To investigate the effects of cardiovascular risk factors on hearing loss by vascular damage, such as in atherosclerosis.

This study was conducted as a part of a study for the health effects of air-craft noise from 13 July 2005 to 13 January 2006. In this study 810 residents were selected from 13 villages in Pyeongteck City. Participants in this study were stratified by gender. Individuals, who had conductive hearing loss, were excluded form this investigation. Cardiovascular risk factors were divided into medical risk factors (mean arterial pressure (MAP), blood glucose, triglyceride) and behavioral risk factors (smoking, alcohol). The degree of atherosclerosis was determined by aPWV. Pure tone air conduction hearing thresholds were obtained at frequencies of 1000 and 4000 Hz. As for statistic data analysis, multiple linear regression models were used to evaluate the relationship between factors on hearing loss and aortic pulse wave velocity. Structural Equation Modeling was used to analyze the relationship between factors.

According to multiple linear regression models among males, age, aircraft noise, aPWV were associated with hearing loss. In females, age and aircraft noise were associated with hearing loss. Thus cardiovascular risk factors were not directly involved in hearing loss. However, cardiovascular risk factors such as alcohol, MAP in males and MAP, blood glucose in females were statistically significant (p<0.05) on aPWV according to multiple linear regression modeling. According to analysis of structural equation modeling, an indirect relationship was observed between cardiovascular risk factors and hearing loss by atherosclerosis, which was measured by aPWV. In males, medical risk factors were significantly associated with atherosclerosis (beta±SE: 0.07±0.03, p=0.03). Atherosclerosis was also associated with hearing loss (beta±SE: 2.01±0.89, p=0.03). In females, medial risk factors was significantly associated with atherosclerosis (beta±SE: 0.08±0.02, p=0.00), but atherosclerosis was not significantly associated with hearing loss.

Although noise exposure is a known major threat to hearing loss, understanding of cardiovascular risk factors associated with hearing loss also take a significant role in preventing hearing loss. Therefore, scrutinization of the etiologic factors for hearing disability may introduce a detailed strategy to abate the prevalence of hearing loss.