Shut out the light.

Bright lights in hospital nurseries may contribute to the development of an eye disease in premature babies, according to researchers at George Washington University in Washington, D.C., reporting in the Aug. 15 NEW ENGLAND JOURNAL OF MEDICINE.

Among premature infants less than 2.2 poinds, 19 out of 21 (86 percent) of those exposed to bright light later developed retinopathy -- a degenerative eye disease common in premature infants (SN: 12/1/84, p. 351)--while only 21 out of 39 (54 percent) of those exposed to dimmer light developed retinopathy. Older infants -- more than 2.2 pounds, but still premature -- also developed fewer cases of retinopathy if they were cared for in dimmer light, but the differences were not significant, according to the researchers.

The researchers report that although the typical level of lighting in offices is 40 to 50 footcandles, lighting in intensive care nurseries averaged 90 footcandles in 1982 and can go as high as 190 in some -- not counting additional lighting from sunshine and sunlamps, which may add 300 footcandles.

In the study, bright lights averaged 60 footcandles and the dimmer lights 25 footcandles. The researchers suggest that a cycle of dark/dim or dark/light might be better for infants' eyes than the 24 hours of bright light common in hospital nurseries.