Hypertension in Africa Research Team, School for Physiology, Nutrition and Consumer Sciences, North-West University, Potchefstroom, South Africa.
Clin Exp Hypertens. 2012;34(5):363-9. doi: 10.3109/10641963.2011.649935. Epub 2012 Jun 11.
Silent myocardial ischemia is a predictor of subclinical atherosclerosis driven by increased cardiovascular risk markers, although still unknown in Africans. The aim of this study was to assess if cardiovascular risk markers will be associated with subclinical atherosclerosis. African men were stratified into (i) 24-hour silent ischemia (SI, n = 38) and (ii) without (nSI, n = 40) groups. Ambulatory blood pressure (BP), SI, 12-lead resting electrocardiogram, ultrasound carotid intima-media thickness (CIMT) measurements, and fasting blood samples were obtained. Above-normal cardiovascular risk markers, that is, glucose level, heart rate, BP, and CIMT, were evident in men with SI. Hypertension prevalence was 89% in the African SI men as opposed to 64% in the nSI men. Regression analyses revealed that only SI events in SI men explained 35% (95% confidence interval [CI]: 0.22;0.52) of the variance in CIMT, while in all African men it explained 29% (95% CI: 0.19;0.39). In conclusion, SI was associated with structural vascular disease in African men. This could imply that SI is not necessarily driven by hypertension in African men but through other possible mechanisms such as increased sympathetic nervous system activity.
无症状性心肌缺血是心血管风险标志物增加导致亚临床动脉粥样硬化的预测因子，尽管在非洲人身上尚未可知。本研究旨在评估心血管风险标志物是否与亚临床动脉粥样硬化相关。非洲男性分为（i）24 小时无症状性缺血（SI，n = 38）和（ii）无 SI（nSI，n = 40）两组。进行了动态血压（BP）、SI、12 导联静息心电图、颈动脉内膜中层厚度（CIMT）超声测量和空腹血样采集。在有 SI 的男性中，存在高于正常的心血管风险标志物，即血糖水平、心率、BP 和 CIMT。在非洲 SI 男性中高血压患病率为 89%，而在 nSI 男性中为 64%。回归分析显示，仅 SI 事件在 SI 男性中可解释 CIMT 变异的 35%（95%可信区间[CI]：0.22；0.52），而在所有非洲男性中可解释 29%（95% CI：0.19；0.39）。总之，SI 与非洲男性的结构性血管疾病相关。这可能意味着 SI 并不一定是由非洲男性的高血压引起的，而是通过其他可能的机制，如增加的交感神经系统活动。
