Department of Cardiology, Texas Heart Institute, Houston, Texas, USA.
Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
JACC Heart Fail. 2024 Apr;12(4):757-767. doi: 10.1016/j.jchf.2023.06.009. Epub 2023 Aug 9.
Implantable cardioverter-defibrillator (ICD) therapy is recommended to reduce mortality risk in patients with heart failure with reduced ejection fraction (HFrEF). Frailty is common among patients with HFrEF and is associated with increased mortality risk. Whether the therapeutic efficacy of ICD is consistent among frail and nonfrail patients with HFrEF remains unclear.
The aim of this study was to evaluate the effect modification of baseline frailty burden on ICD efficacy for primary prevention among participants of the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial).
Participants in SCD-HeFT with HFrEF randomized to ICD vs placebo were included. Baseline frailty was estimated using the Rockwood Frailty Index (FI), and participants were stratified into high (FI > median) vs low (FI ≤ median) frailty burden groups. Multivariable Cox models with multiplicative interaction terms (frailty × treatment arm) were constructed to evaluate whether baseline frailty status modified the treatment effect of ICD for all-cause mortality.
The study included 1,676 participants (mean age: 59 ± 12 years, 23% women) with a median FI of 0.30 (IQR: 0.23-0.37) in the low frailty group and 0.54 (IQR: 0.47-0.60) in the high frailty group. In adjusted Cox models, baseline frailty status significantly modified the treatment effect of ICD therapy (P = 0.047). In separate stratified analysis by frailty status, ICD therapy was associated with a lower risk of all-cause mortality among participants with low frailty burden (HR: 0.56; 95% CI: 0.40-0.78) but not among those with high frailty burden (HR: 0.86; 95% CI: 0.68-1.09).
Baseline frailty modified the efficacy of ICD therapy with a significant mortality benefit observed among participants with HFrEF and a low frailty burden but not among those with a high frailty burden.
植入式心脏复律除颤器（ICD）治疗被推荐用于降低射血分数降低的心力衰竭（HFrEF）患者的死亡率风险。虚弱是 HFrEF 患者中常见的现象，与死亡率风险增加相关。在 HFrEF 虚弱和非虚弱患者中，ICD 的治疗效果是否一致尚不清楚。
本研究旨在评估基线虚弱负担对 SCD-HeFT（心力衰竭猝死试验）中 HFrEF 患者一级预防中 ICD 疗效的影响修饰作用。
纳入 SCD-HeFT 中 HFrEF 患者随机分为 ICD 与安慰剂组。使用 Rockwood 虚弱指数（FI）评估基线虚弱情况，将患者分为高（FI>中位数）和低（FI≤中位数）虚弱负担组。构建多变量 Cox 模型，使用乘法交互项（虚弱×治疗臂）评估基线虚弱状态是否改变 ICD 对全因死亡率的治疗效果。
该研究纳入了 1676 名参与者（平均年龄：59±12 岁，23%为女性），低虚弱组 FI 的中位数为 0.30（IQR：0.23-0.37），高虚弱组为 0.54（IQR：0.47-0.60）。在调整后的 Cox 模型中，基线虚弱状态显著改变了 ICD 治疗的效果（P=0.047）。按虚弱状态进行分层分析，ICD 治疗与低虚弱负担患者的全因死亡率降低相关（HR：0.56；95%CI：0.40-0.78），但与高虚弱负担患者无关（HR：0.86；95%CI：0.68-1.09）。
基线虚弱状态修饰了 ICD 治疗的效果，在低虚弱负担的 HFrEF 患者中观察到显著的死亡率获益，但在高虚弱负担的患者中则没有。
