Do children and adolescents have differential response rates in placebo-controlled trials of fluoxetine?

CNS Spectr. 2007 Feb;12(2):147-54. doi: 10.1017/s1092852900020666.

Abstract

Objective: Recent acute efficacy trials of antidepressants in youth have suggested that high placebo-response rates in children (< 12 years of age) indicate that children may be more responsive to non-specific treatment interventions. Yet, these studies generally have not presented age-specific outcome data. The objective of this study was to compare the efficacy outcomes for children (< 12 years of age) and adolescents (> or = 12 years of age) using the combined data from two previously published double-blind, placebo-controlled trials of fluoxetine.

Methods: Children (< 12 years of age) and adolescents (> or = 12 years of age) with major depressive disorder were randomized to fluoxetine or placebo for 8-9 weeks of treatment. Outcome was assessed using the Children's Depression Rating Scale-Revised (CDRS-R) and Clinical Global Impressions scale.

Results: Random regression of the CDRS-R showed a treatment group by age group interaction (F(1,338)=4.10, P=.044), indicating that the treatment effect was significantly more pronounced in children than adolescents. Within children, response at exit to fluoxetine was significantly better than placebo (56.9% vs 33.3%; P=.009). Adolescent response rates at exit were not significantly different between the groups (51.1% vs 38.6%; P=.128). Remission rates were low for both groups.

Conclusion: In the combined fluoxetine trials, drug-placebo difference was greater in children compared with adolescents. Contrary to expectations, the placebo-response rate was lower in the children than the adolescents.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Age Factors
  • Antidepressive Agents, Second-Generation / therapeutic use*
  • Child
  • Depressive Disorder, Major / diagnosis
  • Depressive Disorder, Major / drug therapy*
  • Depressive Disorder, Major / psychology
  • Double-Blind Method
  • Female
  • Fluoxetine / therapeutic use*
  • Follow-Up Studies
  • Humans
  • Male
  • Multicenter Studies as Topic
  • Personality Assessment
  • Randomized Controlled Trials as Topic
  • Treatment Outcome

Substances

  • Antidepressive Agents, Second-Generation
  • Fluoxetine