The risk of antidepressant induced suicidal ideas in children and young adults has been a controversy since 2003. In 2004, FDA added this as a black box warning on all antidepressants. The meta analysis FDA used included studies that were not designed to examine these effects. Relative risk for suicidal behavior or ideation in this meta analysis was 1.95 (95% confidence interval 1.28 to 2.98) for young people treated with antidepressants compared with those given placebo. Suicide is the third leading cause of death in 15-24 age group and antidepressants are widely used to treat depression/ suicidal behaviours. Antidepressant use fell significantly following FDA findings.
Christine Y Lu et al investigated how the FDA recommendations changed the prescription of antidepressants as well as suicidal behaviours in 11 US health care organisations, who serves members who are generally representative of each system’s geographic service area . The percentage of enrollees who were dispensed an antidepressant was calculated for adolescents , young adults and adults. An interrupted time series analysis ( i.e. this method can control for secular trends whether the fad warnings caused abrupt changes in the level or the pre-existing trend of suicidal behaviours). The cohort had 1.1 million adolescents, 1.4 million young adults, and 5 million adults per quarter.
1. Adolescents: FDA warnings caused an abrupt decline in the previously upward trend of antidepressant use by adolescents. In the second year after warnings, relative reduction of 31.0% in antidepressant use was noted. This coincided with a relative increase of 22 % in psychotropic drug poisonings in the second year after the warnings. There were no differences in completed suicides.
2.Young adults: Similar to adolescents a relative reduction of 24 % in antidepressant use in the second year after the warnings was observed along with a relative increase of 34 % in psychotropic poisoning the second year after the warnings . Completed suicide rates remained stable.
3.Adults: Antidepressant use showed a relative reduction of 14.5% , this coincided with a statistically insignificant increase in psychotropic poisoning.
Results were consistent across different areas. Similar findings are reported by others before. The downward trend of antidepressant use stopped in 2008, possibly following 2007 modified recommendation ( i.e. asking prescribers to consider risk of not treating mood disorders) from FDA.
Limitations: Only third of suicidal attempts are medically treated and the data is of those who were treated. ( this could have under estimated the suicidal attempts). Psychotropic drug poisonings account for about 38% of suicide attempts, the results underestimate increases in suicide attempts after the warnings.
Conclusions: Restricted antidepressant use was associated with increased rather than decreased suicide attempts. Regulatory warnings may have unintended consequences. It is important to monitor population level effects of such warnings.
Summary of the article:
Lu CY, Zhang F, Lakoma MD, Madden JM, Rusinak D, Penfold RB, Simon G, Ahmedani BK, Clarke G, Hunkeler EM, Waitzfelder B, Owen-Smith A, Raebel MA, Rossom R, Coleman KJ, Copeland LA, Soumerai SB. BMJ. 2014 Jun 18;348:g3596.