Effect of a light-darkness cycle on preterm infants

The Continuous bright light conditions that premature infants experience while hospitalized in Neonatal Intensive Care Units (NICU) can have harmful effects on their growth and development. 

A recent study evaluated the benefits of a light/darkness cycle (LDC) in weight and early hospital discharge from the NICU. It recruited subjects from three participating institutions in Mexico and included premature infants (n = 294) who were hospitalized in the low-risk and high-risk neonatal units and classified as stable. It randomized the patients to the experimental group (n = 150) and the control group (n = 144).

The experimental group received LDC conditions as follows: light from 07:00 to 19:00 and darkness (25 lx) from 19:00 to 07:00. The control group received normal room light conditions (CBL) 24 h a day. The study looked for weight gain and the effect of reducing the intensity of nocturnal light in the development of premature infants.

• It observed earlier weight gain in infants subjected to the LDC, compared with those randomized to CBL. 
• LDC also showed a significant reduction in the length of hospital stay. 

These results show that premature infants subjected to LDC exhibit improvements in physiological development, favoring earlier weight gain and, consequently, a decrease in hospital stays.

Sci Rep. 2022 Oct 20;12(1):17569. doi: 10.1038/s41598-022-22533-1. PMID: 36266474; PMCID: PMC9584226.