Stroke risk in African Americans with subclinical auditory dysfuntion evidenced by Distortion Product Otoacoustic Emissions: the Jackson heart study.

Objective: Distortion product otoacoustic emissions (DPOAEs) are sensitive to early indices of cochlear pathology. Pathology to the cochlea is in part mediated by ischaemic related mechanisms. We propose that DPOAEs may provide an objective measure of cardiovascular risk.Design: Cross-sectional.Study sample: The relationships between stroke risk and DPOAEs of 1,107 individuals from the Jackson Heart Study (JHS), an all-African-American cohort, were assessed. Linear regression models were used for analysis among all participants and delimited to normal hearing, defined as either a pure-tone threshold average of 500, 1000, 2000, and 4000 Hz (PTA4) ≤ 25 dBHL or pure-tone thresholds for all individual tested frequencies for each ear (500, 1000, 2000, 4000, and 8000 Hz) ≤ 25 dBHL.Results: We observed a significant inverse relationship between DPOAE amplitudes and stroke risk scores in the pooled cohort and in the subgroups with normal hearing defined by pure tone thresholds. Participants in the high-risk group had significantly lower DPOAE amplitudes than those in the low stroke risk group.Conclusions: Our results indicate that auditory dysfunction as measured by DPOAEs are related to stroke risk. Further prospective studies are needed to determine if DPOAEs could be used as a predictive tool for cardiovascular disease.

Relationship of stroke risk and hearing loss in African Americans: The Jackson Heart Study.

OBJECTIVES/HYPOTHESIS: To evaluate the relationships among measures of stroke risk and hearing in an African American cardiovascular study cohort. STUDY DESIGN: Prospective cohort study. METHODS: The relationships between stroke risk profiles and hearing of 1,107 individuals from a cohort of African Americans were assessed. Several different hearing pure-tone averages (PTAs) were constructed representing different frequency regions of hearing, namely PTA low, PTA mid, and PTA high. Stroke risk profiles were calculated using validated 10-year cardiovascular disease risk scores. Gamma regression analyses were performed for each PTA given as a continuous variable with change in stroke risk score. Logistic regression analyses, presented as odds ratios, were performed with hearing loss defined as any PTA >25 dB hearing level. Stratification models were analyzed for age quarterlies and among sex. RESULTS: Single unit increases of stroke risk percentage were found to be predictive of increases in all PTA threshold levels in gamma regression analyses for the overall pooled sample. The relationship was influenced by age, where fewer significant relationships were observed at higher ages. When analyzed with respect to stroke risk categories, using low risk as the reference group, there was found to be a significant association between stroke risk and hearing loss in the medium- and high-risk groups, with a stronger relationship in the high-risk group for all PTA threshold levels. CONCLUSIONS: This study provides evidence that stroke risk has a positive predictive relationship with hearing pure-tone threshold. LEVEL OF EVIDENCE: 2b. Laryngoscope, 128:1438-1444, 2018.

Monopolar cautery and adverse effects on cochlear implants.

IMPORTANCE: The use of monopolar cautery has been widely regarded as a contraindication in the setting of a cochlear implant because of presumed risk to the implant device. There are very limited data to support this contraindication. OBJECTIVES: (1) To evaluate the effects of monopolar cautery on cochlear implant devices. (2) To determine whether monopolar cautery changes the endocochlear temperature in an implanted cochlea. DESIGN: Sixteen cochlear implants from 3 manufacturers (Advanced Bionics LLC, Cochlear Americas Ltd, and Med-El Ltd) were implanted into 2 unembalmed, fresh cadavers. Monopolar cautery was applied to either the tongue or abdomen at coagulation settings of 10 W or 50 W for 30 minutes. Impedance and integrity testing were performed before, during, and after 30 minutes of cautery. The temperature in the endocochlear perilymph was measured during cautery. After explantation, devices were returned to the manufacturer for an in-depth "failure" analysis according to each manufacturer's current protocol evaluating explanted devices. SETTING: Basic science laboratory, tertiary medical center. PARTICIPANTS: Cadaveric study. INTERVENTION: Application of monopolar cautery to implanted cochlear implants in a cadaveric model. MAIN OUTCOME AND MEASURE: (1) Changes to the implanted devices either during electrocautery or following failure analysis. (2) Changes in the intracochlear temperature. RESULTS: No change in impedance, integrity testing, or failure analysis occurred at any cautery setting when applied to either the oral cavity or abdomen. The temperature of the cochlea did not increase with up to 30 minutes of cautery at a setting of 50 W. Comprehensive device analysis did not show any evidence of device damage at the conclusion of the study. CONCLUSIONS AND RELEVANCE: Monopolar cautery did not produce detectible damage to any of the cochlear implant devices or produce detectible temperature change in the cochlea at low or high levels of cautery in the oral cavity in this experimental model.