Patients are living longer, but trial evidence is lacking for the many complications of sickle cell diseases, a new Cochrane review has found.

The review authors looked at past trials that have used blood transfusions to prevent complications such as stroke and painful crisis episodes. 

Red blood cell transfusions are used to treat complications, but they also carry risks such as iron overload and antibody formation.

A total of 17 studies were considered by the review, which was co-authored by Lise Estcourt, director of transfusion at NHS Blood and Transfusion, Alvin Katumba and Carolyn Dorée of the Radcliffe Department of Medicine at the University of Oxford.

It found there is a lack of trial evidence for many complications of sickle cell diseases.

“To provide the best care for patients who are now living longer than ever, we need better trial evidence about how and when to use red blood cell transfusions to treat people with sickle cell disorder,” Estcourt said.

The authors found that while there was good evidence that blood transfusions reduce the risk of stroke in children, there is a lack of high-quality evidence for adults. This was of “particular concern”, they said, as people with sickle cell diseases are living longer and may experience more of the chronic complications of these conditions.

It is “imperative to have a better understanding of the comparative benefits and harms of red blood cell transfusions,” they added. In addition, well-designed trials are needed that report on patient-relevant outcomes as well as quality of life.