Duke 2008 | ASHE | Equity and Efficiency in Health and Healthcare

Background. In October 2004, the U.S. Food and Drug Administration (FDA) directed pharmaceutical manufacturers to add a black-box warning (BBW) to SSRI-class antidepressants describing an increased risk of suicidality in children and adolescents. This decision elicited controversy within the scientific community reflecting a fundamental trade-off associated with weighing risks against benefits under conditions of scientific uncertainty. Supporters of the FDA's decision argued that evidence of elevated risks of suicidality linked to antidepressant use in youth was sufficiently serious to warrant informing providers and consumers. Critics countered that the FDA action would broadly reduce the use of an effective treatment for depression, thereby producing poorer outcomes (including some upward pressure on the risk of suicide) in an underserved population. We examined the impact of FDA regulatory policy on depression treatment for children, adolescents and adults. We also plan to examine whether this decline in antidepressant use was associated with a change in medically treated suicide attempts.

Methods. We use the Medical Expenditure Panel Survey (MEPS) and Medstat's Marketscan database, a national sample of privately insured individuals to address these issuess. Our model suggests a novel approach to estimating the effects of new information. Instead of a traditional pre-post regulation design, we create a set of measures that incorporate exposure to relevant media coverage of the risk of antidepressant use over time. This approach is useful when information dissemination precedes a regulatory action, making the precise date of the action unclear or when several relevant regulatory events occur close in time. We create flow (current volume) and stock (accumulated volume) variables representing news stories and the scientific literature. We construct episodes of treatment using claims data for the purposes of assessing treatment choice.

Results. First, we examine changes in treatment patterns. We find that use of prescription drugs included in the FDA's black box warning (BBW) by children and adolescents declined by approximately 35 percent for those newly diagnosed with depression. Over this period, we also find a substantial increase in the use of fluoxetine in newly diagnosed cases. This is the only drug in this class approved by the FDA for treatment of depression in children. In the BBW, the FDA specifically noted the need for monitoring patients initiating antidepressant treatment. We examine whether receipt of medication monitoring increased among youth prescribed antidepressants. Contrary to our expectations, we find no significant increases in outpatient visits or monitoring.

We plan to use an instrumental variables strategy using the timing of media coverage of FDA action and MSA of individual to predict antidepressant use. Preliminary first stage regressions suggest this is a valid strategy (F-test>10.0), although results are not yet available.

Conclusions. These results suggest that the impact of the FDA action, and the controversy generally, reduced use of an effective treatment.