The hormone, aldosterone, is known to regulate kidney function and also plays a role in controlling levels of two crucial signaling chemicals in the nervous system, potassium and sodium. For nerves to send signals crisply and work properly, potassium and sodium must be in precise proportion, without any disruption in the molecular channels or gates through which they move. Levels of potassium are particularly crucial in the sensitive inner ear, where fluid rich in potassium plays a central role in converting sounds into signals that the nervous system recognizes.

The team of scientists in Rochester, New York, put 47 healthy men and women between the ages of 58 and 84 through a battery of sophisticated hearing tests. Scientists also measured their blood levels of aldosterone, which is known to drop as people age. They found that people with severe hearing loss had on average about half as much aldosterone in their bloodstream as their counterparts with normal hearing. The researchers noted, however, that the levels of aldosterone found in all the participants is considered normal, and that no patients or physicians should consider altering aldosterone levels without more research.

"We found a direct link between blood levels of aldosterone and the ability of people to hear normally as they age”, said Robert D. Frisina, Ph.D., professor of Otolaryngology at the University of Rochester Medical Center. “Depressed hormone levels may hurt hearing both in the inner ear and the part of the brain used for hearing. More research is needed, however, to understand the precise role that aldosterone plays – for instance, whether it's a cause of failed hearing, or whether it's symptomatic."

MEDICA.de; Source: University of Rochester Medical Center