Diabetes has already been tied to an increased risk of kidney and cardiovascular troubles, nerve damage and vision loss. Now, a japanese study finds diabetics to be more than twice as likely as those without the disease to have hearing impairment.

A review of past research on the issue was published in the journal of clinical endocrinology and metabolism. Scientists found that younger diabetics were at even higher risk than older adults, though they could not explain why, but it's not the first time researchers have found a link between diabetes and hearing loss.

In 2008, researchers from the u-s national institutes of health saw similar patterns in a sample of more than eleven thousand people, with people with diabetes twice as likely to have hearing loss as those without.

It's thought that high blood sugar levels brought on by diabetes may lead to hearing loss by damaging blood vessels in the ears.