FORT LAUDERDALE, Fla. – A study of sickle cell patients at a clinic in the Bronx found that upwards of 75% of them get a prescription for hydroxyurea to improve hemoglobin levels, but that one-third have discontinued use for various reasons, according to results reported at the 13th annual Foundation for Sickle Cell Disease Research symposium here.
“The results identify variability in reported side effects and reasons for discontinuation, and highlight the importance of clear communication between providers and patients to discuss the benefits and challenges of hydroxyurea,” said Caterina Minniti, MD, professor of clinical medicine and pediatrics at Einstein College of Medicine and director of the Sickle Cell Center for Adults at Montefiore Hospital, Bronx, N.Y. The study analyzed self-reporting surveys completed by 224 adult outpatients in the Montefiore sickle cell clinic, and then verified the data in the electronic medical record, Dr. Minniti said. She noted, “Our population is unique in the Bronx in that we have a high percentage of Hispanic patients.” They comprised 24.1% of the study population.
“We found that 77.2% of the patients have ever been prescribed hydroxyurea,” she said. “That was really great.” Also, 91% of those with severe genotypes of SCD had been prescribed the drug; 68% of them were still taking hydroxyurea at the time of the survey, she said. Among patients with the mild genotype, 42.1% had been prescribed hydroxyurea and half were still on it when they completed their surveys.
When the survey evaluated how long patients had been taking the drug, she said, “That’s where I start to get concerned.” About half – 48.6% – had taken the drug for one to five years, “which is a very short period of time,” Dr. Minniti said. Another 15% were on hydroxyurea for less than a year, 23% for 5 to 10 years and 19% for 10 years or more.
The study drilled down into reasons why patients discontinued the drug. Side effects were cited by 24.6% (n=15). They include fatigue, hair loss, and GI upset. Other reasons include perceived ineffectiveness (16.4%, n=10); physician direction (14.8%, n=9), and reproductive health and ulcer formation (each at 8.2%, n=5).
“Many patients perceive ineffectiveness of hydroxyurea in the short term, but the benefits of hydoxyurea stem from chronic use over the long term,” Dr. Minniti said. She noted that some patients discontinued the drug for legitimate medical indications, “such as pregnancy and breast feeding, but were not restarted afterward.”
Dr. Minniti disclosed relationships with Novartis, Global Blood Therapeutics, Teutona, Bluebird Bio, GBT and Bayer.
SOURCE: Minniti C, et al. Abstract no. JSCDH-D-19-00058. Foundation for Sickle Cell Disease Research Symposium; Fort Lauderdale, Fla.; June 9, 2019.