Cardiovascular Risk and Hearing Loss, Are They Connected? Results from the Busselton Healthy Ageing Study

Background: Cardiovascular disease and hearing loss are commonly associated in adults. Reduced blood supply to the stria vascularis of the cochlea may lead to impairment of inner-ear function. We aim to show if a cardiovascular risk score is associated with hearing loss. Methods: The Busselton Healthy Ageing Study is a cross-sectional study conducted between 2010-2015. Overall, 4,877 participants invited from a random electoral roll were included in the analysis. Hearing was assessed by air conduction audiometry, and summarised as mid-frequency (500, 1000, 2000, 4000 Hz), low-frequency (250, 500, 1000 Hz) and high-frequency (4000, 8000 Hz) averages. Cardiovascular risk factors were assessed by questionnaire and objective measurements, and used to calculate the 10-year Framingham Risk Score (FRS). Results: Participants were aged 45 to 69 years, with 54% being female. Age, sex and family history of hearing impairment were strong determinants of hearing loss. After adjusting for these, all audiometric averages showed a graded association with the FRS. Participants with a FRS >20 were 2.75 times (95% CI 1.62-3.89) more likely to have increased mid-frequency average, 3.17 times (95% CI 2.16-4.17) more likely to have elevated low-frequency average, and 3.37 times (95% CI 1.40-5.34) more likely to have elevated high-frequency average compared to those with a FRS of 0 to 5 (trend p < 0.001 for all). Conclusions: A high cardiovascular risk score is associated with hearing loss among middle-aged men and women. If future studies establish a causative link, then targeting cardiovascular risk factors may play a role in preventing hearing loss.