Hearing Assessment and Rehabilitation for People Living With Dementia.

Hearing impairment commonly co-occurs with dementia. Audiologists, therefore, need to be prepared to address the specific needs of people living with dementia (PwD). PwD have needs in terms of dementia-friendly clinical settings, assessments, and rehabilitation strategies tailored to support individual requirements that depend on social context, personality, background, and health-related factors, as well as audiometric HL and experience with hearing assistance. Audiologists typically receive limited specialist training in assisting PwD and professional guidance for audiologists is scarce. The aim of this review was to outline best practice recommendations for the assessment and rehabilitation of hearing impairment for PwD with reference to the current evidence base. These recommendations, written by audiology, psychology, speech-language, and dementia nursing professionals, also highlight areas of research need. The review is aimed at hearing care professionals and includes practical recommendations for adapting audiological procedures and processes for the needs of PwD.

ABR in newborns: effects of electrode configuration, stimulus rate, and EEG rejection levels on test efficiency.

OBJECTIVE: This study investigated the effect of electrode configuration, stimulus rate, and EEG rejection level on the efficiency of ABR testing in babies. DESIGN: ABR to click stimuli at 40 dB nHL were simultaneously recorded from two electrode configurations, ipsilateral mastoid to high forehead (Mi-Fh) and nape to high forehead (N-Fh), with two EEG rejection levels (± 5 µV and ± 10 µV). Stimulus rates were between 39.1 and 69.1 per second. Efficiency was measured by confidence in the ABR for a given test time. STUDY SAMPLE: Thirty babies who had passed a targeted newborn hearing screen with ABR thresholds ≤ 40 dB nHL. RESULTS: The N-Fh configuration, as expected, gave on average a larger response amplitude compared to the Mi-Fh configuration but was only marginally significantly better in terms of test efficiency. There was no significant effect of stimulus rate on test efficiency between 39.1/s and 59.1/s. The lower ± 5 µV EEG rejection level was more test efficient. CONCLUSIONS: This study provides some evidence that, for ABR threshold testing in babies, alternatives of ipsilateral mastoid or nape electrode and a range of stimulus rates have little or no effect on test efficiency. The results support the use of low EEG rejection limits.

Intra and intersubject variability in auditory steady-state response amplitude with high modulation rates to 1000 Hz amplitude modulated and tone pip stimuli.

OBJECTIVE: This study set out to provide further information on how high modulation/stimulus rates affect the auditory steady-state response (ASSR) amplitude for a 1000-Hz tone, and how this effect varies between individuals. Both sinusoidal amplitude modulated tones and tone pip stimuli were investigated. DESIGN: Modulation/stimulus rates were 70, 80, and 90 Hz and the peak to peak stimulus levels were matched for the two different types of stimuli, at 90.5 dBSPLppe. STUDY SAMPLE: The study was carried out on fourteen normally-hearing adults (9 males and 5 females) RESULTS: Overall the ASSR amplitude to the two types of stimuli was similar. In general there was an increasing response amplitude between rates of 70 and 90 Hz; The relationship between the amplitude of the response and the modulation /stimulus rate varied considerably between subjects. CONCLUSIONS: Optimum stimulus rates based on group data may not give the best rate in a significant proportion of subjects. Currently tone pip ABR is the primary method used in assessing hearing in babies. Finding a way of avoiding suboptimal stimulus rates for '80-Hz' ASSR in babies will improve the likelihood of ASSR being seen as an alternative.

The effect of varying stimulus phase between frequency and amplitude modulation on auditory steady-state responses in neonates.

OBJECTIVE: To compare auditory steady-state responses (ASSRs) to air-conducted amplitude, frequency, and mixed modulated stimuli (AM, FM, and MM, respectively) in neonates. DESIGN: Multiple ASSRs to AM, FM, and MM to 0.5, 1, 2, and 4 kHz tones modulated between 0.078 and 0.092 kHz were recorded and compared. MM phase settings across the cycle at 45° intervals were used and optimum phase settings were predicted using a sinusoidal model. STUDY SAMPLE: Twenty neonates with click ABR thresholds of ≤ 40 dB nHL. RESULTS: ASSR amplitudes were significantly larger to AM than FM stimuli. MM phase setting had a significant effect on amplitude at 1, 2, and 4 kHz but not 0.5 kHz. MM phase settings (± 95% confidence intervals) of 276° (± 9.5°) and 270° (± 19.1°) were predicted for 1 and 2 kHz, respectively. The 0.5 and 4 kHz data were not sufficient to model any effect of phase. MM and AM response latencies increased with decreasing carrier frequency. Some MM response latencies were significantly different from AM response latencies, however no consistent trend was apparent. Test times were significantly affected by phase setting. CONCLUSIONS: MM phase settings have a significant effect on ASSR response amplitude and latencies in neonates.

Evolution of pulmonary inflammation and nutritional status in infants and young children with cystic fibrosis.

INTRODUCTION: Improved nutrition is the major proven benefit of newborn screening programmes for cystic fibrosis (CF) and is associated with better clinical outcomes. It was hypothesised that early pulmonary inflammation and infection in infants with CF is associated with worse nutrition. METHODS: Weight, height and pulmonary inflammation and infection in bronchoalveolar lavage (BAL) were assessed shortly after diagnosis in infants with CF and again at 1, 2 and 3 years of age. Body mass index (BMI) was expressed as z-scores. Inflammatory cells and cytokines (interleukin 1ß (IL-1ß), IL-6, IL-8 and tumour necrosis factor α (TNFα)), free neutrophil elastase activity and myeloperoxidase were measured in BAL. Mixed effects modelling was used to assess longitudinal associations between pulmonary inflammation, pulmonary infection (Staphylococcus aureus and Pseudomonas aeruginosa) and BMI z-score after adjusting for potential confounding factors. RESULTS: Forty-two infants were studied (16 (38%) male; 39 (93%) pancreatic insufficient); 36 were diagnosed by newborn screening (at median age 4 weeks) and six by early clinical diagnosis (meconium ileus). Thirty-one (74%) received antistaphylococcal antibiotics. More than two-thirds were asymptomatic at each assessment. Mean BMI z-scores were -1.5 at diagnosis and 0.5, -0.2 and -0.1 at 1, 2 and 3 years, respectively. Neutrophil elastase and infection with S aureus were associated with lower BMI, whereas age (p=0.01) and antistaphylococcal antibiotics (p=0.013) were associated with increased BMI. On average, each log(10) increase in free neutrophil elastase activity was associated with a 0.43 (95% CI 0.06 to 0.79) reduction in BMI z-score. DISCUSSION: Early nutritional status is associated with the underlying pulmonary pathophysiology in CF, and better understanding of these relationships is required. Studies are required to assess whether interventions can decrease pulmonary inflammation and improve nutrition. Early surveillance will enable such targeted interventions with the aim of improving these important clinical outcomes.

Effect of varying phase between frequency and amplitude modulation on bone conduction auditory steady state responses.

OBJECTIVES: Auditory steady state response (ASSR) testing provides a means to objectively estimate hearing levels in newborns and adults for whom behavioral tests prove difficult. When testing these patient groups, it is preferable that clear responses to both air and bone conduction stimuli are obtained in a short amount of time. Much of the literature addressing ASSRs, such as investigations of stimulus and recording parameters, have focused on air conduction ASSRs. The aim of this investigation was to study the amplitudes, latencies, and test times of bone conduction ASSRs elicited using amplitude- (AM), frequency- (FM), and mixed-modulated (MM) stimuli and provide suggestions for optimum recording parameters. DESIGN: Bone and air conduction multiple ASSRs were recorded from two groups of 20 normal-hearing adults using the Multiple Auditory Steady State Response research system. AM, FM, and MM sinusoidal tones were used (0.5-, 1-, 2-, and 4-kHz carrier frequencies), which were modulated between 78 and 92 Hz. AM depth was 100% and FM depth was 20%. ASSR amplitudes and latencies (calculated using the "preceding cycles" technique) were analyzed for MM phase settings across the cycle from 0° at 45° intervals and compared with AM responses. Optimum phase settings for bone and air conduction ASSRs were calculated using a sinusoidal model based on the amplitude data. RESULTS: Similar effects of stimulus type and carrier frequency were observed for bone and air conduction ASSRs. AM responses were larger in amplitude compared with FM responses. MM (at all phase settings tested) and AM response latencies increased with decreasing carrier frequency. MM phase setting had a significant (p < 0.01) sinusoidal effect on ASSR amplitudes, compared with AM responses, at 1, 2, and 4 kHz but not 0.5 kHz for air conduction and 1 and 2 kHz but not 0.5 and 4 kHz for bone conduction. Using a sinusoidal function to model this effect, MM phase settings (±95% confidence intervals) of 318° (295 to 350°) and 295° (290 to 310°) are predicted to evoke the largest responses for bone conduction ASSRs at 1 and 2 kHz, respectively. Phase settings of 293° (285 to 310°), 300° (280 to 310°), and 280° (255 to 330°) are predicted for air conduction ASSRs at 1, 2, and 4 kHz, respectively. MM phase setting had little effect on estimated latency. Test times were significantly (p < 0.01) affected by phase setting with both increases and decreases being observed. Test times for ASSRs at 1, 2, and 4 kHz could be significantly reduced if the estimated optimum phase settings are used. CONCLUSIONS: Different stimuli can significantly affect the amplitudes of bone conduction ASSRs. These effects are similar to those observed for air conduction ASSRs. MM stimuli with specific phase settings evoke larger bone conduction ASSRs compared with AM and FM stimuli alone, and calculations show that the time taken to obtain these responses is reduced. Implementation of the suggested optimum settings will promote efficient collection of bone conduction, and indeed air conduction, ASSR data.

Bone conduction auditory steady state response: investigations into reducing artifact.

OBJECTIVES: Auditory steady state responses (ASSRs) can be reliably recorded in sleeping neonates and can be used to estimate hearing thresholds in individuals with normal or impaired hearing. However, artifactual responses can contaminate recordings, particularly when recording bone conduction ASSRs. The aim of this investigation was to study the presence of electromagnetic artifact in bone conduction ASSRs and to investigate methods of reducing the amplitude of the artifact. DESIGN: Using a simulation of a patient, ASSR recordings were obtained to multiple frequency bone-conducted stimuli using the research MASTER system. ASSR stimuli were sinusoidal tones with the carrier frequencies 500, 1000, 2000, and 4000 Hz that were 100% amplitude modulated at 83, 87, 91, and 95 Hz, respectively. After the assessment of different equipment layouts, the effects of (1) altering the analog-to-digital conversion rates and (2) screening the transducer cable and B-71 transducer and connecting the screens to ground were investigated. RESULTS: For ASSR recordings, artifacts were observed at the modulation rates of the 1000-, 2000-, and 4000-Hz carrier frequencies. As expected, the artifact was proportional to stimulus intensity and was observed when using sampling rates of 1000 and 2000 Hz but not 1250 and 1600 Hz. Altering the electrode lead/transducer cable layout and orientation of the B-71 transducer significantly affected the amplitude of the artifact. Screening of the B-71 transducer and cable and connecting the screens to ground reduced the amplitude of the artifact to a level that was not significantly above background noise. A mu-metal screen had a significantly greater effect than aluminum or copper. CONCLUSIONS: If stimulus artifact is present in the recorded EEG, for certain choices of carrier frequency and sampling rate it is possible to record artifactual signals at the same modulation rates as those used to elicit ASSRs. This is problematic as the artifact may then be misinterpreted as an ASSR response. The results from this study have demonstrated that careful attention to equipment layout, choice of sampling rate, using grounded screens to screen the B-71 transducer and transducer cable can all be effective in reducing the level of stimulus artifact.

Lung function in infants with cystic fibrosis diagnosed by newborn screening.

RATIONALE: Progressive lung damage in cystic fibrosis (CF) starts in infancy, and early detection may aid preventative strategies. OBJECTIVES: To measure lung function in infants with CF diagnosed by newborn screening and describe its association with pulmonary infection and inflammation. METHODS: Infants with CF (n = 68, 6 weeks to 30 months of age) and healthy infants without CF (n = 49) were studied. Forced vital capacity, FEV(0.5), and forced expiratory flows at 75% of exhaled vital capacity (FEF(75)) were measured using the raised-volume rapid thoracoabdominal compression technique. Forty-eight hours later, infants with CF had bronchoalveolar lavage (BAL) for assessment of pulmonary infection and inflammation. MEASUREMENTS AND MAIN RESULTS: In the CF group, the deficit in FEV(0.5) z score increased by -0.77 (95% confidence interval, -1.14 to -0.41; P < 0.001) with each year of age. The mean FEV(0.5) z score did not differ between infants with CF and healthy control subjects less than 6 months of age (-0.06 and 0.02, respectively; P = 0.87). However, the mean FEV(0.5) z score was lower by 1.15 in infants with CF who were older than 6 months of age compared with healthy infants (P < 0.001). FVC and FEF(75) followed a similar pattern. Pulmonary infection and inflammation in BAL samples did not explain the lung function results. CONCLUSIONS: Lung function, measured by forced expiration, is normal in infants with CF at the time of diagnosis by newborn screening but is diminished in older infants. These findings suggest that in CF the optimal timing of therapeutic interventions aimed at preserving lung function may be within the first 6 months of life.

Click-evoked otoacoustic emissions (CEOAEs) recorded from neonates under 13 hours old using conventional and maximum length sequence (MLS) stimulation.

Maximum length sequence (MLS) stimulation allows click evoked otoacoustic emissions (CEOAEs) to be averaged at very high stimulation rates. This enables a faster reduction of noise contamination of the response, and has been shown to improve the signal-to-noise ratio (SNR) of CEOAEs recorded from adult subjects. This study set out to investigate whether MLS averaging can enhance the SNR of CEOAEs recorded in newborns within the first day after birth, and so improve the pass rates for OAE screening in this period, when false alarm rates are very high. CEOAEs were recorded in a neonatal ward from 57 ears in 37 newborns ranging from 6 to 13h old, using both conventional (50/s) and high rate (5000/s) MLS averaging. SNR values and pass rates were compared for responses obtained within equal recording times at both rates. MLS averaging produced an SNR improvement of up to 3.8dB, with the greatest improvement found in higher frequency bands. This SNR advantage resulted in pass rate improvement between 5% and 10%, depending on pass criterion. A significant effect of age was found on both SNR and pass rate, with newborns between 6 and 10h old showing significantly lower values than those tested between 10 and 13h after birth, as well as a much greater improvement due to MLS averaging. The findings show that MLS averaging can reduce false alarm rates by up to 15% in very young neonates in a neonatal ward setting.