Transfusion Trigger Trial for Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair (FOCUS): The Principal Results

Red blood cell transfusion is commonly administered after surgery. It has been suggested that patients with underlying cardiovascular disease are especially vulnerable to anemia and may benefit from transfusion to higher hemoglobin levels. However, red blood cell transfusion is costly and associated with uncommon but clinically important adverse effects. Thus, the indications for red blood cell transfusion are controversial. The aim of this NHLBI-sponsored randomized clinical trial was to determine whether higher blood transfusion thresholds improve functional recovery and reduce mortality and morbidity in patients with underlying cardiovascular disease or cardiovascular risk factors.

We enrolled patients who were 50 years of age or older, underwent surgery for hip fracture, had a history of or risk factors for cardiovascular disease, and had postoperative hemoglobin < 10 g/dL. We randomly allocated patients to a transfusion threshold of 10 g/dL, or to receive transfusion when anemia symptoms occurred; transfusion was permitted if hemoglobin was < 8 /g dL. The primary outcome was death or the inability to walk across a room without human assistance at 60-Day follow-up. Secondary outcomes included 60-Day follow-up mortality, fatigue, falls, readmission to the hospital, and function.

We enrolled 2016 patients from 47 medical centers in North America. The age of the subjects varied from 51-103; mean age was 81.6 and 24% were male. 82% had hypertension, 40% had coronary artery disease, 25% had diabetes mellitus and 18% had history of cancer. The mean hemoglobin concentration prior to randomization was 9.0 g/dL (standard deviation +/‐ 0.8). The hemoglobin concentration prior to transfusion in 10 /g dL group was 9.2 g/dL (standard deviation +/‐ 0.5) and in symptomatic group 7.9 g/dL (standard deviation +/‐ 0.5). 10g/dL arm was transfused median 2 units (interquartile range 1,2), while the symptomatic group was transfused median 0 units (interquartile range 0,1). In the 10 g/dL group 35% (40% men, 33% women) were dead or unable to walk without human assistance and for symptomatic group 35% (32% men, 35% women); odds ratio = 1.03, 95% confidence interval 0.85 to 1.23; difference = 0.6%, 95% confidence interval = -3.6 to 4.8%. In the 10 g/dL group 7.6% were dead on 60-Day follow-up and for symptomatic group 6.5%; odds ratio = 1.19, 99% confidence interval 0.76 to 1.86; difference = 1.1%, 99% confidence interval = -1.8 to 4.1%. The frequency of readmission to the hospital, falls, and the fatigue score were similar between the transfusion groups.

Symptomatic transfusion conserved blood and had no adverse effects on ability to walk, 60-Day follow-up mortality, falls, readmission rates, or fatigue in this high-risk group of elderly patients with underlying cardiovascular disease or cardiovascular risk factors.

Magaziner: Merck: Research Funding; Novartis: Research Funding; Amgen: Consultancy; Lilly: Consultancy.