.80; 213.30) in the Netherlands, in Spain to €84.50 (CI -117.90; 289.50), and in France to €80 (CI -99.40; 248.50). The mean additional cost in Sweden increased to €-116 (CI -326.90; 68.10). The consequences in terms of the subjective audiological benefit and Health-related quality of life (HRQoL) were comparable between treatments. A trend was identified for favorable results in the test group for some consequences and statistical significance is achieved for the cosmetic outcome as assessed by the clinician. Conclusions: From this multinational cost-consequence analysis it can be discerned that health care systems can achieve a cost saving during the first year that regresses after 3 years, by implementing soft tissue preservation surgery with a HA-coated abutment in comparison to the conventional treatment. The cosmetic results are better. (sponsored by Cochlear Bone Anchored Solutions AB; Clinical and health economic evaluation with a new Baha® abutment design combined with a minimally invasive surgical technique, ClinicalTrials.gov NCT01796236).

Willingness to accept versus willingness to pay in a discrete choice experiment.

OBJECTIVES: Our main objective was to compare willingness to accept (WTA) and willingness to pay (WTP) in a discrete choice experiment on hearing aid provision. Additionally, income effect and endowment effect were explored as possible explanations for the disparity between WTA and WTP, and the impact of using a WTA and/or WTP format to elicit monetary valuations on the net benefit of the new organization of hearing aid provision was examined. METHODS: Choice sets were based on five attributes: performer of the initial assessment; accuracy of the initial assessment; duration of the pathway; follow-up at the ear, nose, and throat specialist; and costs. Persons with hearing complaints randomly received a WTP (costs defined as extra payment) or WTA (costs defined as discount) version of the experiment. In the versions, except for the cost attribute, all choice sets were equal. RESULTS: The cost coefficient was statistically significantly higher in the WTP format. Marginal WTA was statistically significantly higher than marginal WTP for the attributes accuracy and follow-up. Disparity was higher in the high educational (as proxy for income) group. We did not find proof of an experience endowment effect. Implementing the new intervention would only be recommended when using WTP. CONCLUSIONS: WTA exceeds WTP, also in a discrete choice experiment. As this affects monetary valuations, more research on when to use a payment or a discount in the cost attribute is needed before discrete choice results can be used in cost-benefit analyses.

Patient preferences for direct hearing aid provision by a private dispenser. A discrete choice experiment.

OBJECTIVES: Our objective was to elicit patient preferences for transferring elements of hearing aid provision from the medical sector [Ear Nose and Throat (ENT) specialists and audiological centers] to private hearing aid dispensers, and to understand the trade-offs between different elements of hearing aid provision. DESIGN: A discrete choice experiment was administered from 150 hearing-impaired persons in the Netherlands. Mean age was 71 (range 18-95) and 57% were male. RESULTS: Participants preferred the initial assessment at the dispenser, higher accuracy in identifying persons in need of medical care, shorter duration of the total hearing aid provision, and a follow-up at the ENT specialist. They required compensation of at least euro 17 per 2 mo extra duration, euro 54 for an initial assessment at the ENT specialist, euro 119 per 10% decrease in accuracy, and euro 227 to forgo the follow-up at the ENT specialist. Preferences were influenced by sex, age, educational level, and experience with hearing aid provision. CONCLUSIONS: Hearing-impaired persons are receptive to transferring elements of hearing aid provision from the medical sector to private dispensers. Although safety and efficiency issues should also be considered, from the present study we can conclude that in the organization of hearing aid provision hearing-impaired persons prefer an initial assessment at a private dispenser when the dispenser is at least 95% as accurate as the ENT specialist, and prefer a follow-up visit at the ENT specialist.

Effects of folic acid supplementation on hearing in older adults: a randomized, controlled trial.

BACKGROUND: Age-related hearing loss is a common chronic condition of elderly persons. Low folate status has been associated with poor hearing. OBJECTIVE: To determine whether folic acid supplementation slows age-related hearing loss. DESIGN: Double-blind, randomized, placebo-controlled trial conducted from September 2000 to December 2004. SETTING: The Netherlands. PARTICIPANTS: 728 older men and women recruited from municipal and blood bank registries with plasma total homocysteine concentrations 13 micromol/L or greater serum and vitamin B12 concentrations 200 pmol/L or greater at screening, and no middle ear dysfunction, unilateral hearing loss, or pathologic ear conditions unrelated to aging. INTERVENTION: Daily oral folic acid (800 microg) or placebo supplementation for 3 years. MEASUREMENTS: 3-year change in hearing thresholds, assessed as the average of the pure-tone air conduction thresholds of both ears of the low (0.5-kHz, 1-kHz, and 2-kHz) and high (4-kHz, 6-kHz, and 8-kHz) frequencies. RESULTS: Initial median hearing thresholds were 11.7 dB (interquartile range, 7.5 to 17.5 dB) for low frequencies and 34.2 dB (interquartile range, 22.5 to 50.0 dB) for high frequencies. Sixteen participants (2%) were lost to follow-up. After 3 years, thresholds of the low frequencies increased by 1.0 dB (95% CI, 0.6 to 1.4 dB) in the folic acid group and by 1.7 dB (CI, 1.3 to 2.1 dB) in the placebo group (difference, -0.7 dB [CI, -1.2 to -0.1 dB]; P = 0.020). Folic acid supplementation did not affect the decline in hearing high frequencies. LIMITATIONS: The strict criterion for participation on the basis of serum homocysteine concentrations limits extrapolation to the general population. Folic acid fortification of food was prohibited in the Netherlands during the study, so baseline folate levels in participants were about half of those found in the U.S. population. CONCLUSIONS: Folic acid supplementation slowed the decline in hearing of the speech frequencies associated with aging in a population from a country without folic acid fortification of food. The effect requires confirmation, especially in populations from countries with folic acid fortification programs. Clinicaltrials.gov identifier: NCT00110604.

Potential barriers and facilitators for implementation of an integrated care pathway for hearing-impaired persons: an exploratory survey among patients and professionals.

BACKGROUND: Because of the increasing costs and anticipated shortage of Ear Nose and Throat (ENT) specialists in the care for hearing-impaired persons, an integrated care pathway that includes direct hearing aid provision was developed. While this direct pathway is still under investigation, in a survey we examined expectations and potential barriers and facilitators towards this direct pathway, of patients and professionals involved in the pathway. METHODS: Two study populations were assessed: members of the health professions involved in the care pathway for hearing-impaired persons (general practitioners (GPs), hearing aid dispensers, ENT-specialists and clinical audiologists) and persons with hearing complaints. We developed a comprehensive semi-structured questionnaire for the professionals, regarding expectations, barriers, facilitators and conditions for implementation. We developed two questionnaires for persons with hearing complaints, both regarding evaluations and preferences, and administered them after they had experienced two key elements of the direct pathway: the triage and the hearing aid fitting. RESULTS: On average GPs and hearing aid dispensers had positive expectations towards the direct pathway, while ENT-specialists and clinical audiologists had negative expectations. Professionals stated both barriers and facilitators towards the direct pathway. Most professionals either supported implementation of the direct pathway, provided that a number of conditions were satisfied, or did not support implementation, unless roughly the same conditions were satisfied. Professionals generally agreed on which conditions need to be satisfied. Persons with hearing complaints evaluated the present referral pathway and the new direct pathway equally. Many, especially older, participants stated however that they would still visit the GP and ENT-specialist, even when this would not be necessary for reimbursement of the hearing aid, and found it important that the ENT-specialist or Audiological Centre evaluated their hearing aid. CONCLUSION: This study identified professional concerns about the direct pathway for hearing-impaired persons. Gaps exist in expectations amongst professions. Also gaps exist between users of the pathway, especially between age groups and regions. Professionals are united in the conditions that need to be fulfilled for a successful implementation of the direct pathway. Implementation on a regional level is recommended to best satisfy these conditions.

Association of folate with hearing is dependent on the 5,10-methylenetetrahdyrofolate reductase 677C-->T mutation.

Vascular disease and its risk factors have been associated with the age-related hearing loss. We examined the association of elevated plasma homocysteine and its determinants with hearing levels. Pure-tone air conduction thresholds in 728 individuals with sensorineural hearing loss were not associated with homocysteine, erythrocyte folate and Vitamin B6. Low concentrations of serum folate and Vitamin B12 were associated with better hearing. When folate status was below the median, 5,10-methylenetetrahydrofolate reductase (MTHFR) 677TT homozygotes had similar hearing levels to subjects with a C allele. However, when folate status was above the median, MTHFR 677TT homozygotes had on an average 5 dB (p = 0.037) and 2.6 dB (p = 0.021) lower PTA-high and PTA-low hearing thresholds, respectively, than the subjects with a 677C allele. The relationship between serum folate and hearing thresholds appeared to be dependent on MTHFR 677 genotype (CC, r = 0.13, p = 0.034; TT, r = -0.10, p = 0.291). This supports the hypothesis that a greater one-carbon moiety commitment to de novo synthesis of nucleotides and an increase in formyl-folate derivatives relative to methyl-folate derivatives is protective for hearing.

Intrauterine Lipopolysaccharide-Induced Chorioamnionitis in a Sheep: Does It Affect the Auditory System?

BACKGROUND: Fetal exposure to in utero inflammation such as chorioamnionitis is related to central nervous system injury. We hypothesized that chorioamnionitis can provoke inflammatory changes in the perilymph and alter hearing outcome. METHODS: Pregnant ewes were randomized into 2 groups: intrauterine injection with lipopolysaccharide (LPS; n = 19) or saline (n = 21). In the first experiment, fetal perilymph samples were taken for cytokine analysis. In the second experiment, consecutive bone-conducted auditory brain stem responses were obtained from 1 to 7 months after birth. RESULTS: Perilymph samples showed a significant elevation in interleukin 8 in the LPS group. Auditory brain stem response analysis demonstrated higher response thresholds and a prolongation of absolute peak V and interpeak intervals I to V and III to V in the LPS group compared to sham treatment. CONCLUSION: Our study confirms the hypothesis that an intrauterine inflammation by LPS can result in a fetal perilymphatic inflammatory response and functional impaired hearing outcomes after birth in a sheep model.