This week, NEJM published a study with major implications for patients and providers in low-resource settings. Slusher and her colleagues designed a trial in Nigeria to evaluate the safety and efficacy of sunlight canopies to treat neonatal jaundice. If neonatal bilirubin levels get too high, babies can develop kernicterus and have serious long-term neurologic impairment. In developed countries, neonates with elevated bilirubin levels are treated with blue light from an electronic source. This is usually achieved by placing the baby in a phototherapy bed or using “bili blankets.” Bili blankets are similar to an electric blanket used to wrap up a (nearly) naked baby while emitting blue light. These methods are effective, but they are expensive and require maintenance and a consistent source of electricity.
So, what about babies born in Africa and other low-resource settings? Is there a low-resource option? We have long known that sunlight includes blue light. Babies have been placed in direct sunlight to treat neonatal jaundice for centuries. But, if the levels are really high, you probably aren’t going to get enough benefit before overheating the little one. In comes the sunlight canopy. Sunlight canopies were designed to filter out most of the rays (UVA, UVB, UVC, IR, etc.), but allow the therapeutic blue light to pass through. This decreases substantially the risks of overheating and sunburn. But, there has been no large-scale trial to show if natural sunlight through a filtering canopy is safe and efficacious. That is what Slusher and colleagues managed to accomplish.
They randomized 447 newborns with elevated bilirubin levels to receive phototherapy (like we do in the US) or filtered sunlight under the canopies. The study was designed as a non-inferiority trial to establish whether the sunlight/canopy strategy is a safe and effective alternative to the more expensive phototherapy. 224 infants were assigned to receive filtered sunlight under the canopy. 223 infants were assigned to receive phototherapy. Both groups showed a therapeutic decrease in bilirubin level after starting with an average of 6mg/dL. There were no adverse events requiring study withdrawal in either group. Infants under the canopy were more likely to develop mild hyperthermia, but never to an unsafe temperature. The authors concluded that filtered sunlight canopies are not inferior and that filtered sunlight phototherapy offers a safe and efficacious option in settings where phototherapy is not available. This study is exciting, because it arms providers in low-resource, tropical settings with an affordable and sustainable option. Filtered sunlight therapy using these canopies will likely become the standard of care in low-resource settings, at least those in the parts of the world where sunlight is abundant.