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In animals, noise exposures that produce robust temporary threshold shifts (TTS) can produce immediate damage to afferent synapses and long-term degeneration of low spontaneous rate auditory nerve fibers. This synaptopathic damage has been shown to correlate with reduced auditory brainstem response (ABR) wave-I amplitudes at suprathreshold levels. The perceptual consequences of this "synaptopathy" remain unknown but have been suggested to include compromised hearing performance in competing background noise. Here, we used a modified startle inhibition paradigm to evaluate whether noise exposures that produce robust TTS and ABR wave-I reduction but not permanent threshold shift (PTS) reduced hearing-in-noise performance. Animals exposed to 109 dB SPL octave band noise showed TTS >30 dB 24-h post noise and modest but persistent ABR wave-I reduction 2 weeks post noise despite full recovery of ABR thresholds. Hearing-in-noise performance was negatively affected by the noise exposure. However, the effect was observed only at the poorest signal to noise ratio and was frequency specific. Although TTS >30 dB 24-h post noise was a predictor of functional deficits, there was no relationship between the degree of ABR wave-I reduction and degree of functional impairment.

Objectives To understand measures of frailty among preoperative patients and explain how these can predict perioperative outcomes among patients with head and neck cancer. Study Design Retrospective cross-sectional case series with chart review. Setting Academic tertiary medical center. Subjects and Methods A retrospective review was performed of patients presenting to an academic hospital following a surgical procedure for a head and neck cancer diagnosis. Charts were queried for preoperative medical diagnoses to calculate 2 frailty scores: the American College of Surgeons National Surgical Quality Improvement Program modified frailty index and the Johns Hopkins Adjusted Clinical Groups frailty index. The American Society of Anesthesiologists classification system was also analyzed as a predictor. Primary outcomes were mortality, 30-day readmission, and length of stay. Perioperative complications and discharge disposition were also evaluated. Results A total of 410 charts were queried between January 2014 and December 2017. Mortality was 11%; mean ± SD length of stay was 7.4 ± 5.5 days; and the readmission rate was 17%. The modified frailty index score significantly increased the odds of mortality (odds ratio = 1.475, P = .012) and readmission (odds ratio = 1.472, P = .004), the length of stay (relative risk = 1.136, P = .001), and the number of perioperative complications. The American Society of Anesthesiologists classification was also significantly associated with poor outcomes, including readmission, length of stay, and perioperative complications. The Adjusted Clinical Groups index was not a significant predictor of outcomes in this study population. Conclusions This study demonstrated a significant increase in poor perioperative outcomes and mortality among patients with head and neck cancer and increased frailty, as measured by the modified frailty index.

Background Human hearing is sensitive to sounds from as low as 20 Hz to as high as 20,000 Hz in normal ears. However, clinical tests of human hearing rarely include extended high frequency (EHF) threshold assessments, at frequencies extending beyond 8,000 Hz. EHF thresholds have been suggested for use monitoring the earliest effects of noise on the inner ear, although the clinical utility of EHF threshold testing is not well established for this purpose. Purpose The primary objective of this study was to determine if EHF thresholds in healthy, young adult college students vary as a function of recreational noise exposure. Research Design A retrospective analysis of a laboratory database was conducted; all participants with both EHF threshold testing and noise history data were included. The potential for “pre-clinical” EHF deficits was assessed based on the measured thresholds, with the noise surveys used to estimate recreational noise exposure. Study Sample EHF thresholds measured during participation in other ongoing studies were available from 87 subjects (34 male and 53 female); all participants had hearing within normal clinical limits (≤25 HL) at conventional frequencies (0.25 to 8 kHz). Results EHF thresholds closely matched standard reference thresholds [ANSI S3.6 (1996) Annex C]. There were statistically reliable threshold differences in subjects that used music players, with 3–6 dB worse thresholds at the highest test frequencies (10–16 kHz) in participants that reported long-term music player device use (longer than 5 years), or higher listening levels during music player use. Conclusions It should be possible to detect small changes in high frequency hearing for patients/participants that undergo repeat testing at periodic intervals. However, the increased population-level variability in thresholds at the highest frequencies will make it difficult to identify the presence of small but potentially important deficits in otherwise normal hearing individuals that do not have previously established baseline data.

Dietary vitamin A and vitamin E intake were significantly associated with the prevalence of hearing loss. However, dietary antioxidant intake did not increase the risk of incident hearing loss. Further large, prospective studies are warranted to assess these relationships in older adults.

Objective A significant relationship between dietary nutrient intake and susceptibility to acquired hearing loss is emerging. Variability in the outcomes across studies is likely related to differences in the specific metrics used to quantify nutrient intake and hearing status. Most studies have used single nutrient analysis. Although this analysis is valuable, interactions between nutrients are increasingly recognized and could modify modeling of single nutrient effects. Therefore, we examined the potential relationship between diet and hearing using a metric of overall dietary quality. Design This cross-sectional analysis was based on Healthy Eating Index data and audiological thresholds. Study sample Data for adults between the ages of 20 to 69 years of age were drawn from the National Health and Nutrition Examination Survey, 1999–2002. Results Controlling for age, race/ethnicity, sex, education, diabetes, and noise exposure, we found a significant negative relationship (Wald F = 6.54, df = 4, 29; p ≤ 0.05) between dietary quality and thresholds at higher frequencies, where higher dietary quality was associated with lower hearing thresholds. There was no statistically significant relationship between dietary quality and threshold sensitivity at lower frequencies. Conclusions The current findings support an association between healthier eating and lower high frequency thresholds in adults.

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These data suggest that nutrients with known roles in redox homeostasis and vascular health are associated with auditory function measures in a human population. Further investigation is warranted to determine direct and indirect influences of dietary intake on measures of auditory function and to explore which nutrients/nutrient combinations are predictive of SNHL.