The short version
- A Moorfields and UCL team compared speech-in-noise hearing tests with eye scans in 32,613 adults from the UK Biobank.
- Poorer hearing went with slightly thinner inner and middle layers of the retina, even after adjusting for age, diabetes, smoking and other factors.
- The differences were very small and measured at one point in time, so the study cannot say which comes first or why.
A team led by Laura Meliante at Moorfields Eye Hospital and the UCL Institute of Ophthalmology has linked hearing to the structure of the eye. Writing in Investigative Ophthalmology & Visual Science on November 4, they compared two measurements in 32,613 UK Biobank adults, average age about 57: a test of how well each person picked out speech against background noise, and an optical scan of the retina. According to a summary in Hearing Health & Technology Matters, 5,475 participants, about 17%, had impaired results on the hearing test.
People with poorer hearing had slightly thinner inner and middle retinal layers, the ones that hold the nerve cells that process the image, even after adjustment for age, sex, diabetes, smoking, alcohol, education, deprivation and air pollution. Each 1-dB worse hearing threshold went with about 0.20 micrometers less total thickness at the center of the retina. The outer layers, including the light-sensing cells, showed no link.
The authors’ summary describes the differences as very small. The study took one snapshot, used a speech-in-noise test instead of a full hearing exam, and did not look at dementia. It suggests the ear and the eye may age along a shared path, and it does not yet show how.
