Restrictive vs liberal red blood cell transfusion strategies in patients with acute myocardial infarction and anemia: Rationale and design of the REALITY trial

Abstract

Background Anemia is common in patients with acute myocardial infarction (AMI), and is an independent predictor of mortality. The optimal transfusion strategy in these patients is unclear. Hypothesis We hypothesized that a “restrictive” transfusion strategy (triggered by hemoglobin ≤8 g/dL) is clinically noninferior to a “liberal” transfusion strategy (triggered by hemoglobin ≤10 g/dL), but is less costly. Methods REALITY is an international, randomized, multicenter, open‐label trial comparing a restrictive vs a liberal transfusion strategy in patients with AMI and anemia. The primary outcome is the incremental cost‐effectiveness ratio (ICER) at 30 days, using the primary composite clinical outcome of major adverse cardiovascular events (MACE; comprising all‐cause death, nonfatal stroke, nonfatal recurrent myocardial infarction, or emergency revascularization prompted by ischemia) as the effectiveness criterion. Secondary outcomes include the ICER at 1 year, and MACE (and its components) at 30 days and at 1 year. Results The trial aimed to enroll 630 patients. Based on estimated event rates of 11% in the restrictive group and 15% in the liberal group, this number will provide 80% power to demonstrate clinical noninferiority of the restrictive group, with a noninferiority margin corresponding to a relative risk equal to 1.25. The sample size will also provide 80% power to show the cost‐effectiveness of the restrictive strategy at a threshold of €50 000 per quality‐adjusted life year. Conclusions REALITY will provide important guidance on the management of patients with AMI and anemia.

Effect of a Restrictive vs Liberal Blood Transfusion Strategy on Major Cardiovascular Events Among Patients With Acute Myocardial Infarction and Anemia

“…Fourth, this report was limited to analysis of 30-day outcomes. Longer follow-up to 1 year is being accrued and will allow evaluation of the potential long-term effects of the 2 transfusion strategies as well as assessment of potential quality of life and incremental cost-utility ratio differences between the groups …”

Treatment of acute upper gastrointestinal bleeding occurred after percutaneous coronary intervention for acute myocardial infarction in patients with acute renal impairment: a case report

“…The REALITY trial provided a reasonable answer. The trial confirms that a ‘restrictive’ transfusion strategy (triggered by hemoglobin ≤80 g/L) is clinically noninferior to a ‘liberal’ transfusion strategy (triggered by hemoglobin ≤100 g/L), but is less costly [ 17 ]. Because the patient temporarily had no active gastrointestinal bleeding, clopidogrel antiplatelet aggregation therapy was added on the third day after the occurrence of UGI bleeding.…”

Effect of Restrictive or Liberal Blood Transfusion on Major Cardiovascular Events in Patients With Acute Myocardial Infarction and Anemia—Reply

“…This represents the majority of patients (60.8%) in the restrictive transfusion group. Second, the hemoglobin difference between groups at discharge was 1.4 g/dL, well exceeding our protocol-planned between-group difference of 1 g/dL . Third, 17.4% of the patients in the liberal transfusion group had ongoing active bleeding after randomization, which explains why some patients in the liberal transfusion group were discharged with hemoglobin levels below 11 g/dL.…”

“…In Reply In their comments about the results of the REALITY trial, Dr Sato and colleagues point out a lower incidence of ALI in the restrictive vs liberal transfusion group and postulate that this finding may be related to transfusion. However, the number of lung injury events was small (8 in total), and the REALITY trial, similar to most trials, was not powered to assess adverse events . For that reason, and given the potential for type I error with multiple comparisons, we did not provide P values for between-group comparisons of safety outcomes.…”