Title: Cardiometabolic risk factors, hearing loss, and cochlear health

Bio: Rachael R. Baiduc, PhD, MPH is associate professor of speech, language and hearing sciences. She completed her doctoral studies and MPH at Northwestern University and joined the CU Boulder faculty in 2016. She is director the Hearing Epidemiology and Research Diagnostics laboratory, which focuses on hearing health and its relation to overall health, particularly cardiometabolic risk factors. Her work includes epidemiological studies and laboratory-based research using behavioral and physiological assessment of the auditory system. Dr. Baiduc's research has been funded by the American Hearing Research Foundation, CU Boulder, the Hearing Health Foundation, and currently, the NIH (NIDCD). 

Abstract: 

Hearing loss, diabetes, and hypertension (HTN) are prevalent chronic conditions associated with substantial morbidity. Though animal studies suggest the cochlea is irreversibly compromised in persons with HTN and diabetes, research is mixed regarding the association between cochleopathy cardiometabolic risk factors and there are limited measures of cochlear health in humans with these conditions. Additional complexity is added due to nonmodifiable (e.g., age) and modifiable (e.g., noise exposure, diet, smoking) factors. This talk will explore three studies in which we characterize associations between auditory health and cardiometabolic risk factors. We hypothesized HTN and diabetes would be associated with hearing loss and compromised outer hair cell function. The studies discussed in this talk will include (1) audiometric and cardiometabolic health data from electronic medical records (EMRs, n=6332), (2) audiometric and otoacoustic emission data from the all-Black Jackson Heart (JHS) study (n=1106), and (3) emerging findings on HTN and cochlear health from an ongoing laboratory-based study (n=~200). All three studies used puretone audiometry to determine hearing sensitivity. The JHS and laboratory-based studies also assayed the cochlea using distortion product otoacoustic emissions (DPOAEs), a noninvasive test of outer hair cell function. Logistic and linear regression were employed to determine associations between auditory outcomes and cardiovascular disease risk factors (e.g., smoking, HTN, diabetes, high cholesterol, total CVD risk load) accounting for potential confounders such as age, sex, and noise exposure. Analysis of the JHS data revealed an association between diabetes and hearing loss, but no significant relationship was observed between CVD risk factors and cochlear health. Results from the EMR study were sex specific. For males, diabetes, hypertension, smoking, and ≥2 major CVD risk factors were associated with hearing loss. For females, diabetes, smoking, and ≥2 major CVD risk factors were significant risk factors. Together, results of these two studies underscored the need for more research on the HTN-hearing loss association, work that is currently ongoing in the laboratory. Current efforts are focused on elucidating the cochlear signature of HTN and exploring the potential role of race. Preliminary findings from this ongoing work will be presented.