BOCA RATON, FLA. — The black box warning of potential increased suicidality among pediatric patients treated with antidepressants spurred an overall 10% decrease in prescriptions in the ensuing year, according to a study of a large managed care database.
There were 68,121 prescriptions for patients 17 years old and younger in the United Healthcare database in the year before the October 2004 bilack box warning, compared with 61,561 afterward. This 10% decrease was statistically significant (P < .001), Christine Thomason, Ph.D., said in an interview at a poster session at a meeting of the New Clinical Drug Evaluation Unit sponsored by the National Institute of Mental Health.
“We expected it to go down, but I want to make it clear that access to effective treatment is so important,” said Dr. Thomason, director of the pediatric CNS division of i3 Research.
Dr. Thomason and her associates assessed the data by individual agent(s) prescribed, antidepressant drug class, new prescriptions only, and patient age.
“Fluoxetine use increased. It is the only approved medication for major depressive disorder in children,” Dr. Thomason said. Postwarning prescriptions increased 9% for fluoxetine, while prescriptions decreased 19% for sertraline (Zoloft) and 29% for venlafaxine (Effexor).
When researchers specifically looked at only selective and nonselective serotonin reuptake inhibitors, the overall decrease was 12%. Regarding new prescriptions, the number fell 20% in the year after the black box warning, Dr. Thomason said. “It is likely that patients taking antidepressants are maintained on that treatment, but physicians are prescribing antidepressants at a lower rate for new patients,” the authors wrote.
The highest decreases for any antidepressant prescription were among younger patients. For example, prescriptions decreased 18% (from 466 before the warning to 383 afterward) among those 0–4 years old. Prescriptions dropped 15% among patients 5–9 years old; 11% among 10- to 14-year-olds; and 7% among 15- to 17-year-olds. About half of the pediatric patients in the study fell in the 15- to 17-year-old group.
Sex was almost evenly split between prewarning and postwarning groups. Psychiatric diagnoses (all counts at all encounters) were likewise similar between groups. For example, depressive disorder accounted for 30% of the prewarning encounters vs. 29% post warning; attention-deficit hyperactivity disorder accounted for 24% in each group; and anxiety/general anxiety disorder accounted for 10% of prewarning and 11% of postwarning encounters.
All data in the study were deidentified to protect patient privacy. Data were limited to outpatient retail, mail order, and specialty pharmacy claims.
The researchers plan to expand the study to cover more than 1 year before and after the black box warning. In addition, plans include a comparison of prescribing habits of general practitioners vs. child psychiatrists.
“We also want to see if there is any seasonal variation in prescriptions—such as increased use during the holidays or lower use during the summertime,” Dr. Thomason said at the meeting, which was cosponsored by the American Society for Clinical Psychopharmacology.