Mearns G J, Koziol-McLain J, Obolonkin V, Rush E C
School of Health Care Practice, Faculty of Health and Environmental Sciences, AUT University, Auckland, New Zealand.
Interdisciplinary Trauma Research Centre, Faculty of Health and Environmental Sciences, AUT University, Auckland, New Zealand.
Eur J Clin Nutr. 2014 Aug;68(8):870-5. doi: 10.1038/ejcn.2014.56. Epub 2014 Apr 16.
BACKGROUND/OBJECTIVES: To examine the effectiveness, acceptability and sustainability of interventions to reduce vitamin B12 (B12) deficiency in South Asian women before conception.
SUBJECTS/METHODS: A 6-month randomised controlled trial conducted in Auckland, New Zealand. Participants (62 South Asian women, 18-50 years old) were stratified by dietary practices, then randomised to three treatment groups: B12 Supplement (oral cyanocobalamin 6 μg/day) (n=21), Placebo (n=21), or B12 Dietary Advice (n=20). Primary outcome measures were changes in B12 biomarkers (serum B12 and holotranscobalamin (holoTC)) at 6 months. Dietary B12 intake was estimated from a B12 food-specific frequency questionnaire (B12FFQ). Intention-to-treat analysis was applied using 'last observation carried forward' method. Changes in B12 biomarkers by treatment were compared using analysis of variance. Pearson's correlations tested relationships between dietary B12 intake and B12 biomarkers.
At baseline, 48% of women tested as insufficient or deficient in serum B12 (<222 pmol/l) and 51% as insufficient or deficient in holoTC (<45 pmol/l). B12 status was moderately correlated with dietary B12 intake (r=0.5, 95% confidence interval (CI) (0.3-0.7)) and 44% of women reported insufficient dietary intake (<2.4 μg/day). B12 Supplement was the only treatment group to record a significant increase in B12 biomarkers over 6 months: serum B12 by 30% (95% CI (11-48%)) and holoTC by 42% (12-72%).
The prevalence of B12 insufficiency among Auckland South Asian women is high and moderately correlated with inadequate intake of foods that contain B12. Cyanocobalamin supplementation (6 μg/day) was associated with improved B12 biomarkers, with a potential to improve preconception B12 status in South Asian women.
背景/目的：研究孕前干预措施对降低南亚女性维生素B12（B12）缺乏症的有效性、可接受性和可持续性。
受试者/方法：在新西兰奥克兰进行的一项为期6个月的随机对照试验。参与者（62名18至50岁的南亚女性）按饮食习惯分层，然后随机分为三个治疗组：B12补充剂组（口服氰钴胺素6μg/天）（n = 21）、安慰剂组（n = 21）或B12饮食建议组（n = 20）。主要结局指标是6个月时B12生物标志物（血清B12和全转钴胺素（holoTC））的变化。通过B12食物特异性频率问卷（B12FFQ）估算膳食B12摄入量。采用“末次观察结转”方法进行意向性分析。使用方差分析比较各治疗组B12生物标志物的变化。Pearson相关性检验膳食B12摄入量与B12生物标志物之间的关系。
基线时，48%的女性血清B12检测为不足或缺乏（<222pmol/l），51%的女性holoTC检测为不足或缺乏（<45pmol/l）。B12状态与膳食B12摄入量中度相关（r = 0.5，95%置信区间（CI）（0.3 - 0.7）），44%的女性报告膳食摄入量不足（<2.4μg/天）。B12补充剂组是唯一在6个月内B12生物标志物显著增加的治疗组：血清B12增加30%（95%CI（11 - 48%）），holoTC增加42%（12 - 72%）。
奥克兰南亚女性中B12不足的患病率较高，且与含B12食物摄入不足中度相关。补充氰钴胺素（6μg/天）与B12生物标志物改善相关，有可能改善南亚女性孕前的B12状态。
