Older adults with poorer low-contrast vision also have an increased risk of hearing impairment, according to research in the January issue of Ophthalmic & Physiological Optics.

In seeking to determine which vision variables are associated with moderate bilateral hearing loss in an elderly population, a team of scientists at the Smith-Kettlewell Eye Research Institute in San Francisco recently took a look at a cohort of older adults enrolled in a longitudinal study of vision and function in Marin County, California.

They found that among 446 older adults (mean age of 79.9 years), three measures of low-contrast visual acuity were significantly associated with moderate bilateral hearing loss in analyses controlling for age and comorbid conditions: overall low-contrast acuity, low-contrast acuity at low luminance and low contrast and acuity in glare.

“If vision and hearing impairments were independent … we would expect dual sensory loss in 0.7% of people,” the authors wrote. “In fact, the prevalence of dual sensory loss was over four times higher (3.1%), indicating that the two kinds of impairment are associated.”

While poorer vision for low-contrast targets was associated with an increased risk of hearing impairment in older adults, normal or high-contrast acuity measures were not significantly associated with hearing loss.

“The findings have significance for clinicians, both audiologists and eye care practitioners, in that finding a deficit in one domain (e.g., vision) indicates an increased likelihood of deficits in the other domain (e.g., hearing),” the authors concluded.

They also suggest that, “audiologists consider including a brief test of low-contrast vision, such as low-contrast acuity. Likewise, eye care practitioners should consider performing a screening test of hearing on their patients.”

Losing both vision and hearing is debilitating in other ways, the authors add. Dual sensory loss can have greater effects on depression, cognitive function and quality of life compared with sensory hearing or vision loss alone.

Schneck ME, Lott LA, Haegerstrom-Portnoy G, Brabyn JA. Association between hearing and vision impairments in older adults. Ophthalmic Physiol Opt. 2012 Jan;32(1):45-52.