Department of Epidemiology, University of Pittsburgh, Pittsburgh, Pennsylvania (G.T.P., S.A.S.).
Division of General Internal Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey (J.L.C.).
Ann Intern Med. 2024 Nov;177(11):1489-1498. doi: 10.7326/M24-0571. Epub 2024 Oct 1.
The optimal hemoglobin threshold to guide red blood cell (RBC) transfusion for patients with acute myocardial infarction (MI) and anemia is uncertain.
To estimate the efficacy of 4 individual hemoglobin thresholds (<10 g/dL [<100 g/L], <9 g/dL [<90 g/L], <8 g/dL [<80 g/L], and <7 g/dL [<70 g/L]) to guide transfusion in patients with acute MI and anemia.
Prespecified secondary analysis of the MINT (Myocardial Ischemia and Transfusion) trial using target trial emulation methods. (ClinicalTrials.gov: NCT02981407).
144 clinical sites in 6 countries.
3492 MINT trial participants with acute MI and a hemoglobin level below 10 g/dL.
Four transfusion strategies to maintain patients' hemoglobin concentrations at or above thresholds of 10, 9, 8, or 7 g/dL. Protocol exceptions were permitted for specified adverse clinical events.
Data from the MINT trial were leveraged to emulate 4 transfusion strategies and estimate per protocol effects on the composite outcome of 30-day death or recurrent MI (death/MI) and 30-day death using inverse probability weighting.
The 30-day risk for death/MI was 14.8% (95% CI, 11.8% to 18.4%) for a <10-g/dL strategy, 15.1% (CI, 11.7% to 18.2%) for a <9-g/dL strategy, 15.9% (CI, 12.4% to 19.0%) for a <8-g/dL strategy, and 18.3% (CI, 14.6% to 22.0%) for a <7-g/dL strategy. Absolute risk differences and risk ratios relative to the <10-g/dL strategy for 30-day death/MI increased as thresholds decreased, although 95% CIs were wide. Findings were similar and imprecise for 30-day death.
Unmeasured confounding may have persisted despite adjustment.
The 30-day risks for death/MI and death among patients with acute MI and anemia seem to increase progressively with lower hemoglobin concentration thresholds for transfusion. However, the imprecision around estimates from this target trial analysis precludes definitive conclusions about individual hemoglobin thresholds.
National Heart, Lung, and Blood Institute.
指导急性心肌梗死（MI）合并贫血患者进行红细胞（RBC）输血的最佳血红蛋白阈值尚不确定。
评估 4 个个体血红蛋白阈值（<10 g/dL [<100 g/L]、<9 g/dL [<90 g/L]、<8 g/dL [<80 g/L]和<7 g/dL [<70 g/L]）指导急性 MI 合并贫血患者输血的疗效。
使用目标试验仿真方法对 MINT（心肌缺血和输血）试验进行预先指定的二次分析。（ClinicalTrials.gov：NCT02981407）。
6 个国家的 144 个临床地点。
3492 名 MINT 试验参与者，急性 MI 且血红蛋白水平低于 10 g/dL。
四种输血策略，将患者的血红蛋白浓度维持在 10、9、8 或 7 g/dL 以上的阈值。对于特定的不良临床事件，允许协议例外。
利用 MINT 试验的数据来模拟 4 种输血策略，并使用逆概率加权估计 30 天内死亡或复发性 MI（死亡/MI）和 30 天内死亡的协议效果。
<10 g/dL 策略的 30 天死亡/MI 风险为 14.8%（95%CI，11.8%至 18.4%），<9 g/dL 策略为 15.1%（CI，11.7%至 18.2%），<8 g/dL 策略为 15.9%（CI，12.4%至 19.0%），<7 g/dL 策略为 18.3%（CI，14.6%至 22.0%）。尽管 95%CI 较宽，但随着阈值降低，30 天死亡/MI 的绝对风险差异和风险比相对于<10 g/dL 策略均增加。30 天死亡的结果相似且不精确。
尽管进行了调整，但可能仍存在未测量的混杂因素。
急性 MI 合并贫血患者的 30 天死亡/MI 和死亡风险似乎随着输血的血红蛋白浓度阈值降低而逐渐增加。然而，来自该目标试验分析的估计值的不精确性使得无法对个体血红蛋白阈值做出明确结论。
美国国立心肺血液研究所。
