The findings, published in the journal Current Diabetes Reports, are based on a review of studies of possible linkages between Type-2 diabetes and hearing impairment.
“An association between diabetes and hearing impairment in human subjects has been shown in many, but not all, studies. Direct comparison of these studies is complicated due to a lack of consistency in defining hearing impairment and other factors,” said one of the researchers Elizabeth Helzner, assistant professor at SUNY Downstate Medical Centre in New York.
“However, the association between diabetes and hearing impairment tends to be stronger in studies that included younger participants, perhaps because in older samples, other causes of age-related hearing impairment may mask the contribution of diabetes to the impairment,” Helzner noted.
“This factor in itself lends weight to the notion that Type-2 diabetes can damage hearing,” Helzner explained.
The researchers, however, added that well-designed longitudinal studies are necessary in order to explore whether patients with diabetes are at increased risk of early-onset hearing impairment, and whether the progression of hearing impairment varies based on diabetes status, as well as disease management factors, after taking other known contributors to hearing sensitivity into account.
Hearing impairment has been associated with social isolation and depression, cognitive decline and incident dementia, a higher propensity for falls and hospitalisations, and increased mortality.