Assessing the State of Stroke Risk, Prevention in Patients With SCD

Heme Today spoke with Theodore Wun, MD, Chief of the Division of Hematology and Oncology at the University of California Davis Health in Sacramento, California.

Dr. Wun is the senior author of a study assessing trends in stroke incidence among California patients with sickle cell disease (SCD) since the 1998 Stroke Prevention Trial in Sickle Cell Anemia (STOP). The study was an analysis of longitudinal emergency department data from 1991 to 2019 for a large cohort of patients. Its findings were recently published in Blood.

Although STOP established standards of care for stroke in patients with SCD, the study authors found that stroke incidence had increased in both adult and pediatric patients since the trial. After initially decreasing following STOP, stroke rates among children have risen over the last decade. Moreover, adults aged in their 40s to 60s have elevated rates compared to children.

“Now the pediatricians do such a good job of bringing patients with sickle cell disease into adulthood, and we now take care of them on the adult side, they have accumulating complications and organ damage that we are now seeing in those patients who are older,” Dr. Wun elaborated.

Dr. Wun said the study results underscore that the clinical risk factors for stroke screened for in the general population, especially high blood pressure and lipid levels, should be aggressively addressed in patients with SCD. Currently, clinicians who manage stroke in patients with SCD do not adequately apply the approaches found by large trials to be effective.

“I think we know how to reduce stroke risk based on those risk factors, and we know how to reduce stroke risk in children, too, based on the STOP study. It’s paying attention to why, perhaps, aren’t people following the guidelines,” Dr. Wun explained.

In an email correspondence with Heme Today to comment on the study, first author Olubusola Oluwole, MD, of the University of Pittsburgh School of Medicine in Pennsylvania, remarked that among pediatric patients with SCD, rising stroke rates may also be linked to diminished use of hydroxyurea and other disease-modifying therapies.

“The recent withdrawal of voxelotor from the market makes the situation particularly critical, underscoring the urgent need for additional studies to develop safe and effective disease-modifying therapies for this population,” Dr. Oluwole wrote.