Epidemiological Cardiology Research Center, Department of Epidemiology and Prevention, Division of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
J Am Coll Cardiol. 2012 Apr 17;59(16):1460-7. doi: 10.1016/j.jacc.2012.01.025.
The purpose of this study was to examine the association between prolongation of QT interval corrected for heart rate (QTc) with incident stroke.
Unlike cardiovascular morbidity and mortality, little is known about the relationship between QTc and risk of stroke.
A total of 27,411 participants age 45 years and older without previous stroke from the REGARDS (REasons for Geographic and Racial Differences in Stroke) study were included in this analysis. QTc was calculated using Framingham formula (QTc(Fram)). Stroke cases were identified and adjudicated during up to 8.2 years of follow-up (median, 5.1 years).
The risk of incident stroke in study participants with prolonged QTc(Fram) was almost 3 times the risk in those with normal QTc(Fram) (hazard ratio [HR] [95% confidence interval (CI)]: 2.88 [2.12 to 3.92], p < 0.0001). After adjustment for demographics (age, race, and sex), traditional stroke risk factors (antihypertensive medication use, systolic blood pressure, current smoking, diabetes, left ventricular hypertrophy, atrial fibrillation, and previous cardiovascular disease), warfarin use, aspirin use, QRS duration and use of QTc-prolonging drugs, the risk of stroke remained significantly high (HR [95% CI]: 1.67 [1.16 to 2.41], p = 0.0061) and was consistent across several subgroups of REGARDS study participants. Similar results were obtained when the risk of stroke was estimated per 1-SD increase in QTc(Fram), (HR [95% CI]: 1.12 [1.03 to 1.21], p = 0.0053 in multivariable-adjusted model) and when other QTc correction formulas including those of Hodge, Bazett, and Fridericia were used.
QTc prolongation is associated with a significantly increased risk of incident stroke independent of traditional stroke risk factors. Examining the risk of stroke associated with QTc-prolonging drugs may be warranted.
本研究旨在探讨校正心率后的 QT 间期（QTc）延长与卒中事件的关系。
与心血管发病率和死亡率不同，关于 QTc 与卒中风险的关系知之甚少。
本研究共纳入 27411 名年龄在 45 岁及以上且无既往卒中的 REGARDS（地理和种族差异导致的卒中原因）研究参与者，分析采用 Framingham 公式（QTc（Fram））计算 QTc。在长达 8.2 年的随访期间（中位随访时间为 5.1 年），确定并判定卒中病例。
校正 QTc（Fram）正常的研究参与者，发生卒中的风险是校正 QTc（Fram）延长患者的近 3 倍（风险比[HR] [95%置信区间（CI）]：2.88 [2.12 至 3.92]，p<0.0001）。在调整了人口统计学因素（年龄、种族和性别）、传统卒中危险因素（降压药物使用、收缩压、当前吸烟、糖尿病、左心室肥厚、心房颤动和既往心血管疾病）、华法林使用、阿司匹林使用、QRS 间期和使用致 QTc 延长药物后，卒中风险仍然显著较高（HR [95%CI]：1.67 [1.16 至 2.41]，p=0.0061），并且在 REGARDS 研究参与者的几个亚组中结果一致。当按 QTc（Fram）每增加 1 个标准差估计卒中风险时（HR [95%CI]：1.12 [1.03 至 1.21]，p=0.0053 于多变量调整模型），以及当使用包括 Hodge、Bazett 和 Fridericia 在内的其他 QTc 校正公式时，也得到了类似的结果。
校正心率后的 QTc 延长与独立于传统卒中危险因素的卒中事件风险显著增加相关。检查与 QTc 延长药物相关的卒中风险可能是合理的。
