Children with sickle cell disease had improved lung function after treatment with hydroxyurea, according to a study presented at the American Thoracic Society (ATS) 2016 International Conference. 

Hydroxyurea is known to reduce the incidence of acute sickle-related events such as pain and acute chest crises (ACS). Anya McLaren, MD, FRCP, MSc, The Hospital for Sick Children, Toronto, Canada, and coauthors, hypothesized that hydroxyurea could prevent the expected annual decline in pulmonary function in children with sickle cell disease.  

A total of 94 study patients (aged 6-20 years) were initiated on hydroxyurea as determined by the treating hematologist and were followed over a 4-year period; specifically at Months 3, 6, 9, 12, 24, 36, and 48, after initiation. At each time point, the patients’ complete blood count, hemoglobin F, liver and renal function tests were monitored. Pulmonary function tests (PFT) were obtained up to a median of 3.68 years before and 3.84 years after hydroxyurea initiation. 

Related Articles

The study authors found a greater than 1-fold increase in measured hemoglobin F for each year of therapy. The annual rate of decline in predicted FEV1 and FEF25-75 prior to hydroxyurea initiation was -1.98% per year (95% CI: -2.57, -1.39) and -3.59% per year (95% CI: -4.43, -2.75), respectively. After therapy, however, there was a significant improvement in the annual decline of these parameters to -1.28% per year (95% CI: -1.79, -0.76) and -2.88% per year (95% CI: -3.49, -2.28), respectively. These changes were independent of the age and time from hydroxyurea therapy start date. 

No signifiant changes in TLC, FVC, or FEV1/FVC predicted measurements after starting hydroxyurea were seen. 

Dr. McLaren was able to conclude that hydroxyurea therapy improved pulmonary function decline in children with sickle cell disease. Study findings support the use of hydroxyurea in this population and, “In combination with the established safety data, it hopefully will promote physician recommendations for hydroxyurea initiation and encouragement of compliance.”

For more information visit