The Southern Illinois University School of Medicine in Springfield in the United States has been awarded a $1.2 million, three-year grant from the U.S. Department of Defense to work with drug therapies to prevent and treat noise-induced hearing loss, particularly in military settings.
More than one-third of servicemen and women have some degree of hearing loss when they retire from the military. In addition to disadvantages in the field caused by hearing loss, it can also lead to post-traumatic stress disorder, anxiety and depression.
The work involves the use of an antioxidant called D-methionine, a component of fermented protein that is found in yoghurt and cheese. The antioxidant, in concentrated doses, has been found to improve some forms of hearing loss and even prevent hearing loss before the exposure to noise. The researchers have already found that the drug can be given up to seven hours after the noise is experienced and still be effective.
"We've been able to show in animal studies that if we give it before and after noise exposure, we can get pretty much full protection from noise-induced hearing loss," the leader of the research team, audiologist Kathleen Campbell, said.
"It doesn't mean it's going to work for long-standing hearing loss, but it does mean that in the early stages, you could intervene and keep it from becoming permanent," she said.
The research will move into determining if even more time can elapse between the drug is given and it still having an effect.
Human clinical trials with the U.S. Army are in the early planning stages, Campbell said.
Father with hearing loss
Campbell's father lost some hearing while serving on a Navy carrier during World War II. Other members of her family are disabled Army veterans.
"My heart is in getting something to prevent noise-induced hearing loss in our troops," she said. "It makes them more vulnerable in the battlefield if they can't detect the enemy."