Background: Subnormal head circumference (HC) has been associated with poor neurologic and developmental outcomes. Aim: To examine the correlates and consequences of subnormal HC in a cohort of school age, very low bi...Background: Subnormal head circumference (HC) has been associated with poor neurologic and developmental outcomes. Aim: To examine the correlates and consequences of subnormal HC in a cohort of school age, very low birth weight (VLBW, < 1500 g) children. Study design and outcome measures: We examined developmental outcomes at a mean age of 6.8 years in a cohort of 128 VLBW children born from 1982- 1986 and 58 normal birth weight controls. The VLBW cohort included a regional sample of < 750 g birth weight children and matched children with 750- 1499 g birth weight. Outcomes included an IQ equivalent, neuropsychological skills, academic achievement, adaptive behavior, and attention problems. HC was defined along a continuum and as subnormal vs. normal. Linear and logistic regressions were employed to determine the effects of HC on the outcomes after controlling for confounding variables. Results: Thirty one VLBW children (24% ) had subnormal HC vs. none of the controls. The VLBW children with subnormal HC differed significantly from the normal HC group in birth weight (748 g vs. 977 g, p < 0.001), SGA status (52% vs. 27% , p < 0.05), high neonatal risk (57% vs 29% , P < 0.05), and neurosensory impairment (23% vs 8% , P < 0.05). Even after taking these risk factors into account, subnormal HC was associated with poorer IQ equivalent, perceptual motor skills, academic achievement, and adaptive behavior. Results were similar after excluding the children with neurosensory impairment. Conclusions: Subnormal HC is associated with adverse developmental outcomes in VLBW children, independent of other risk factors. Interventions to improve antenatal and postnatal growth may contribute to better school- age outcomes.展开更多
Previous sleep studies of preterm neonates describe the rudimentary expression of sleep state cyclicity after 30 wk postconceptional age (PCA), with stability over multiple cycles only after 36 wk PCA. The research ob...Previous sleep studies of preterm neonates describe the rudimentary expression of sleep state cyclicity after 30 wk postconceptional age (PCA), with stability over multiple cycles only after 36 wk PCA. The research objective for this study was to determine whether sleep state cyclicity was expressed in neonates of 25-30 wk PCA, using two criteria for state identification. Our neonatal sleep consortium includes a total cohort of 359 children who were healthy and medically ill neonates who were recruited from three obstetric-neonatal services and received multiple-hour EEG sleep studies. A subset of the 33 youngest preterm infants were selected to evaluate the first of serial 2-to 3-h EEG-sleep recordings to assess the presence of sleep state cyclicity. One neonatal neurophysiologist visually assigned EEG-sleep characteristics for each record. Rapid eye movement (REM) counts and EEG discontinuity were specifi-cally chosen to assess whether sleep cyclicity was expressed. A combined measure of REM and EEG discontinuity were used in an autocovariance analysis to assess cycling and mean cycle duration. A mean cycle duration of 68 ± 19 min with a range of 37-100 min was determined from the REM-EEG discontinuity state for 24 neonates. The remaining nine infants had absent or poor sleep cyclicity. Sleep state cyclicity is expressed for a majority of neonates between 25 and 30 wk PCA, reflecting an ultradian biologic rhythm during the early perinatal stage of brain development.展开更多
文摘Background: Subnormal head circumference (HC) has been associated with poor neurologic and developmental outcomes. Aim: To examine the correlates and consequences of subnormal HC in a cohort of school age, very low birth weight (VLBW, < 1500 g) children. Study design and outcome measures: We examined developmental outcomes at a mean age of 6.8 years in a cohort of 128 VLBW children born from 1982- 1986 and 58 normal birth weight controls. The VLBW cohort included a regional sample of < 750 g birth weight children and matched children with 750- 1499 g birth weight. Outcomes included an IQ equivalent, neuropsychological skills, academic achievement, adaptive behavior, and attention problems. HC was defined along a continuum and as subnormal vs. normal. Linear and logistic regressions were employed to determine the effects of HC on the outcomes after controlling for confounding variables. Results: Thirty one VLBW children (24% ) had subnormal HC vs. none of the controls. The VLBW children with subnormal HC differed significantly from the normal HC group in birth weight (748 g vs. 977 g, p < 0.001), SGA status (52% vs. 27% , p < 0.05), high neonatal risk (57% vs 29% , P < 0.05), and neurosensory impairment (23% vs 8% , P < 0.05). Even after taking these risk factors into account, subnormal HC was associated with poorer IQ equivalent, perceptual motor skills, academic achievement, and adaptive behavior. Results were similar after excluding the children with neurosensory impairment. Conclusions: Subnormal HC is associated with adverse developmental outcomes in VLBW children, independent of other risk factors. Interventions to improve antenatal and postnatal growth may contribute to better school- age outcomes.
文摘Previous sleep studies of preterm neonates describe the rudimentary expression of sleep state cyclicity after 30 wk postconceptional age (PCA), with stability over multiple cycles only after 36 wk PCA. The research objective for this study was to determine whether sleep state cyclicity was expressed in neonates of 25-30 wk PCA, using two criteria for state identification. Our neonatal sleep consortium includes a total cohort of 359 children who were healthy and medically ill neonates who were recruited from three obstetric-neonatal services and received multiple-hour EEG sleep studies. A subset of the 33 youngest preterm infants were selected to evaluate the first of serial 2-to 3-h EEG-sleep recordings to assess the presence of sleep state cyclicity. One neonatal neurophysiologist visually assigned EEG-sleep characteristics for each record. Rapid eye movement (REM) counts and EEG discontinuity were specifi-cally chosen to assess whether sleep cyclicity was expressed. A combined measure of REM and EEG discontinuity were used in an autocovariance analysis to assess cycling and mean cycle duration. A mean cycle duration of 68 ± 19 min with a range of 37-100 min was determined from the REM-EEG discontinuity state for 24 neonates. The remaining nine infants had absent or poor sleep cyclicity. Sleep state cyclicity is expressed for a majority of neonates between 25 and 30 wk PCA, reflecting an ultradian biologic rhythm during the early perinatal stage of brain development.
