Robinson K, Arheart K, Refsum H, Brattström L, Boers G, Ueland P, Rubba P, Palma-Reis R, Meleady R, Daly L, Witteman J, Graham I
Department of Cardiology, The Cleveland Clinic Foundation, Ohio 44195, USA.
Circulation. 1998 Feb 10;97(5):437-43. doi: 10.1161/01.cir.97.5.437.
A high plasma homocysteine concentration is a risk factor for atherosclerosis, and circulating concentrations of homocysteine are related to levels of folate and vitamin B6. This study was performed to explore the interrelationships between homocysteine, B vitamins, and vascular diseases and to evaluate the role of these vitamins as risk factors for atherosclerosis.
In a multicenter case-control study in Europe, 750 patients with documented vascular disease and 800 control subjects frequency-matched for age and sex were compared. Plasma levels of total homocysteine (before and after methionine loading) were determined, as were those of red cell folate, vitamin B12, and vitamin B6.
In a conditional logistic regression model, homocysteine concentrations greater than the 80th percentile for control subjects either fasting (12.1 micromol/L) or after a methionine load (38.0 micromol/L) were associated with an elevated risk of vascular disease independent of all traditional risk factors. In addition, concentrations of red cell folate below the lowest 10th percentile (<513 nmol/L) and concentrations of vitamin B6 below the lowest 20th percentile (<23.3 nmol/L) for control subjects were also associated with increased risk. This risk was independent of conventional risk factors and for folate was explained in part by increased homocysteine levels. In contrast, the relationship between vitamin B6 and atherosclerosis was independent of homocysteine levels both before and after methionine loading.
Lower levels of folate and vitamin B6 confer an increased risk of atherosclerosis. Clinical trials are now required to evaluate the effect of treatment with these vitamins in the primary and secondary prevention of vascular diseases.
血浆同型半胱氨酸浓度升高是动脉粥样硬化的一个危险因素，同型半胱氨酸的循环浓度与叶酸和维生素B6水平相关。本研究旨在探讨同型半胱氨酸、B族维生素与血管疾病之间的相互关系，并评估这些维生素作为动脉粥样硬化危险因素的作用。
在欧洲的一项多中心病例对照研究中，对750例有血管疾病记录的患者和800例年龄和性别频率匹配的对照者进行了比较。测定了血浆总同型半胱氨酸水平（蛋氨酸负荷前后）以及红细胞叶酸、维生素B12和维生素B6水平。
在条件逻辑回归模型中，对照者空腹时（12.1微摩尔/升）或蛋氨酸负荷后（38.0微摩尔/升）同型半胱氨酸浓度高于第80百分位数与血管疾病风险升高相关，且独立于所有传统危险因素。此外，对照者红细胞叶酸浓度低于最低的第10百分位数（<513纳摩尔/升）和维生素B6浓度低于最低的第20百分位数（<23.3纳摩尔/升）也与风险增加相关。这种风险独立于传统危险因素，对于叶酸来说，部分原因是同型半胱氨酸水平升高。相比之下，维生素B6与动脉粥样硬化之间的关系在蛋氨酸负荷前后均独立于同型半胱氨酸水平。
较低的叶酸和维生素B6水平会增加动脉粥样硬化的风险。现在需要进行临床试验来评估用这些维生素进行治疗在血管疾病一级和二级预防中的效果。
