Lewis Joshua R, Lim Wai H, Wong Germaine, Abbs Samuel, Zhu Kun, Lim Ee M, Thompson Peter L, Prince Richard L
Sir Charles Gairdner Hospital Unit, University of Western Australia School of Medicine and Pharmacology, Perth, Australia
Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Perth, Australia.
J Am Heart Assoc. 2017 Jul 30;6(8):e004174. doi: 10.1161/JAHA.116.004174.
Elderly women are at high risk of coronary heart disease (CHD) and heart failure. High-sensitivity assays allow detection of cardiac troponin I (hsTnI) well below diagnostic cutoffs for acute coronary syndrome. We investigated the association between these levels with future cardiac events in community-based ambulant white women aged over 70 years initially recruited for a 5-year randomized, controlled trial of calcium supplements.
This was a prospective study of 1081 elderly women without clinical CHD at baseline (1998) or hsTnI above the diagnostic cutoffs for acute coronary syndrome with 14.5-year follow-up hospitalization and mortality (events). Two hundred forty-three (22%) women had CHD events, 163 (15%) myocardial infarction or CHD death (hard CHD), and 109 (10%) heart failure. In 99.6% of available serum samples, hsTnI was above the level of detection (median, 4.5 ng/L; interquartile range, 3.6-5.8). After adjusting for Framingham risk factors, each SD natural log-transformed hsTnI increase was associated with an increased hazard for CHD (hazard ratio, 1.34; 95% CI, 1.18-1.53; <0.001) hard CHD (hazard ratio, 1.51; 95% CI, 1.29-1.76; <0.001), and heart failure (hazard ratio, 1.65; 95% CI, 1.36-1.99; <0.001). Step-wise increases in relative hazards were observed with increasing quartiles of hsTnI ( for trend, <0.001), whereas the addition of hsTnI to conventional risk factors modestly improved discrimination indices: Harrell's c-statistic, net reclassification, and integrated discrimination (<0.05).
Cardiac troponin I is independently associated with future cardiac events in elderly women without apparent clinical manifestations. The addition of cardiac troponin I to conventional risk factors may modestly improve risk prediction in this setting.
老年女性患冠心病（CHD）和心力衰竭的风险较高。高灵敏度检测方法能够检测到远低于急性冠脉综合征诊断临界值的心肌肌钙蛋白I（hsTnI）。我们对最初入选一项为期5年的钙剂补充剂随机对照试验的70岁以上社区流动白人女性进行研究，以探讨这些水平与未来心脏事件之间的关联。
这是一项对1081名基线时（1998年）无临床冠心病或hsTnI高于急性冠脉综合征诊断临界值的老年女性进行的前瞻性研究，随访14.5年观察住院和死亡情况（事件）。243名（22%）女性发生冠心病事件，163名（15%）发生心肌梗死或冠心病死亡（严重冠心病），109名（10%）发生心力衰竭。在99.6%的可用血清样本中，hsTnI高于检测水平（中位数为4.5 ng/L；四分位间距为3.6 - 5.8）。在校正弗雷明汉风险因素后，hsTnI每增加1个标准差的自然对数转换值与冠心病风险增加相关（风险比为1.34；95%置信区间为1.18 - 1.53；P<0.001），严重冠心病（风险比为1.51；95%置信区间为1.29 - 1.76；P<0.001），以及心力衰竭（风险比为1.65；95%置信区间为1.36 - 1.99；P<0.001）。随着hsTnI四分位数的增加，相对风险呈逐步上升趋势（趋势P<0.001），而将hsTnI添加到传统风险因素中可适度改善判别指数：Harrell's c统计量、净重新分类和综合判别（P<0.05）。
心肌肌钙蛋白I与无明显临床表现的老年女性未来心脏事件独立相关。在这种情况下，将心肌肌钙蛋白I添加到传统风险因素中可能会适度改善风险预测。
