SCHOOL AGE CONSEQUENCES OF <750 GRAM BIRTHWEIGHT

研究人员目前正在跟踪一个58人的区域队列， 出生体重低于750克的儿童从学龄早期到平均 年龄为14岁，以及53名儿童的匹配对照组， 750-1499 g出生体重和62个足月出生对照。他们的研究结果显示， 在小于750克的儿童中，总体和特定发育障碍的发生率 有证据表明，随着时间的推移，后遗症会持续甚至加重。 延续项目的目的是扩大这一样本的后续行动 进入青春期中后期（平均年龄16岁），通过以下方式检查大脑状态： 磁共振成像（MRI），并研究生物学的有效性 和社会-家庭风险来解释结果的可变性。此外 为了跟踪以前测量的结果，研究人员将管理 神经心理学测试敏感的类型的脑损伤持续 低出生体重儿将同时获得MRI，结果 检查与特定大脑结构的形态测量有关。 假设1是小于750 g出生体重的后遗症将变得更多 在青春期中后期出现与低出生率的梯度相一致 由于体重影响，研究人员预计低出生体重 相对于足月出生的对照组， 750 g的那一组。假设2是基于MRI的形态测量将识别 两个低出生体重组的脑结构异常， 足月出生的对照组，在小于750 g的体重中有更严重的异常， 组假设3是生物学和社会家庭风险将占 对于青少年结果的个体差异以及在青少年中观察到的变化， 学龄期。预期特定的结构-功能关系 将大脑形态与记忆、执行功能和 视觉感知技能结果将澄清长期后遗症少 出生体重超过750克，并揭示了两个不利的基础上， 后果和发展保护。

The investigators are currently following a regional cohort of 58 children with less that 750 g birth weight from early school age through a mean age of 14 years, together with matched comparison groups of 53 children with 750-1499 g birth weight and 62 term-born controls. Their findings show higher rates of both global and specific developmental disorders in less that 750 g children, with evidence for continuing and even increasing sequelae over time. The purposes of the continuation project are to extend follow-up of this sample into middle to late adolescence (mean age 16 years), examine brain status via magnetic resonance imaging (MRI), and investigate the validity of biological and social-familial risks in accounting for variability in outcome. In addition to tracking outcomes measured previously, the investigators will administer neuropsychological tests sensitive to the types of brain insults sustained by low birth weight children. MRIs will be obtained concurrently, and outcomes examined in relation to morphometric measures of specific brain structures. Hypothesis 1 is that sequelae of less than 750 g birth weight will become more pronounced in mid to later adolescence. Consistent with a gradient of low birth weight effects, the investigators anticipate sequelae in both low birth weight groups relative to term-born controls, with more marked effects in the less that 750 g group. Hypothesis 2 is that MRI-based morphometry will identify abnormalities in brain structure in both low birth weight groups relative to term-born controls, with more severe abnormalities in the less than 750 g group. Hypothesis 3 is that biological and social-familial risks will account for individual differences in adolescent outcomes and in changes observed over the school-age years. Specific structure-function relationships are anticipated in relating brain morphology to measures of memory, executive function, and visual-perceptual skill. Results will clarify the long-term sequelae of less than 750 g birth weight and shed light on the bases of both adverse consequences and developmental sparing.