Institute of Clinical Medicine, Children's Hospital, Helsinki University Central Hospital, Helsinki, Finland.
Pediatrics. 2010 Jan;125(1):e74-82. doi: 10.1542/peds.2009-1297. Epub 2009 Dec 14.
Children with very low birth weight (VLBW; <1500 g) perform worse on cognitive tests than do children who are born at term. Whether this difference persists into adulthood has been little studied. We assessed core neurocognitive abilities (processing speed, working memory, attention, and learning capacity) in young adults with VLBW and in term-born control subjects.
In conjunction with the Helsinki Study of Very Low Birth Weight Adults, 147 VLBW and 171 control subjects who were aged 18 to 27 years and did not have neurosensory impairments performed a computerized test battery (CogState Ltd, Melbourne, Australia). T tests and linear regression models were used. Cohen's d was used to express effect size (ES).
VLBW adults had slower reaction times than did control subjects on all 5 tasks: simple reaction time (mean difference: 4.0% [95% confidence interval (CI): 1.1%-7.0%]; ES: 0.30), choice reaction time (mean difference: 3.2% [95% CI: 0.3%-6.2%]; ES: 0.24), working memory (mean difference: 8.4% [95% CI: 3.7%-13.4%]; ES: 0.40), divided attention (mean difference: 7.2% [95% CI: 2.7%-11.9%]; ES: 0.36), and associated learning reaction time (mean difference: 6.4% [95% CI: 1.3%-11.9%]; ES: 0.28). In addition, VLBW adults showed impaired learning abilities on the associated learning task (percentage of correct responses: 85.7 vs 80.2; P < .001; ES: 0.64). The results were little affected by adjustment for confounders.
Nonimpaired VLBW individuals exhibited slower psychomotor speed and lower accuracy on the associated learning task. These results indicate that very preterm birth, even when obvious neurosensory deficits are absent, may have long-term consequences on core neurocognitive abilities.
极低出生体重儿（VLBW；<1500 克）在认知测试中的表现不如足月出生的儿童。这种差异是否会持续到成年期，研究甚少。我们评估了 VLBW 年轻成人和足月出生的对照组的核心神经认知能力（处理速度、工作记忆、注意力和学习能力）。
结合赫尔辛基极低出生体重成人研究，147 名 VLBW 和 171 名对照组受试者年龄在 18 至 27 岁之间，无神经感觉障碍，进行了计算机测试组合（CogState Ltd，墨尔本，澳大利亚）。使用 t 检验和线性回归模型。使用 Cohen's d 表示效应大小（ES）。
VLBW 成人在所有 5 项任务中的反应时间均慢于对照组：简单反应时间（平均差异：4.0%[95%置信区间（CI）：1.1%-7.0%]；ES：0.30），选择反应时间（平均差异：3.2%[95% CI：0.3%-6.2%]；ES：0.24），工作记忆（平均差异：8.4%[95% CI：3.7%-13.4%]；ES：0.40），分配注意力（平均差异：7.2%[95% CI：2.7%-11.9%]；ES：0.36）和关联学习反应时间（平均差异：6.4%[95% CI：1.3%-11.9%]；ES：0.28）。此外，VLBW 成人在关联学习任务中的学习能力受损（正确反应百分比：85.7 对 80.2；P<.001；ES：0.64）。结果几乎不受混杂因素调整的影响。
非受损的 VLBW 个体在运动速度和关联学习任务的准确性方面表现较慢。这些结果表明，即使没有明显的神经感觉缺陷，极早产也可能对核心神经认知能力产生长期影响。
