TUESDAY, Sept. 29 (HealthDay News) -- Wealthy people are twice as likely to suffer retinal detachment as poorer people, according to Scottish researchers who said they couldn't identify the reason for the disparity.

Retinal detachment -- the separation of the retina from its connection at the back of the eye -- usually occurs as a result of a tear in the retina. If patients don't receive immediate treatment, retinal detachment can lead to permanent vision loss.

The new study included 572 patients diagnosed with primary retinal detachment in Scotland over a one-year period between 2007 and 2008. The rate of retinal detachment was 15.4 per 100,000 population among the most affluent patients, compared with 13.6 per 100,000 for the second-most affluent patients, 9.3 per 100,000 for the third-most affluent patients, and 6.9 per 100,000 among the least affluent patients.

This was a surprising finding that's never been reported before, said Dr. David Yorston of Gartnavel General Hospital in Glasgow, and colleagues.

"We have not found any satisfactory explanation for the greater incidence of [retinal detachment] in less deprived patients. It is possible that a combination of small differences in known risk factors, such as myopia [short-sightedness] and previous cataract surgery account for the difference," they wrote. "However, we cannot exclude the possibility that affluence is associated with some other, hitherto, unknown risk factor."

The study appears online Sept. 29 in the British Journal of Ophthalmology.

More information

The U.S. National Eye Institute has more about retinal detachment.