LONDON: Sleeping with the light on might help stave off eye problems and the risk of blindness for hundreds of thousands of people suffering from diabetes, researchers say.

The researchers, from Cardiff University and the University of Wales College of Medicine, said that they hoped they were on the “brink of a breakthrough” in fighting a condition that is the leading cause for people in the UK aged between 16 and 64 to be registered blind.

The scientists warned that more research was necessary before they could think of recommending a “lights on” policy. But they believed they had shown that a shortage of oxygen in the retina in darkness was a large factor in retinopathy, a problem that may be suffered by about a quarter of the 1.4 million known diabetes sufferers in Britain.

The results of an experiment involving seven people with type two diabetes, and eight others without diabetes, were reported in the medical journal, the Lancet.

Neville Drasdo, leader of the research, said good management of diabetes helped slow the progress of retinopathy. The light sensitive cells of the eye — the rod receptors used for night vision — needed more oxygen in darkness than any other cell in the body, he said.

“In diabetes there is a thickening of the walls of the capillaries, so a lack of oxygen is expected during dark adaptation (as the eye accommodates to the dark). This would be expected to occur in the vicinity of the rods, but the retinopathy develops nearer the retina surface. This research proves these layers are also affected by hypoxia during dark adaptation in diabetes.”

Light transmitted even through the closed lids of people sleeping was enough to prevent dark adaptation. —Dawn/The Guardian News Service.