Table 3.
Relationship between release of U.S. FDA pregnancy warning and rates and trends of antidepressant prescribing (per 1,000 persons) during pregnancy, 2002–2005a
| Pre-Warning Period (January 1, 2002 – May 31, 2004) | Post-Warning Period (October 1, 2004 – July 31, 2005) | |||
|---|---|---|---|---|
| Antidepressant prescribing at the start of observation period, N prescriptions per 1,000 womenb | Rate of change in antidepressant use, N prescriptions per 1,000 women/month (95% CI)c | Magnitude of change in October 2004, N prescriptions per 1,000 women (95% CI)d | Rate of change in antidepressant use, N prescriptions per 1,000 women/month (95% CI)e | |
| Any antidepressant | 34.51 | 0.46 (0.41, 0.52) | −3.81 (−7.17, −0.44) | −1.48 (−1.62, −1.35) |
| SSRI | 25.46 | 0.25 (0.20, 0.30) | −2.26 (−4.27, −0.25) | −0.89 (−0.93, −0.85) |
| Non-SSRI | 9.19 | 0.21 (0.19, 0.23) | −1.00 (−2.12, 0.13) | −0.70 (−0.73, −0.68) |
Change associated with FDA pregnancy warning represents the estimated effect of the U.S. FDA pregnancy warning (issued June 9, 2004), using a 4 month transition period (June 1, 2004 – September 30, 2004) that also encompassed Health Canada pregnancy advisory.
Represents the estimated number of antidepressant prescriptions per 1,000 pregnant women in January 2004.
Represents the rate of change (slope) in antidepressant prescribing during the pre-warning period. The positive values (with 95% confidence intervals [CIs]) are rates of increase, expressed as number of prescriptions per 1,000 pregnant women per month.
Represents the difference between the estimated antidepressant prescribing rate (number of prescriptions per 1,000 pregnant women) with the FDA warning in place, minus the estimated prescribing rate without the FDA warning, in October 2004. The estimated prescription rate without the FDA warning was based on extrapolating pre-warning trends in antidepressant prescribing.
Represents the linear rate of change (slope) in antidepressant prescribing during the post-warning period. The negative values (with 95% confidence intervals [CIs]) are rates of decrease, expressed as number of prescriptions per 1,000 pregnant women per month.