Comparison of Balance Between Young Adults With and Without Hearing Impairment

Abstract

Damaged vestibular system is one of the major causes of hearing impairment (HI), affects 1 to 6/1000 newborns in the United States, and is associated with balance impairment. Balance deficits may interfere with the development of motor skills. Studies have shown that balance in children with HI improves until adolescence. Few studies have investigated whether balance is impaired in young adults with HI and there results are inconsistent. PURPOSE: To compare balance between young adults with and without HI. METHODS: A total of 35 participants with HI and 35 control participants without HI (25.5 ± 3.56 years) were recruited for this study. Balance outcomes were assessed by using computerized dynamic posturography and long forceplate (NeuroCom Internationa, Clackmas, OR, 2010). Balance tests included sensory organization test (SOT), motor control test (MCT), adaptation test (AT), and unilateral stance (US). Independent T-tests were used to analyze differences in balance between young adults with and without HI. RESULTS: The study is ongoing and to date 16 participants have completed the study. Significant differences were found in the SOT composite score between those with and without HI (HI: 67± 13.62; Control 79.75± 7.30; p<.05). When the tests required the use of the vestibular system to maintain balance, the results indicate significant impairment for participants with HI. This was evident when balancing on an unstable surface with eyes closed [EC] (HI: 46.96 ± 25.66; Control: 67.62 ± 11.38) as well as balancing on an unstable surface with incorrect visual information (HI: 37.29 ± 26.04; Control: 69.95 ± 15.51). A significant difference was also found in the single leg stance EC condition on both legs. The participants with HI showed significantly higher sway velocity (degree/sec) during EC conditions (LF: 4.92 ± 0.67; RT: 6.79 ± 2.85), which indicates unstable balance compared to controls. No difference was found between the two groups for the MCT and AT. CONCLUSION: The results showed that there are differences between young adults with and without HI. When a test required the use of the vestibular system, the balance of participants with HI was less stable compared to adults without HI.