Hemoglobin concentrations in the high normal range in patients with anemia due to chronic kidney disease result in an excess risk of major adverse events, reported Arintaya Phrommintikul, MD, and colleagues from Monash University, Melbourne, Australia.
Adverse events include death, arteriovenous access thrombosis, and poorly controlled hypertension.
The investigators conducted a meta-analysis of 9 randomized controlled studies that enrolled 5143 patients treated with recombinant human erythropoietin.
Patients in the group targeted for a higher hemoglobin level (120-160 g/L) had a higher risk for all-cause mortality than patients in the lower hemoglobin target group (< 120 g/L) (risk ratio 1.17, P = 0.031).
There was also a higher risk for arteriovenous access thrombosis (risk ratio 1.34, P=0.0001) as well as a significantly higher risk of poorly controlled blood pressure (risk ratio 1.27, P=0.004) in the higher hemoglobin target group. The incidence of myocardial infarction was similar in the two groups.
Current guidelines recommend the maintenance of hemoglobin concentrations at 110 g/L or higher, based mainly on evidence of benefit in quality-of-life measures.
Current guidelines do not include an upper limit for the target hemoglobin concentration. The authors suggest that an upper limit should be added in future revisions of guideline recommendations.
The study was published in the 3 February 2007 issue of Lancet.