Measuring functional outcomes after prematurity: developmental impact of very low birth weight and extremely low birth weight status on childhood disability

Our purpose was to describe functional outcomes in essential activities in preschool, school-age, and adolescent children who were born very (<32 weeks gestation) and extremely (<28 weeks gestation) prematurely. Very low birth weight (VLBW; 1000-1499 g), or extremely low birth weight (ELBW;<1000 g) populations are the focus of our analysis. We describe models of disablement and enablement for specifying the complexity of childhood outcomes using a framework of pathophysiology, impairment, functional limitation and functional strengths, disability in social roles and social participation, societal limitations and environmental facilitators. Representative early childhood, preschool, school-age, and adolescent studies were examined in terms of describing children's functional strengths and challenges after VLBW and ELBW survival. In early childhood, disability was assessed by diagnosing neurosensory impairments and delays on developmental testing. Instruments for measuring functional status in essential activities of self-care, mobility, communication and learning are described. Rates of neurosensory disability in the first three years among recent ELBW survivors ranged from 9-26% for cerebral palsy, 1-15% for blindness, 0-9% for deafness, and 6-42% for evolving cognitive disability (MDI <70). Rates of preschool functional limitation were 5-27% motor, 5-30% self-care, and 5-22% communicative. Rates of school-age functional educational disabilities exceeded 50%. Rates of adolescent activity limitation were 13-32% and vocational limitations were 27-71%. By examining the functional strengths and challenges of children with major neurodevelopmental impairments after very or extremely preterm birth, we can examine causal pathways that lessen the risk of severe functional disability. Among children with mild to moderate disability, we can enhance functional outcomes, optimize community participation, and provide quality family supports. In order to assess the changing outcomes of this vulnerable population of survivors, combinations of clinical and survey based methodologies are required.