Assessing Responsiveness of Health Systems to Drug Safety Warnings

In 2011-2012 the U.S. Food and Drug Administration (FDA) issued safety announcements cautioning providers against prescribing high doses of citalopram given concerns for QT prolongation. The authors evaluated Veterans Affairs (VA) national trends in citalopram use and dose compared with alternative antidepressants after the FDA warnings.
Time series analyses estimated the effect of the FDA warnings on citalopram and other antidepressant across three periods: before the first FDA warning in August 2011, after the 2011 FDA warning until the second warning in March 2012, and after the 2012 FDA warning. In a National VA health system, adult VA outpatients prescribed citalopram or alternative antidepressants from February 2010 to September 2013 were studied. Outpatient use of high-dose citalopram (>40 or >20 mg daily in adults aged > 60 years) including the proportion of patients prescribed citalopram and difference between study periods.
Between the first and second FDA warnings, among patients aged 18-60, high-dose citalopram use decreased by 2.0% per month (p < 0.001) and by 1.9% per month (p < 0.001) for older adults. After the second FDA warning in 2012, 30.7% of older patients remained on doses higher than the newly recommended dose of 20 mg. Reductions in overall use of citalopram were accompanied by significant increases in prescriptions of alternative antidepressants, with sertraline most widely prescribed.
Although trends in high-dose citalopram use declined after the 2011-2012 FDA warnings, roughly one-third of older adults still remained on higher than recommended doses. Concomitant increases in sertraline and other antidepressant prescriptions suggest potential substitution of these medications for citalopram.