Rosenthal Jorge, Largaespada Natalia, Bailey Lynn B, Cannon Michael, Alverson C J, Ortiz Dayrin, Kauwell Gail Pa, Sniezek Joe, Figueroa Ramon, Daly Robyn, Allen Peter
National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA;
Belize Ministry of Health, Belmopan, Belize.
J Nutr. 2017 Jun;147(6):1183-1193. doi: 10.3945/jn.116.242628. Epub 2017 Apr 12.
Folate deficiency, vitamin B-12 deficiency, and anemia can have adverse effects on birth outcomes. Also, low vitamin B-12 reduces the formation of metabolically active folate. We sought to establish the baseline prevalence of and factors associated with folate deficiency and insufficiency, vitamin B-12 deficiency, and anemia among women of childbearing age (WCBA) in Belize. In 2011, a national probability-based survey was completed among Belizean nonpregnant WCBA aged 15-49 y. Blood samples for determination of hemoglobin, folate (RBC and serum), and vitamin B-12 (plasma) and sociodemographic and health information were collected from 937 women. RBC and serum folate concentrations were measured by microbiologic assay (MBA). Folate status was defined based on both the WHO-recommended radioproteinbinding assay and the assay adjusted for the MBA. The national prevalence estimates for folate deficiency in WCBA, based on serum and RBC folate concentrations by using the assay-matched cutoffs, were 11.0% (95% CI: 8.6%, 14.0%) and 35.1% (95% CI: 31.3%, 39.2%), respectively. By using the assay-matched compared with the WHO-recommended cutoffs, a substantially higher prevalence of folate deficiency was observed based on serum (6.9% absolute difference) and RBC folate (28.9% absolute difference) concentrations. The prevalence for RBC folate insufficiency was 48.9% (95% CI: 44.8%, 53.1%). Prevalence estimates for vitamin B-12 deficiency and marginal deficiency and anemia were 17.2% (95% CI: 14.2%, 20.6%), 33.2% (95% CI: 29.6%, 37.1%), and 22.7% (95% CI: 19.5%, 26.2%), respectively. The adjusted geometric means of the RBC folate concentration increased significantly (-trend < 0.001) in WCBA who had normal vitamin B-12 status relative to WCBA who were vitamin B-12 deficient. In Belize, the prevalence of folate and vitamin B-12 deficiencies continues to be a public health concern among WCBA. Furthermore, low folate status co-occurred with low vitamin B-12 status, underlining the importance of providing adequate vitamin B-12 and folic acid intake through approaches such as mandatory food fortification.
叶酸缺乏、维生素B-12缺乏和贫血会对出生结局产生不利影响。此外，低水平的维生素B-12会减少代谢活性叶酸的形成。我们试图确定伯利兹育龄妇女中叶酸缺乏和不足、维生素B-12缺乏及贫血的基线患病率及其相关因素。2011年，在伯利兹15至49岁未怀孕的育龄妇女中完成了一项基于全国概率的调查。从937名妇女中采集了用于测定血红蛋白、叶酸（红细胞和血清）、维生素B-12（血浆）的血样以及社会人口统计学和健康信息。红细胞和血清叶酸浓度通过微生物学测定法（MBA）进行测量。叶酸状态根据世界卫生组织推荐的放射蛋白结合测定法以及针对MBA调整后的测定法来定义。根据使用与测定法匹配的临界值的血清和红细胞叶酸浓度，伯利兹育龄妇女叶酸缺乏的全国患病率估计分别为11.0%（95%置信区间：8.6%，14.0%）和35.1%（95%置信区间：31.3%，39.2%）。与世界卫生组织推荐的临界值相比，基于血清（绝对差异6.9%）和红细胞叶酸（绝对差异28.9%）浓度观察到叶酸缺乏的患病率显著更高。红细胞叶酸不足的患病率为48.9%（95%置信区间：44.8%，53.1%）。维生素B-12缺乏、边缘性缺乏和贫血的患病率估计分别为17.2%（95%置信区间：14.2%，20.6%）、33.2%（95%置信区间：29.6%，37.1%）和22.7%（95%置信区间：19.5%，26.2%）。相对于维生素B-12缺乏的育龄妇女，维生素B-12状态正常的育龄妇女红细胞叶酸浓度的校正几何平均数显著升高（-趋势<0.001）。在伯利兹，叶酸和维生素B-12缺乏的患病率仍然是育龄妇女中的一个公共卫生问题。此外，低叶酸状态与低维生素B-12状态同时存在，这突出了通过强制食品强化等方法提供充足维生素B-12和叶酸摄入量的重要性。
