Tong Shilu, Baghurst Peter, McMichael Anthony
School of Public Health, Queensland University of Technology, Kelvin Grove, Australia.
J Paediatr Child Health. 2006 Mar;42(3):98-103. doi: 10.1111/j.1440-1754.2006.00805.x.
Low birthweight has been reported to be associated with lower IQ at school age. Further, some evidence suggests that the association extends across the range of normal birthweights. This study assessed the relationship of birthweight to cognitive development in the Port Pirie birth cohort.
Of 723 singleton live births recruited into a prospective birth cohort study, 601, 548, 494 and 375 children were followed at ages 2, 4, 7 and 11-13 years, respectively. The children's developmental status was assessed using the Bayley Scales of Infant Development at age 2 years, the McCarthy Scales of Children's Abilities at age 4 years, and the revised Wechsler Intelligence Scale for Children at ages 7 and 11-13 years. The association between birthweight and cognitive function was assessed with multiple linear regression, adjusting for a wide range of possible confounders.
The mean birthweight was 3386 g (SD: 517). There was a statistically significant association between birthweight and cognitive performance at age 2 years (adjusted deficit: 0.97 points per 100 g lighter; 95% CI: 0.4-1.5), but the magnitude of this association gradually decreased and became statistically non-significant at later childhood.
The relationship between birthweight and cognitive development becomes progressively attenuated at increasing age. At older ages, socioenvironmental factors appear to play an increasingly important part in children's cognitive development.
据报道，低出生体重与学龄期较低的智商有关。此外，一些证据表明这种关联在正常出生体重范围内也存在。本研究评估了皮里港出生队列中出生体重与认知发展的关系。
在一项前瞻性出生队列研究招募的723例单胎活产儿中，分别在2岁、4岁、7岁和11 - 13岁时对601名、548名、494名和375名儿童进行了随访。使用贝利婴儿发展量表在2岁时评估儿童的发育状况，使用麦卡锡儿童能力量表在4岁时评估，使用修订的韦氏儿童智力量表在7岁和11 - 13岁时评估。通过多元线性回归评估出生体重与认知功能之间的关联，并对多种可能的混杂因素进行校正。
平均出生体重为3386克（标准差：517）。出生体重与2岁时的认知表现之间存在统计学显著关联（校正后每轻100克 deficit为0.97分；95%置信区间：0.4 - 1.5），但这种关联的强度在儿童后期逐渐降低并变得无统计学意义。
出生体重与认知发展之间的关系随着年龄增长逐渐减弱。在较大年龄时，社会环境因素在儿童认知发展中似乎起着越来越重要的作用。
