Hearing loss may be an under-recognised complication of diabetes, according to US researchers, who found hearing loss to be roughly twice as common in people who have the disease as those who do not.
Writing on Monday in the Annals of Internal Medicine, the researchers said hearing tests given to a nationally representative sample of U.S. adults revealed higher rates of hearing loss among adult diabetics.
The researchers analysed data from 5,140 adults aged 20 to 69 who were given hearing tests.
Low- or mid-frequency hearing impairment of mild or greater severity was detected in 21 per cent of the 399 people with diabetes and 9 per cent of the 4,741 who did not have it.
High-frequency hearing impairment of mild or greater severity was present in 54 per cent of those with diabetes compared to 32 per cent of those without it, the study found.
The differences in hearing between diabetics and non-diabetics occurred among both men and women and in all racial and ethnic groups, education levels and income levels, the researchers said.
Diabetes may cause hearing loss by damaging the nerves and blood vessels of the inner ear, according to the researchers.
The researchers noted that the link between diabetes and hearing loss has been debated since at least the 1960s.
"Hearing loss may be an under-recognized complication of diabetes. As diabetes becomes more common, the disease may become a more significant contributor to hearing loss," researcher Catherine Cowie of the National Institute of Diabetes and Digestive and Kidney Diseases, part of the U.S. National Institutes of Health, said in a statement.
The researchers said the study identifies an important public health problem that can be addressed. "With the high prevalence of hearing impairment among diabetic patients, screening for this condition may be justified," they wrote.
Diabetes is a disease marked by high levels of sugar in the blood. In the two types of diabetes -- one that typically begins in childhood and the other more common form that is closely tied to obesity and a sedentary lifestyle -- the excess sugar in the blood damages organs including the eyes, kidneys and heart.
Recent research has identified other complications of diabetes. Last month, the US Centers for Disease Control and Prevention said people with diabetes are twice as likely to have arthritis.
Diabetes is becoming more common in the United States and other countries as obesity rates increase.