Ribas-Fitó Núria, Júlvez Jordi, Torrent Maties, Grimalt Joan O, Sunyer Jordi
Centre de Recerca en Epidemiologia Ambiental, Institut Municipal Investigació Mèdica, Barcelona, Spain.
Am J Epidemiol. 2007 Nov 15;166(10):1198-202. doi: 10.1093/aje/kwm207. Epub 2007 Sep 22.
The authors previously reported that intrauterine exposure to background concentrations of p,p'-dichlorodiphenyltrichloroethane (DDT) reduces cognitive performance among preschoolers. Breastfeeding has been associated with both increased exposure to certain pollutants during infancy and better performance on cognitive tests. Thus, the authors examined the role of breastfeeding in cognitive function among preschoolers, taking prenatal DDT exposure into account. Two birth cohorts in Spain (Ribera d'Ebre and Menorca) were recruited between 1997 and 1999 (n = 391). Infants were assessed at age 4 years using the McCarthy Scales of Children's Abilities. Levels of organochlorine compounds were measured in umbilical cord serum. Information on type and duration of breastfeeding was obtained by questionnaire when the children were 1 year of age. Children who were breastfed for more than 20 weeks had better cognitive performance regardless of their in utero exposure to DDT. A linear dose response between breastfeeding and cognition was observed in all DDT groups (for children highly exposed to DDT, adjusted beta = 0.30 (standard error, 0.12) per week breastfed). Despite the possibility of harm from environmental contaminants in breast milk, breastfeeding for long periods should still be recommended as the best infant feeding method.
作者之前报道，子宫内暴露于背景浓度的对，对'-二氯二苯三氯乙烷（滴滴涕）会降低学龄前儿童的认知能力。母乳喂养既与婴儿期接触某些污染物增加有关，也与认知测试表现更好有关。因此，作者在考虑产前滴滴涕暴露的情况下，研究了母乳喂养在学龄前儿童认知功能中的作用。1997年至1999年间，在西班牙招募了两个出生队列（埃布罗河沿岸和梅诺卡岛）（n = 391）。使用麦卡锡儿童能力量表在4岁时对婴儿进行评估。测量脐带血清中的有机氯化合物水平。当儿童1岁时，通过问卷调查获得母乳喂养的类型和持续时间信息。无论子宫内是否接触滴滴涕，母乳喂养超过20周的儿童认知表现更好。在所有滴滴涕组中均观察到母乳喂养与认知之间存在线性剂量反应（对于高度接触滴滴涕的儿童，每母乳喂养一周，调整后的β = 0.30（标准误差，0.12））。尽管母乳中的环境污染物可能有害，但仍应推荐长时间母乳喂养作为最佳的婴儿喂养方式。
