Prophylactic use of hydroxyurea in children with sickle cell disease (SCD) significantly reduces middle cerebral artery blood velocity as assessed by transcranial doppler ultrasound (TCD), thus potentially reducing stroke risk in these patients, as published in the Journal of Clinical Medicine. The researchers provided further evidence supporting the use of hydroxyurea in patients with SCD, even starting in infancy.

“Primary prophylaxis has, over time, taken on two forms: lifelong chronic blood transfusions to maintain a reduced percentage of sickle hemoglobin (HbS) or [hydroxyurea] therapy initiated after an initial period of chronic blood transfusions,” the authors explained.

“We tested the primary hypothesis that . . . maximum tolerated dose hydroxyurea therapy in children with SCD would be associated with a decrease of >10% [middle cerebral artery] [time averaged mean of maximum velocities (TAMX)] (surrogate for stroke risk) compared with children receiving no treatment.”

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The research team assessed the TAMX measurements via TCD in 329 patients with SCD aged 2 to 25 years at a single center in Detroit, Michigan in 2020. All TCDs were performed between the ages of 2 years and 16 years. There were 111 patients who had been on hydroxyurea at the time of at least one TCD, and 218 had never received hydroxyurea treatment.

The results found middle cerebral artery TAMX velocities that were 11.2% lower in patients who had received hydroxyurea treatment than in those who had not, representing a significant reduction. Given that chronic transfusions are indicated for TAMX scores >2 m/s, the difference is clinically significant for these patients. The team concluded that their results further support the early use of prophylactic hydroxyurea in children with SCD.


Peine BR, Callaghan MU, Callaghan JH, Glaros AK. Prophylactic hydroxyurea treatment is associated with improved cerebral hemodynamics as a surrogate marker of stroke risk in sickle cell disease: a retrospective comparative analysis. J Clin Med. 2022;11(12):3491. doi:10.3390/jcm11123491