Centre for International Health, University of Bergen, Bergen, Norway.
Am J Clin Nutr. 2013 Feb;97(2):310-7. doi: 10.3945/ajcn.111.032268. Epub 2013 Jan 2.
Micronutrient deficiencies can affect cognitive function. Many young children in low- and middle-income countries have inadequate cobalamin (vitamin B-12) status.
The objective was to measure the association of plasma concentrations of folate, cobalamin, total homocysteine, and methylmalonic acid with cognitive performance at 2 occasions, 4 mo apart, in North Indian children aged 12-18 mo.
Bayley Scales of Infant Development II were used to assess cognition. In multiple regression models adjusted for several potential confounders, we measured the association between biomarkers for folate and cobalamin status and psychomotor or mental development scores on the day of blood sampling and 4 mo thereafter.
Each 2-fold increment in plasma cobalamin concentration was associated with a significant increment in the mental development index score of 1.3 (95% CI: 0.2, 2.4; P = 0.021). Furthermore, each 2-fold increment in homocysteine or methylmalonic acid concentration was associated with a decrement in mental development index score of 2.0 (95% CI: 0.5, 3.4; P = 0.007) or 1.1 (95% CI: 0.3, 1.8; P = 0.004) points, respectively. Plasma folate concentration was significantly and independently associated with mental development index scores only when children with poor cobalamin status were excluded, ie, in those who had cobalamin concentrations below the 25th percentile. None of these markers was associated with psychomotor scores in the multiple regression models.
Cobalamin and folate status showed a statistically significant association with cognitive performance. Given the high prevalence of deficiencies in these nutrients, folate and cobalamin supplementation trials are required to measure any beneficial effect on cognition.
微量营养素缺乏会影响认知功能。许多中低收入国家的幼儿都存在钴胺素（维生素 B-12）摄入不足的情况。
本研究旨在测量印度北部 12-18 月龄儿童血浆叶酸、钴胺素、总同型半胱氨酸和甲基丙二酸浓度与 4 个月内两次认知表现的相关性。
采用贝利婴幼儿发展量表第二版评估认知能力。在调整了几个潜在混杂因素的多元回归模型中，我们测量了血液样本采集日和 4 个月后，生物标志物与叶酸和钴胺素状态和精神运动或智力发育评分之间的关系。
血浆钴胺素浓度每增加 2 倍，精神发育指数评分显著增加 1.3 分（95%CI：0.2，2.4；P = 0.021）。此外，同型半胱氨酸或甲基丙二酸浓度每增加 2 倍，精神发育指数评分分别下降 2.0 分（95%CI：0.5，3.4；P = 0.007）或 1.1 分（95%CI：0.3，1.8；P = 0.004）。只有当排除了钴胺素状态较差的儿童（即，钴胺素浓度低于第 25 百分位数的儿童）时，血浆叶酸浓度才与精神发育指数评分显著相关。在多元回归模型中，这些标志物均与精神运动评分无关。
钴胺素和叶酸状态与认知表现呈显著统计学关联。鉴于这些营养素缺乏的高发率，需要进行叶酸和钴胺素补充试验来衡量其对认知的任何有益影响。
