Research is increasingly showing a correlation between diabetes and hearing loss. Several studies point out that the combination of aging, diabetes and central processing or cognitive process decline are correlated with hearing loss. One study conducted at the US Department of Veterans Affairs Medical Center in Portland, Oregon, suggests that diabetics may be more prone than others to hearing loss in middle age. One study showed a 3% greater likelihood of hearing loss in diabetics compared to a similar population of non-diabetics. Hearing loss is only one of a number of complications that can arise from diabetes. For this reason, diabetics undergo routine testing for vision and kidney function, and the researchers suggest that hearing testing should be included in the battery. Renal dysfunction and treatment is often related to hearing as well, because the same foetal tissue that becomes the kidney also becomes the inner ear. The inner ear is a fluid-filled chamber that allows us to hear. When sound moves that fluid, the cells are stimulated and send a nerve signal to the brain. When the signal is weak due to hearing loss, the nerve can have a number of complications. Diabetes may affect either or both the hearing cells or the auditory nerve adversely. Further research is required to determine the exact nature of the adverse effects of diabetes on the physiology of hearing. Studies do show, however, that diabetics under 60 have more hearing loss compared to older diabetics. Therefore, it is suggested that diabetics' auditory system may grow older faster. Furthermore, it appears that past 60 years of age, the aging process may have more effect on hearing loss, especially in diabetics compared to non-diabetics. It is possible that the connection between hearing loss and diabetes is part of a more complex problem altogether. This problem is the general mental decline associated with aging between normal aging and actual dementia. One study has shown that this kind of mental decline is more prevalent among elderly female unmedicated type-2 diabetics. In women aged 70 to 81 years old, those who had had diabetes for 15 years or more were twice as likely to suffer from the problem. The likely cause of all these added challenges associated with diabetes is that the variances in blood sugar levels can damage cellular structure, both sensory and neural. One study concluded that “Overall, the findings revealed an increased incidence of sensorineural hearing loss in diabetics and worse control of diabetes, as measured by increased creatinine, correlates with progressive loss of hearing.” These studies all point out that proper medication for diabetes not only stabilize blood glucose levels but also improves cognitive function and reduces the risk of greater diabetes-related hearing loss. Hearing testing is very important in managing the total impact of diabetes. It is vital that if diagnosed, people with diabetes obtain regular annual hearing tests and use amplification early on when hearing loss is detected. This will result not only in better hearing and improved quality of life relationally and otherwise, but also exercise the auditory system so that deprivation and the reduction of function can be curbed over time. The best solution for diabetes and its associated challenges, however, is avoidance and prevention through proper diet and exercise.
References:
Logroscino, G., Kang, J. H. & Grodstein, F.. Br. Med. J., Department of Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA, and Channing Lab, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, article published online. Venkata Kakarlapudi, MD, Robert Sawyer, MD, Hinrich Staecker, MD, PhD., University of Maryland School of Medicine, Department of Otolaryngology Head & Neck Surgery, Baltimore, MD, American Otological Society presentation. Study by the National Center for Rehabilitative Auditory Research, Dept. of Veterans Affairs, presented at the Assn. for Research in Otolaryngology, Feb. 21-26. "Diabetes and Hearing Loss, Exploring Connections," Hearing Health, Fall 2003.

