SCHOOL AGE CONSEQUENCES OF <750 GRAM BIRTHWEIGHT

调查人员目前正在跟踪调查58人的地区队列 出生体重低于750克的儿童，从早期学龄到平均体重 年龄14岁，与53名匹配的对照组儿童一起 750-1499克出生体重和62名足月出生对照。他们的调查结果显示 低于750g的全球和特定发育障碍的比率 儿童，有证据表明随着时间的推移，后遗症会持续甚至增加。 延续项目的目的是扩大本样本的后续行动。 进入青春期中后期(平均年龄16岁)，通过 磁共振成像(MRI)，并调查生物学的有效性 以及在考虑结果的可变性方面的社会-家庭风险。此外 为了跟踪之前测量的结果，调查人员将对 对大脑遭受的侮辱类型敏感的神经心理测试 低出生体重儿。核磁共振成像将同时获得，结果是 与特定大脑结构的形态测量相关的检查。 假设1出生体重低于750克的后遗症会变得更多 在青春期中后期明显。与低出生人口的梯度一致 体重效应，研究人员预计这两种低出生体重都会有后遗症 相对于足月出生的对照组，影响更明显的是 750克的那一组。假设2是基于核磁共振成像的形态测量将识别 两组低出生体重儿的脑结构异常 足月出生对照，750g以下异常较严重 一群人。假设3是生物和社会-家庭风险将解释 青春期结果的个体差异和观察到的变化 学龄期。预计会出现特定的结构-功能关系 在将大脑形态与记忆、执行功能和 视觉感知技能。结果将澄清Less的长期后遗症 超过750克的出生体重，并揭示了两者的不利基础 后果和发育节制。

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.