A Retrospective Review to Determine If Children with Sickle Cell Disease Receive Hydroxyurea Monitoring

Introduction: Sickle cell disease guidelines recommend that patients on hydroxyurea receive monitoring at least every 2–3 months, but it is unknown if this occurs in clinical practice. This study aimed to determine if patients with sickle cell disease at Nationwide Children’s Hospital had at least 4, in-person monitoring visits during a 12-month period and if frequent monitoring was associated with hydroxyurea adherence and clinical outcomes. Methods: We performed a retrospective analysis of children on hydroxyurea for at least 12 months during 2010–2015. Patients’ demographics, laboratory studies, prescriptions, and number of hydroxyurea and acute visits were recorded from their 12-month period that met eligibility criteria. Patients were considered frequently monitored if they had ≥ 4 hydroxyurea visits and adherent if they had prescriptions for hydroxyurea for ≥ 80% of the days in their 12-month period. Results: Seventy-four children met the eligibility criteria and 57 (77%) had frequent monitoring. The most common reason for not obtaining frequent monitoring was missing a scheduled appointment. A greater proportion of frequently monitored patients were adherent to hydroxyurea (66.7% versus 17.7%; P < 0.001), and they had significantly fewer acute visits (median 1 versus 2 visits; P = 0.032) compared with infrequently monitored patients. Conclusions: Our study shows that most children on hydroxyurea at Nationwide Children’s Hospital received frequent monitoring and that it was associated with improved adherence and outcomes. Our results suggest that frequent in-person monitoring could be an opportunity to identify poorly adherent patients. These data inform our next quality improvement initiative that will maximize adherence to these monitoring guidelines.