Kuo H-K, Yen C-J, Bean J F
Division of Gerontology Research, National Health Research Institutes, National Taiwan University Hospital, Taipei, Taiwan.
J Intern Med. 2005 Oct;258(4):328-35. doi: 10.1111/j.1365-2796.2005.01546.x.
Cardiovascular fitness represents the ability of active skeletal muscle to utilize oxygen during aerobic exercise. Elevated homocysteine, causing tissue injury by such mechanisms as oxidative stress, endothelial damage, and protein homocysteinylation, is associated with increased risk of cardiovascular disease, dementia and osteoporotic fracture. However, the association between elevated homocysteine and cardiovascular fitness has not been reported.
Population-based cross-sectional study.
National Health and Nutrition Examination Survey from 1999 to 2002 in the USA.
A total of 1444 noninstitutionalized adults aged 20--49 years with reliable measures of cardiovascular fitness and non-missing values in homocysteine. Main outcome measures. Cardiovascular fitness, estimated maximal oxygen uptake or VO(2)max (mL kg(-1) min(-1)), was obtained by a submaximal exercise test. Levels of homocysteine were measured by the Abbott homocysteine assay, a fully automated fluorescence polarization immunoassay method and were natural-log-transformed due to right skewness. RESULTS. After adjustment for age, race and body mass index, there was a 0.70 mL kg(-1) min(-1) decrease (P=0.033) in the estimated VO(2)max for each standard deviation (SD) increase in the natural-log-transformed homocysteine level for women. Additional adjustment of hypertension, diabetes, smoking status, alcohol intake, use of lipid-lowering agents, physical activity, self-report health condition, as well as levels of folate, vitamin B(12), creatinine, C-reactive protein, total cholesterol and haemoglobin seemed to influence the association. In the fully adjusted model, we observed a 1.18 mL kg(-1) min(-1) decrease (P=0.003) in the estimated VO(2)max for each SD increase in the natural-log-transformed homocysteine level in women. There was no association between cardiovascular fitness and homocysteine levels in men. CONCLUSION. High homocysteine levels were inversely associated with cardiovascular fitness in women, but not in men. The results suggest that homocysteine levels are important indicators of exercise tolerance amongst women and may be useful in targeting female individuals requiring endurance intervention to prevent loss of cardiovascular fitness and function.
心血管适能代表了活跃骨骼肌在有氧运动期间利用氧气的能力。同型半胱氨酸升高通过氧化应激、内皮损伤和蛋白质同型半胱氨酸化等机制导致组织损伤，与心血管疾病、痴呆和骨质疏松性骨折风险增加相关。然而，同型半胱氨酸升高与心血管适能之间的关联尚未见报道。
基于人群的横断面研究。
1999年至2002年美国国家健康与营养检查调查。
共有1444名年龄在20至49岁的非机构化成年人，其心血管适能测量可靠且同型半胱氨酸值无缺失。主要结局指标。心血管适能通过次极量运动试验获得估计的最大摄氧量或VO₂max（毫升·千克⁻¹·分钟⁻¹）。同型半胱氨酸水平采用雅培同型半胱氨酸检测法测量，这是一种全自动荧光偏振免疫分析方法，由于数据呈右偏态分布，对其进行自然对数转换。结果。在对年龄、种族和体重指数进行调整后，女性自然对数转换后的同型半胱氨酸水平每增加一个标准差（SD），估计的VO₂max下降0.70毫升·千克⁻¹·分钟⁻¹（P = 0.033）。对高血压、糖尿病、吸烟状况、饮酒量、降脂药物使用、体力活动、自我报告的健康状况以及叶酸、维生素B₁₂、肌酐、C反应蛋白、总胆固醇和血红蛋白水平进行进一步调整似乎会影响这种关联。在完全调整模型中，我们观察到女性自然对数转换后的同型半胱氨酸水平每增加一个SD，估计的VO₂max下降1.18毫升·千克⁻¹·分钟⁻¹（P = 0.003）。男性的心血管适能与同型半胱氨酸水平之间无关联。结论。高同型半胱氨酸水平与女性的心血管适能呈负相关，但与男性无关。结果表明，同型半胱氨酸水平是女性运动耐力的重要指标，可能有助于针对需要耐力干预以防止心血管适能和功能丧失的女性个体。
