To examine the neurosensory and cognitive status of extremely low-birth-weight (ELBW; <1000 g) children born from January 1, 1992, through December 31, 1995, and to identify the significant predictors of outcome.
An inception cohort of ELBW infants admitted to the neonatal intensive care unit (NICU) and observed to 20 months' corrected age.
A tertiary level urban NICU and follow-up clinic at a university hospital.
Of 333 ELBW infants without major congenital malformations admitted to the NICU, 241 (72%) survived to 20 months' corrected age. We studied 221 children (92%) at a mean of 20 months' corrected age. The mean birth weight was 813 g; mean gestational age, 26.4 weeks.
Main Outcome Measures
Assessments of cognitive and neurosensory development.
Major neurosensory abnormality was present in 54 children (24%), including 33 (15%) with cerebral palsy, 20 (9%) with deafness, and 2 (1%) with blindness. The mean (± SD) Bayley Mental Developmental Index (MDI) score was 74.7 ± 17. Ninety-two children (42%) had a subnormal MDI score (<70). Neurodevelopmental impairment (neurosensory abnormality and/or MDI score <70) was present in 105 children (48%). Multiple stepwise logistic regression analysis that considered sex, social risk, birth weight, and neonatal risk factors revealed significant predictors of a subnormal MDI score to be male sex (odds ratio [OR], 2.73; 95% confidence interval [CI], 1.52-4.92), social risk (OR, 1.48; 95% CI, 1.09-2.00), and chronic lung disease (OR, 2.18; 95% CI, 1.20-3.94). Predictors of neurologic abnormality were a severely abnormal finding on cerebral ultrasound (OR, 8.09; 95% CI, 3.69-17.71) and chronic lung disease (OR, 2.46; 95% CI, 1.12-5.40); predictors of deafness were male sex (OR, 2.79; 95% CI, 1.02-7.62), sepsis (OR, 3.15; 95% CI, 1.05-9.48), and jaundice (maximal bilirubin level, >171 µmol/L [>10 mg/dL]) (OR, 4.80; 95% CI, 1.46-15.73).
There is an urgent need for research into the etiology and prevention of neonatal morbidity.