A QUANTITATIVE REVIEW OF MORTALITY AND DEVELOPMENTAL DISABILITY IN EXTREMELY PREMATURE NEWBORNS

Objectives: To summarize the literature on mortality rates and prevale nces of major neurodevelopmental disabilities and to examine trends of these outcomes over time in extremely premature neonates. Data Source s: MEDLINE was used to search the English literature for studies publi shed since 1970 reporting on both mortality and disability in infants born at or before 26 weeks' gestation (extremely immature [EI] cohort) , with a birth weight of 800 g or less (extremely small [ES] cohort), or subgroups of these. Study Selection: Studies were included in the a nalysis if all of the following were reported: mortality; direct exami nation of 75% or more of the survivors; and the proportion of patients with at least 1 of the following disabilities: cerebral palsy, mental retardation, blindness, and deafness. Studies reporting cohorts inclu ded as a subset of cohorts in another study were excluded. Forty-two s tudies providing mortality and disability data for 20 cohorts of 4116 EI infants and 38 cohorts of 4345 ES infants born after 1972 met the i nclusion criteria. Data Extraction: Data were abstracted from all stud ies that met these criteria by two of us (J.M.L. and D.E.W.), independ ently; the data were then cross-checked to ensure accuracy. Results: S urvival averaged 41% for EI infants and 30% for ES infants, and it inc reased significantly with time. In contrast to mortality, the prevalen ces of major neurodevelopmental disabilities among survivors have not changed over time. The most common major disability was mental retarda tion, found in 14% of EI and ES survivors. Cerebral palsy was found in 12% of EI survivors and 8% of ES survivors, blindness was found in 8% of EI and ES survivors, and deafness was found in 3% of EI and ES sur vivors. Overall, 22% of EI survivors and 24% of ES survivors were clas sified as having at least 1 major disability. Each 100 EI or ES livebi rths yielded 7 children with major disabilities; this prevalence was c orrelated with survival across cohorts. Conclusions: The prevalence of disabilities had not changed among EI or ES survivors with increasing survival. However, increasing survival of these infants has resulted in a steadily increasing prevalence of children with disabilities.