Perinatal and childhood predictors of general cognitive outcome at 28 years in a very-low-birthweight national cohort.

AIM: To determine IQ at 26 to 30 years in very-low-birthweight (VLBW) adults compared with term-born controls; and to examine the stability of IQ in VLBW individuals between 7 to 8 years and 26 to 30 years, identify perinatal and social predictors of IQ, and assess the contribution of brain volume to IQ. METHOD: At 26 to 30 years, 229 VLBW adults (71% survivors of prospectively enrolled national cohort) and 100 term-born controls were tested on the Wechsler Abbreviated Scale of Intelligence. For VLBW, IQ at 7 to 8 years, perinatal and social data were extracted from the data set, and 150 adults underwent volumetric cranial magnetic resonance imaging (MRI). RESULTS: At 26 to 30 years, the mean adjusted difference between VLBW and controls for total IQ was 9.4 (95% CI 6.5-12.4) points. In VLBW individuals the correlation between IQ scores at 7 to 8 years and 26 to 30 years was 0.78. On multiple regression analysis, parental education was the strongest predictor of verbal and total IQ at both ages. Birthweight was a strong predictor of perceptual and total IQ. In VLBW individuals with MRI scans, the addition of brain volume as a variable increased the variance explained for perceptual and total IQ. INTERPRETATION: VLBW adults have mean IQ scores 9 to 11 points below controls. Parental education and birthweight are the strongest predictors of IQ.

The New Zealand 1986 very low birth weight cohort as young adults: mapping the road ahead.

BACKGROUND: Very low birth weight (less than 1500 g) is associated with increased morbidity and costs of health care in childhood. Emerging evidence suggests these infants face a range of health and social problems as young adults. We studied all New Zealand very low birth weight infants born in 1986 (when 58% were exposed to antenatal corticosteroids) in infancy, with later follow-up at 7 to 8 years and 23 to 24 years. We now aim to assess the cohort at 26-28 years compared with controls. METHODS/DESIGN: The case sample will comprise a minimum of 250 members of the 1986 New Zealand national very low birth weight cohort (77% of survivors). Outcomes will be compared with a control group of 100 young adults born at term in 1986. Following written informed consent, participants will travel to Christchurch for 2 days of assessments undertaken by experienced staff. Medical assessments include growth measures, vision, respiratory function, blood pressure and echocardiogram, renal function, dental examination and blood tests. Cognitive and neuropsychological functioning will be assessed with standard tests, and mental health and social functioning by participant interview. A telephone interview will be conducted with a parent or significant other person nominated by the respondent to gain a further perspective on the young person's health and functioning. All those born at less than 28 weeks' gestation, plus a random subset of the cohort to a total of 150 cases and 50 controls, will be offered cranial magnetic-resonance imaging. Statistical analysis will examine comparison with controls and long-term trajectories for the very low birth weight cohort. DISCUSSION: The research will provide crucial New Zealand data on the young adult outcomes for very low birth weight infants and address gaps in the international literature, particularly regarding cardiovascular, respiratory, visual and neurocognitive outcomes. These data will inform future neonatal care, provide evidence-based guidelines for care of preterm graduates transitioning to adult care, and help shape health education and social policies for this high risk group. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12612000995875 . Registered 1 October 2012.

Identifying very preterm children at educational risk using a school readiness framework.

OBJECTIVES: Children born very preterm (VPT) are at high risk of educational delay, yet few guidelines exist for the early identification of those at greatest risk. Using a school readiness framework, this study examined relations between preschool neurodevelopmental functioning and educational outcomes to age 9 years. METHODS: The sample consisted of a regional cohort of 110 VPT (≤ 32 weeks' gestation) and 113 full-term children born during 1998-2000. At corrected age 4 years, children completed a multidisciplinary assessment of their health/motor development, socioemotional adjustment, core learning skills, language, and general cognition. At ages 6 and 9, children's literacy and numeracy skills were assessed using the Woodcock-Johnson III Tests of Achievement. RESULTS: Across all readiness domains, VPT children were at high risk of delay/impairment (odds ratios 2.5-3.5). Multiple problems were also more common (47% vs 16%). At follow-up, almost two-thirds of VPT children were subject to significant educational delay in either literacy, numeracy or both compared with 29% to 31% of full-term children (odds ratios 3.4-4.4). The number of readiness domains affected at age 4 strongly predicted later educational risk, especially when multiple problems were present. Receiver operating characteristic analysis confirmed ≥ 2 readiness problems as the optimal threshold for identifying VPT children at educational risk. CONCLUSIONS: School readiness offers a promising framework for the early identification of VPT children at high educational risk. Findings support the utility of ≥ 2 affected readiness domains as an effective criterion for referral for educational surveillance and/or additional support during the transition to school.