Regional Centre for Child and Youth Mental Health and Child Welfare West, NORCE Norwegian Research Centre, Bergen, Norway.
Centre for Health Research and Development, Society for Applied Studies, New Delhi, India;
Pediatrics. 2020 Mar;145(3). doi: 10.1542/peds.2019-2316. Epub 2020 Feb 4.
Vitamin B and folate are important for normal brain development. Our objective for this study was to measure the effects of 6-month supplementation of vitamin B and/or folic acid in early childhood on cognition when the children were 6 to 9 years old.
The study is a follow-up of a factorial randomized, double-blind, placebo-controlled trial in 1000 North Indian children. Children 6 to 30 months of age were randomly assigned to receive a placebo or 1.8 µg of vitamin B, 150 mg of folic acid, or both daily for 6 months. After 6 years, we re-enrolled 791 of these children for cognitive assessments. We compared the scores of the main outcomes (the Wechsler Intelligence Scale for Children, Fourth Edition [India], the Crichton Verbal Scale, and subtests of the NEPSY-II) between the study groups. We also measured the associations between markers of the B vitamins (plasma cobalamin, folate, and total homocysteine concentrations) in early childhood and the cognitive outcomes.
There were no differences between the intervention groups and the placebo group on the cognitive outcomes. Plasma cobalamin, folate, and total homocysteine concentrations in early childhood were associated with the cognitive outcomes at follow-up in the unadjusted models. These associations disappeared in models adjusted for relevant confounders.
Our findings, from both an observational and a randomized design suggest that vitamin B and folate in children 6 to 36 months have limited public health relevance for long-term cognition.
维生素 B 和叶酸对大脑正常发育很重要。本研究旨在测量儿童 6 至 9 岁时补充 6 个月维生素 B 和/或叶酸对认知的影响。
该研究是对 1000 名印度北部儿童进行的一项两因素随机、双盲、安慰剂对照试验的随访。6 至 30 个月大的儿童被随机分配接受安慰剂或每天 1.8μg 维生素 B、150mg 叶酸或两者联合治疗 6 个月。6 年后，我们重新招募了其中的 791 名儿童进行认知评估。我们比较了研究组之间的主要结局（Wechsler 儿童智力量表第四版[印度]、Crichton 言语量表和 NESPY-II 的子测验）得分。我们还测量了儿童早期 B 族维生素标志物（血浆钴胺素、叶酸和总同型半胱氨酸浓度）与认知结局之间的关系。
在认知结局方面，干预组与安慰剂组之间没有差异。儿童早期的血浆钴胺素、叶酸和总同型半胱氨酸浓度与未调整模型中随访时的认知结局相关。这些关联在调整了相关混杂因素的模型中消失了。
我们的观察性和随机设计研究结果表明，6 至 36 个月儿童的维生素 B 和叶酸对长期认知的公共卫生相关性有限。
