What drives transcranial Doppler velocity improvement in paediatric sickle cell anaemia: analysis from the Sickle Cell Clinical Research and Intervention Program (SCCRIP) longitudinal cohort study

Children with sickle cell anaemia (SCA) and conditional transcranial Doppler (TCD) flow velocities (conditional: 170-199 cm/s; normal: <170 cm/s) have an increased risk of stroke. The Sickle Cell Clinical Research and Intervention Program (SCCRIP), a lifetime observational study, assessed the influence of haematological markers on TCD velocities. In children (<= 16 years) with SCA (HbSS/HbS beta(0)-thalassaemia) and conditional TCD velocities (n = 32), increases in haemoglobin and in fetal haemoglobin after hydroxyurea initiation were significantly associated with decreases in TCD velocities. The benefit of pharmacological intervention to increase haemoglobin and fetal haemoglobin and normalise TCD velocities was demonstrated in this real-world dataset.

Automated summary

Children with sickle cell anaemia and conditional TCD flow velocities are at increased risk of stroke. The SCCRIP study demonstrated that increases in haemoglobin and fetal haemoglobin can lead to decreased TCD velocities in these children. Pharmacological intervention to increase haemoglobin and fetal haemoglobin was shown to normalize TCD velocities in this real-world dataset.