Simon J A, Hudes E S, Tice J A
General Internal Medicine Section, Veterans Affairs Medical Center, San Francisco, California 94121, USA.
J Am Coll Nutr. 2001 Jun;20(3):255-63. doi: 10.1080/07315724.2001.10719040.
To examine the relation between serum ascorbic acid (SAA), a marker of dietary intake (including supplements), and cause-specific mortality.
We analyzed data from a probability sample of 8,453 Americans age > or = 30 years at baseline enrolled in the Second National Health and Nutrition Examination Survey (NHANES II), who were followed for mortality endpoints. We calculated relative hazard ratios as measures of disease association comparing the mortality rates in three biologically relevant SAA categories.
Participants with normal to high SAA levels had a marginally significant 21% to 25% decreased risk of fatal cardiovascular disease (CVD) (p for trend = 0.09) and a 25% to 29% decreased risk of all-cause mortality (p for trend <0.001) compared to participants with low levels. Because we determined that gender modified the association between SAA levels and cancer death, we analyzed these associations stratified by gender. Among men, normal to high SAA levels were associated with an approximately 30% decreased risk of cancer deaths, whereas such SAA levels were associated with an approximately two-fold increased risk of cancer deaths among women. This association among women persisted even after adjustment for baseline prevalent cancer and exclusion for early cancer death or exclusion for prevalent cancer.
Low SAA levels were marginally associated with an increased risk of fatal CVD and significantly associated with an increased risk for all-cause mortality. Low SAA levels were also a risk factor for cancer death in men, but unexpectedly were associated with a decreased risk of cancer death in women. If the association between low SAA levels and all-cause mortality is causal, increasing the consumption of ascorbic acid, and thereby SAA levels, could decrease the risk of death among Americans with low ascorbic acid intakes.
研究血清抗坏血酸（SAA，饮食摄入包括补充剂的一个标志物）与特定病因死亡率之间的关系。
我们分析了来自第二次全国健康与营养检查调查（NHANES II）中8453名基线年龄≥30岁的美国概率样本的数据，这些人被随访至死亡终点。我们计算相对风险比作为疾病关联的度量，比较三个生物学相关的SAA类别中的死亡率。
与SAA水平低的参与者相比，SAA水平正常至高的参与者致命心血管疾病（CVD）风险略微显著降低21%至25%（趋势p值 = 0.09），全因死亡率风险降低25%至29%（趋势p值<0.001）。由于我们确定性别改变了SAA水平与癌症死亡之间的关联，我们按性别分层分析了这些关联。在男性中，SAA水平正常至高与癌症死亡风险降低约30%相关，而在女性中，此类SAA水平与癌症死亡风险增加约两倍相关。即使在调整基线时的癌症患病率以及排除早期癌症死亡或排除现患癌症后，女性中的这种关联仍然存在。
低SAA水平与致命CVD风险略有增加相关，与全因死亡率风险显著增加相关。低SAA水平也是男性癌症死亡的一个风险因素，但出乎意料的是，在女性中与癌症死亡风险降低相关。如果低SAA水平与全因死亡率之间的关联是因果关系，增加抗坏血酸的摄入量从而提高SAA水平，可能会降低抗坏血酸摄入量低的美国人的死亡风险。
