Is patient compliance a significant barrier to hydroxyurea treatment of children with sickle cell disease?

Many hem/oncs believe that their patients will be not be compliant and do not prescribe the therapy.

Our research surveyed the membership of the American Society of Pediatric Hematology and Oncology, the largest pediatric hematology/oncology professional organization in the United States and Canada. We sought to evaluate the practice patterns of hydroxyurea use and identify barriers to its use. Thirty-one percent (n=350) of physicians contacted completed the survey, and 63% (n=220) of those said that they care for children with sickle cell disease.

We found that only 8% of providers have 50% to 90% of their sickle cell disease patients on hydroxyurea therapy, 54% have 10% to 30% of their patients on the therapy, and 10% have fewer than 10% of their sickle cell disease patients on hydroxyurea.

Amanda M. Brandow

The most common reason that physicians do not prescribe hydroxyurea is that they believe their patients will not be compliant both with the medication and recommended laboratory monitoring. Among those physicians who do not prescribe hydroxyurea to eligible patients, 86% said their patients won’t be compliant with the drug, 85% said that patients will not return for needed blood tests, and 85% said the eligible female patients will not be compliant contraception while on the drug. Nearly 30% do not prescribe the drug due to concerns about its carcinogenic potential.

Surprisingly, 11% said that they do not have the time or resources to explain the risks and benefits to their eligible patients, 12% do not use the treatment because it is not approved by the FDA for children, and 11% said they do not think the drug is effective.

The criteria that most doctors use to prescribe hydroxyurea are acute chest syndrome and pain. Those providers who account for the frequency of the child’s pain at home, and not just the events that bring the child to the hospital, were significantly more likely to prescribe the drug.

The more data we have that shows hydroxyurea is safe and effective, that the cost/benefit ratio is good, and that using it reduces both health care utilization and improves the pain experienced by children at home, will hopefully lead to better utilization of the therapy. In addition, it is important for physicians to determine the potential reasons for non-compliance, whether it be the patient’s fear of side effects or potentially access to care issues. In the end, interactions between the patient and the physician may ultimately determine whether the patient is started on the drug or not.

Amanda M. Brandow, DO, MS, is Assistant Professor at the Medical College and Children’s Research Institute at the Children’s Hospital of Wisconsin.

Compliance if often suboptimal among patients with sickle cell disease.

Our research looked at how patient compliance with hydroxyurea can improve both clinical and economic outcomes. For our analysis, we looked at retrospective claims of enrollees in the North Carolina Medicaid program between June 1999 and August 2008. Inclusion criteria were one or more claims with a diagnosis for sickle cell disease, continuous health plan enrollment for 12 months or longer prior to and following initiation of hydroxyurea therapy, and two or more prescriptions for hydroxyurea in the year following the initiation of the therapy.

We found that only 35% of patients were adherent with therapy, meaning that they filled enough prescriptions to supply them with hydroxyurea for 80% of the days in one year of therapy. For those patients who were compliant, there was a significant reduction in both all-cause and sickle cell disease-related inpatient and emergency department costs.

Sarah O’Brien

Although this is a poorly studied topic, there are several theories about why patients and their parents do not comply with the therapy. One theory is that it is difficult to get a prescription filled every month, to go to the clinic much more often, and to get lab studies done. We know that many families with sickle cell disease are coming from stressed homes and find it difficult to get to the clinic.

Another theory is that people often do not continue to take a drug if they do not feel better when they are taking it. Hydroxyurea is a medication where you will not see the effects for months to years later. Some of the most important effects are prevention of organ damage and that takes years to appreciate.

Other studies have found that parent perception is a factor in compliance. If the parents feel that their child has severe sickle cell disease, they are more interested in trying hydroxyurea.

Because the first few months are so crucial for this therapy, one center makes frequent phone calls during the first few weeks, asking how the treatment is going, explaining how the therapy is important for long-term health, and encouraging the patient and parents to continue the therapy. This is definitely not a medication where you can just hand the patient the prescription and send them on their way without close follow-up and support.

Sarah O’Brien, MD, MSc, is an investigator in the Center for Innovation in Pediatric Practice and Assistant Professor in the Department of Pediatrics at The Ohio State University College of Medicine in Columbus.