Filtered sunlight treats hyperbilirubinemia in resource-poor Nigeria

Last Updated: 2015-09-16

By Gene Emery

NEW YORK (Reuters Health) - When standard phototherapy is unavailable to treat newborns with hyperbilirubinemia, filtered sunlight can offer a safe and inexpensive substitute, according to a new study of hundreds of Nigerian infants.

The finding, reported online September 16 in The New England Journal of Medicine, comes 15 months after the researchers reported in the journal Pediatrics that the technique worked in 92% of cases. But that test didn't have a control group that compared filtered sunlight to conventional phototherapy. Roughly twice as many children were involved in the new test.

Filtered sunlight "would be applicable to any place that does not have consistent electric service, which is much of Nigeria and many other low-to-middle income countries," chief author Dr. Tina Slusher of the Center for Global Pediatrics at the University of Minnesota told Reuters Health in a telephone interview.

She and her colleagues from Nigeria and the U.S. discovered that filtered sunlight worked on 93% of the days that could be evaluated versus 90% of the days conventional phototherapy was given.

The finding "is definitely useful, especially for Third World low-income countries," said Dr. Pradeep Mally, chief of the division of neonatology at the NYU Langone Medical Center, who was not connected with the research.

"We always knew sunlight was effective," he told Reuters Health by phone. "This is one of the few studies to actually document it," and it reinforces advice often given to mothers in developed countries to take their newborn for brief walks in the sun the first two or three days after birth.

"One of the commonest causes of readmission to the hospital is jaundice," Dr. Mally said.

More than 75% of the 481,000 newborns diagnosed with severe hyperbilirubinemia each year are born in low- and middle-income countries. About 114,000 die and 63,000 end up with moderate to severe disabilities such as deafness, language processing problems, choreoathetoid cerebral palsy and developmental delays.

It is a particularly common problem in Nigeria and other parts of the world because an enzyme deficiency that makes people resistant to malaria increases the risk of neonatal jaundice, said Dr. Slusher.

The new noninferiority study was done at a large inner-city hospital in Lagos on 447 infants with mild-to-moderate hyperbilirubinemia. Half the babies were treated with conventional phototherapy units for at least five hours daily. The rest were put under canopies topped with special films that screened out the hazardous ultraviolet light and some heat radiation, but let varying amounts of therapeutic blue light through, depending on whether the skies were clear or overcast.

If bilirubin levels remained too high, as they did in 13% of the babies, the children were also given nighttime phototherapy.

Babies with levels greater than 15 mg/dL were not included in the study.

The technique is now being tested in newborns with moderate-to-severe jaundice, and "based on data from older studies looking at conventional phototherapy, we believe it will work even better in them," Dr. Slusher said. "If that happens, it will really take off and be upscalable to every place that needs it."

In the new study of infants in the mild-to-moderate category, most babies only needed five or six hours per day of sunlight exposure for one to two days, the researchers said.

Bilirubin levels fell significantly faster in filtered sunlight than with conventional phototherapy.

The researchers used wet towels under and around the infant to prevent overheating if the sunlight made things too hot. If the temperatures got too high, the baby was moved to the shade.

The wet towels were used because the babies were overheating in 24% of the periodic temperature checks on babies treated with sunlight and 7% of the checks for babies getting conventional treatment.

Cases of hypothermia were managed by briefly wrapping the child in cloth and, if needed, placing the baby on the mother's chest to pick up her warmth.

Under the rules of the study, infants who consistently had hyperthermia or hypothermia, serious sunburn or dehydration during the trial were supposed to be removed from the study, but that did not become a problem for any of the babies.

"The current advantages of filtered sunlight include its availability in remote locations, the provision of treatment at the safest and most efficacious wavelength, and, when a large canopy is used, the increased opportunity for maternal-infant bonding, for the provision of skin-to-skin care, and for the feeding of infants when they are hungry," the researchers wrote.

As for the cost, the most expensive canopy for six to eight mothers and their babies was $120, "as compared with commercial phototherapy devices that cost between $2,000 and $3,500 per unit," they said. "However, open-air canopies require warm, sunny climates, which may not be available year-round in some low-to-middle-income countries, and protection from storms and heavy rains."

Dr. Slusher, who has been working in Nigeria for over 26 years, said that not only does inconsistent or nonexistent electrical service make conventional phototherapy impractical in countries like Nigeria, many medical facilities can't afford the bulbs for the units, nor can they afford to buy the equipment to test existing bulbs to see if they are still working effectively.

Thus, "several studies that had been done in Nigeria have told us much of the phototherapy in Nigeria is ineffective," she said.

Dr. Mally said he suspects the problem is also common in the U.S., estimating that, at any given time, perhaps one third of the phototherapy units in hospitals aren't giving off enough light because they aren't checked weekly, unnecessarily prolonging the child's time in the hospital.

SOURCE: http://bit.ly/1L6VLLJ

N Engl J Med 2015.