Stabler S P, Allen R H, Fried L P, Pahor M, Kittner S J, Penninx B W, Guralnik J M
Division of Hematology, Department of Medicine, University of Colorado Health Sciences Center, Denver, CO, USA.
Am J Clin Nutr. 1999 Nov;70(5):911-9. doi: 10.1093/ajcn/70.5.911.
Many previous investigations of cobalamin and folate status were performed in white populations.
Our objective was to determine whether there are racial differences in the prevalence of cobalamin and folate deficiency.
The study was a cross-sectional comparison of baseline serum cobalamin, folate, methylmalonic acid (MMA), total homocysteine (tHcy), and creatinine concentrations, complete blood count, and vitamin supplementation in 550 white and 212 African American subjects from a cohort of physically disabled older women.
The mean (+/-SD) serum MMA concentration was significantly higher in whites than in African Americans: 284 +/- 229 compared with 218 +/- 158 nmol/L (P = 0.0001). tHcy concentration was higher in African Americans than in whites: 12.4 +/- 7.0 compared with 10.9 +/- 4.6 micromol/L (P = 0.001). Serum cobalamin was lower in whites (P = 0.0002). Cobalamin deficiency (serum cobalamin <258 pmol/L and MMA >271 nmol/L) was more frequent in the white women (19% compared with 8%; P < 0.0003). Folate deficiency (serum folate <11.4 nmol/L, tHcy >13.9 micromol/L, and MMA <271 nmol/L) was more prevalent in African Americans than in whites (5% compared with 2%; P = 0.01). Multivitamin use was associated with lower tHcy but not with MMA concentrations. Regression models showed that age >85 y, African American race, serum creatinine >90 micromol/L, and high MMA concentration were all significantly correlated with higher tHcy. Creatinine > 90 micromol/L, white race, and folate concentration were positively associated with MMA concentration.
Cobalamin deficiency with elevated serum MMA concentration is more prevalent in elderly white than in African American women and elevated serum tHcy and folate deficiency are more prevalent in elderly African American than in white women.
以往许多关于钴胺素和叶酸状况的调查是在白人人群中进行的。
我们的目的是确定钴胺素和叶酸缺乏的患病率是否存在种族差异。
该研究是一项横断面比较，比较了来自一组身体残疾老年女性队列中的550名白人及212名非裔美国受试者的基线血清钴胺素、叶酸、甲基丙二酸（MMA）、总同型半胱氨酸（tHcy）和肌酐浓度、全血细胞计数以及维生素补充情况。
白人的平均（±标准差）血清MMA浓度显著高于非裔美国人：分别为284±229与218±158 nmol/L（P = 0.0001）。非裔美国人的tHcy浓度高于白人：分别为12.4±7.0与10.9±4.6 μmol/L（P = 0.001）。白人的血清钴胺素较低（P = 0.0002）。钴胺素缺乏（血清钴胺素<258 pmol/L且MMA >271 nmol/L）在白人女性中更为常见（19%与8%；P < 0.0003）。叶酸缺乏（血清叶酸<11.4 nmol/L、tHcy >13.9 μmol/L且MMA <271 nmol/L）在非裔美国人中比在白人中更普遍（5%与2%；P = 0.01）。服用多种维生素与较低的tHcy相关，但与MMA浓度无关。回归模型显示，年龄>85岁、非裔美国人种族、血清肌酐>90 μmol/L以及高MMA浓度均与较高的tHcy显著相关。肌酐>90 μmol/L、白人种族和叶酸浓度与MMA浓度呈正相关。
血清MMA浓度升高的钴胺素缺乏在老年白人女性中比在非裔美国女性中更普遍，而血清tHcy升高和叶酸缺乏在老年非裔美国女性中比在白人女性中更普遍。
