Wannamethee S Goya, Lowe Gordon D O, Rumley Ann, Bruckdorfer K Richard, Whincup Peter H
Department of Primary Care and Population Sciences, Royal Free and University College Medical School, London, United Kingdom.
Am J Clin Nutr. 2006 Mar;83(3):567-74; quiz 726-7. doi: 10.1093/ajcn.83.3.567.
It has been suggested that a high dietary intake and high circulating concentrations of vitamin C may protect against ischemic heart disease.
The objective was to examine the associations between dietary and plasma vitamin C concentrations, fruit and vegetable intakes, and markers of inflammation and hemostasis associated with cardiovascular disease in older men free of cardiovascular disease.
This cross-sectional study examined 3258 men aged 60-79 y with no physician diagnosis of myocardial infarction, stroke, or diabetes and who were drawn from general practices in 24 British towns. Fruit and vegetable intakes and dietary vitamin C were assessed by using a food-frequency questionnaire.
Plasma vitamin C, fruit intake, and dietary vitamin C intake were significantly and inversely associated with mean concentrations of C-reactive protein, an acute phase reactant, and tissue plasminogen activator (t-PA) antigen, a marker of endothelial dysfunction, even after adjustment for confounders. Vegetable intake was correlated significantly (inversely) only with t-PA. For plasma vitamin C (highest versus lowest quartile), the adjusted odds of elevated C-reactive protein and t-PA (highest tertile versus lowest tertile) were 0.56 (95% CI: 0.44, 0.71) and 0.79 (0.62, 1.00); for fruit intake, the corresponding odds ratios were 0.76 (0.60, 0.95) and 0.76 (0.61, 0.95). Plasma (but not dietary) vitamin C also showed inverse associations with both fibrinogen concentrations and blood viscosity. No associations were seen with von Willebrand factor or factor VIII.
The findings suggest that vitamin C has antiinflammatory effects and is associated with lower endothelial dysfunction in men with no history of cardiovascular disease or diabetes.
有人提出，高膳食摄入量和高循环浓度的维生素C可能预防缺血性心脏病。
目的是研究无心血管疾病的老年男性的膳食和血浆维生素C浓度、水果和蔬菜摄入量与心血管疾病相关的炎症和止血标志物之间的关联。
这项横断面研究调查了3258名年龄在60 - 79岁之间、未被医生诊断为心肌梗死、中风或糖尿病的男性，他们来自英国24个城镇的普通诊所。使用食物频率问卷评估水果和蔬菜摄入量以及膳食维生素C。
即使在调整混杂因素后，血浆维生素C、水果摄入量和膳食维生素C摄入量与急性期反应物C反应蛋白的平均浓度以及内皮功能障碍标志物组织纤溶酶原激活物（t-PA）抗原均呈显著负相关。蔬菜摄入量仅与t-PA显著（负）相关。对于血浆维生素C（最高四分位数与最低四分位数相比），C反应蛋白升高和t-PA（最高三分位数与最低三分位数相比）的校正比值分别为0.56（95%CI：0.44，0.71）和0.79（0.62，1.00）；对于水果摄入量，相应的比值比分别为0.76（0.60，0.95）和0.76（0.61，0.95）。血浆（而非膳食）维生素C还与纤维蛋白原浓度和血液粘度呈负相关。未发现与血管性血友病因子或因子VIII有关联。
研究结果表明，维生素C具有抗炎作用，并且与无心血管疾病或糖尿病病史的男性较低的内皮功能障碍有关。
