A study just released in the October 1, 2010 issue of the American Journal of Kidney Diseases has demonstrated an interesting correlation between kidney disease and hearing loss, particularly in people aged fifty and older.
This Reuters article, Moderate kidney disease linked to hearing loss, describes the findings:
In the study, of adults aged 50 years and older, 54 percent of people with moderate kidney disease had some extent of hearing loss, while 30 percent of those with the disease suffered severe hearing loss.
One reason this is significant is that for the general population in the same age range, the rate of hearing loss is only 18 percent. But even recognizing some kind of connection between this disease and the loss of one’s hearing, the next question is whether this link is causal, or merely coincidental.
According to the Australian authors of the study, the connection is not, in fact, a causal one. Kidney disease doesn’t cause the hearing loss, or vice versa. So what explains the correlation between them? Dr. David Harris, of the University of Sydney, is one of the study authors. He explains that there are “structural and functional similarities” between tissues in the kidney and the inner ear. So the same physical pressures, toxins, and risk factors that affect kidneys may also affect the inner ear.
Does this connection actually matter, then, if one problem doesn’t cause the other? Yes it does. If you experience some degree of hearing loss, you may be prompted to have your doctor check your kidney function, and detect potential disease much earlier. And if you have the disease, it may be useful to have your ears checked, to take much earlier steps to preserve your hearing.
Because of how the bodily systems interact, problems in one area can provide hints that there may be problems in others.
(Other source: Chronic Kidney Disease Might Affect Hearing, Bloomberg Businessweek, October 6, 2010)