BALTIMORE, MD, May 5, 2009 – MedImmune today announced results from a recent study it sponsored, performed by the Kaiser Permanente Division of Research in Oakland, CA, assessing risk factors for respiratory syncytial virus (RSV) infection requiring medical treatment in infants born at 33 weeks gestational age [GA] or later. The analysis suggested that even mild prematurity (e.g., babies born 33-36 weeks GA) is associated with increased risk of medically attended RSV infection, and that this risk is higher among infants exposed to supplemental oxygen or assisted ventilation during the neonatal period. These findings were presented at the 2009 Pediatric Academic Societies (PAS) Annual Meeting in Baltimore, Maryland by Dr. Gabriel J. Escobar.
RSV is a leading cause of viral respiratory infection among preterm infants. Although prematurity is a known risk factor for severe RSV infection, there is little information available on risk factors among moderately (rather than extremely) premature babies.
“The health risks associated with late-preterm birth may be overlooked or misunderstood because these babies often appear as healthy as full-term infants. This study contributes to the growing evidence that, late-preterm infants face greater morbidity and healthcare costs up to at least one year after birth,” noted Parthiv Mahadevia, M.D., senior director, health outcomes and pharmacoeconomics, MedImmune. “In particular, babies born between 33 and 36 weeks GA have under-developed respiratory and immune systems, putting them at heightened risk for severe RSV disease. Doctors, parents, and the health care system should be aware of these babies’ specialized health needs
This study sought to quantify the relationships between neonatal characteristics and the occurrence of RSV infection requiring medical attention in the first year of life.
The study consisted of 117,060 babies born at 33 weeks gestation or later, who were discharged from six hospitals between January 1, 1996, and December 31, 2002. The neonatal characteristics evaluated included GA, infant sex, “small for GA” status, oxygen exposure variables, and hospital discharge during the RSV season.
The authors noted that further research is needed to determine whether strategies to prevent or mitigate RSV infection are needed in late-preterm infants.