Changes in US antidepressant and antipsychotic prescription patterns during a period of FDA actions

Abstract

Purpose: To determine if paroxetine versus non-paroxetine selective serotonin reuptake inhibitors (SSRIs) prescribing changed after the June 2003 FDA Paroxetine Public Health Advisory (PPHA) and if antidepressant and antipsychotic prescribing changed after the February 2004 FDA Advisory Committee Meeting (FDACM).

Methods: Ecologic analysis using estimates of patients dispensed antidepressants and antipsychotics, census data, and promotional spending data. Data sources were SDI: Vector One(R), US Census, and IMS Health(R). Measures were monthly use levels (number of patients dispensed antidepressants, antipsychotics, paroxetine, and non-paroxetine SSRIs prescriptions by age group per population count). Percent changes pre- to post-PPHA were used to assess changes in paroxetine versus non-paroxetine SSRIs prescribing. Interrupted time series (ITS) analysis was performed to examine use level changes post-FDACM by drug groups (all antidepressants and all antipsychotics).

Results: Post-PPHA mean paroxetine use levels decreased for all age groups (range: 5.5-34.1%). Mean non-paroxetine SSRIs use levels increased (range: 4.6-17.1%). Post-PPHA changes were greatest for 6-12 and 13-17 year olds. Decreased mean antidepressant drug use levels from pre- to post-FDACM were observed in all groups under 25 years old. A statistically significant decrease in the slopes from pre- to post-FDACM was observed for persons aged 13-17 and 18-24 years. The difference between the forecasted mean use level and the observed mean use level (in 12-month intervals) was statistically significant for all ages combined (-107.26; 95% CI: -166.32, -48.20) and 1-5 (-3.1; 95% CI: -4.62, -1.58), 6-12 (-36.02; 95% CI: -62.92, -9.12) and 25 years, and older groups (-83.17; 95% CI: -153.95, -12.39). For all age groups, decreases in the slopes of antipsychotic drugs use from pre- to post-FDACM were observed, although these slope changes were not statistically significant. The difference between the forecasted mean antipsychotic drugs use level and the observed mean use level (in 12-month intervals) was statistically significantly lower for all age groups.

Conclusions: Antidepressant use changed post-PPHA and -FDACM, with a differential pattern by age. There was no evidence of increased antipsychotic use post-FDACM. Ecologic data cannot determine if changes were due to depression not treated with medications or the prescribing of fewer antidepressants for other conditions.