MEDICATIONS: CLINICAL CONDITIONS CAN PREDICT IMPAIRMENT AND DEATH FOR EXTREMELY LOW BIRTH WEIGHT INFANTS

March 4 2003 — Three clinical complications that occur in extremely low birth weight (ELBW) infants strongly predict the risk of later death or neurological impairment, according to an article in the March 5 issue of The Journal of the American Medical Association.

According to background information in the article, parents of very pre-term infants fear the development of bronchopulmonary dysplasia (BPD, a form of longer lasting lung disease), brain injury (such as bleeding in the brain), and severe retinopathy of prematurity (ROP, abnormal development of the retina) because these conditions are risk factors for later impairment in childhood. However, it is uncertain to what degree each impairment can predict later childhood neurosensory problems.

Barbara Schmidt, M.D., M.Sc., of McMaster University, Ontario, and colleagues examined the individual and combined prognostic impact of BPD, brain injury and severe ROP on the 18-month outcome of ELBW infants who survived to a post-menstrual age of 36 weeks (about 9 months after the mother's last menstrual period prior to pregnancy). The researchers studied 910 infants born at an average of 26 weeks gestational age and with birth weights of 500 to 999 grams (17.6 to 35.2 ounces) who were admitted to one of 32 neonatal intensive care units in Canada, the United States, Australia, New Zealand, and Hong Kong between 1996 and 1998, and who survived to a postmenstrual age of 36 weeks.

The researchers found that each of the neonatal morbidities was independently and similarly linked to poor 18-month outcomes. Poor outcomes included death or survival to 18 months, with one or more of the following conditions: cerebral palsy, cognitive delay, severe hearing loss and bilateral blindness. Children were 2.4 times as likely to have poor outcomes at 18 months if they had BPD, 3.7 times as likely if they had a brain injury and 3.1 times as likely if they had severe ROP. In children who were free of BPD, brain injury, and severe ROP, the rate of poor long-term outcomes was 18 percent. Corresponding rates with any one, any two or all three morbidities were 42 percent, 62 percent and 88 percent, respectively.

"... Clinicians need valid evidence that allows them to estimate the risk of impairment with reasonable accuracy," the authors write. "We report that, in ELBW infants who survive to a postmenstrual age of 36 weeks, the prediction of late death or of survival with neurosensory impairment is greatly improved by a simple count of three common neonatal morbidities: BPD, brain injury, and severe ROP. This new finding should improve our ability to counsel parents and to anticipate special needs."