A power analysis for future clinical trials on the potential adverse effects of SSRIs on amygdala reactivity

Abstract

Treatment of adolescents with antidepressants may induce an increased risk for suicidality in this population. The activity of the amygdala during processing of emotional faces with functional Magnetic Resonance Imaging (fMRI) is a well-known measure of emotional dysregulation. Based upon data of our prematurely ended randomized clinical trial with fluoxetine (NTR3103) in anxious and or depressed girls (12–14 years of age) we calculated that with the found effect size of r = 0.66, compared to placebo, only 8 subjects are needed to demonstrate increased amygdala activity following 16 weeks of treatment with fluoxetine.

Keywords

amygdala reactivity / SSRI / adverse effects / anxiety / depression

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Acknowledgments

We thank Dr. Anne Klomp for her work in setting up this RCT. This work was sponsored by personalized funding obtained by the Netherlands Organisation for Health Research and Development (Veni grant nr. 91686125 awarded to Liesbeth Reneman).

Compliance with ethics guidelines

Marco Bottelier declares that he received research funding from a private fund Suffugium. Anouk Schrantee, Guido van Wingen, Eric Ruhe, Michiel de Ruiter and Liesbeth Reneman declare that they have no conflict of interest.

All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000 (5). Informed consent was obtained from all patients for being included in the study.

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2016 Higher Education Press and Springer-Verlag Berlin Heidelberg