Moderation of antidepressant and placebo outcomes by baseline severity in late-life depression: A systematic review and meta-analysis.
BACKGROUND
Baseline severity is a crucial moderator of trial outcomes in adult depression, with the advantage of antidepressants over placebo increasing as severity increases. However, this relationship has not been examined in late-life depression.


METHODS
PubMed, Embase, Web of Science, PsycINFO, and Cochrane were searched for studies published through September 2014. Randomized, acute phase, and double-blind studies comparing an antidepressant group with a placebo group in depressed elderly patients were included.


RESULTS
Nineteen studies met all inclusion criteria. Within-group effect sizes revealed significant improvement in antidepressant groups (g=1.35, p<.000), as well as in placebo groups (g=.96, p<.000). Change in depressive symptoms assessed by Hamilton Depression Rating Scale (HDRS) was moderated by baseline severity in antidepressant groups (Z=2.67, p=.008) and placebo groups (Z=4.46, p<.000). However, this would be expected as a result of regression toward the mean, and mean differences between groups did not increase (r=.19, p=.469) as a function of baseline severity.


CONCLUSIONS
Limited to published data and information was only analyzed at the level of treatment groups.


CONCLUSIONS
Baseline severity was not associated with an antidepressant-placebo difference and placebo responses are large in the treatment of depressed elderly people. We propose a stepwise approach, i.e., to initially offer elderly depressed patients psychosocial interventions and only consider antidepressants if patients do not respond.
Department of Clinical Psychology and Psychotherapy, University of Basel, Basel, Switzerland. Electronic address: cosima.locher@unibas.ch.
Cosima
C
Locher
Department of Clinical Psychology and Psychotherapy, University of Basel, Basel, Switzerland; Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, USA; Program in Placebo Studies and the Therapeutic Encounter, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA.
Joe
J
Kossowsky
Department of Clinical Psychology and Psychotherapy, University of Basel, Basel, Switzerland.
Jens
J
Gaab
Program in Placebo Studies and the Therapeutic Encounter, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA.
Irving
I
Kirsch
Countway Library of Medicine, Harvard Medical School, Boston, USA.
Paul
P
Bain
Department of Clinical Psychology and Psychotherapy, University of Basel, Basel, Switzerland; Collegium Helveticum, University of Zurich and ETH Zurich, Zurich, Switzerland.
Peter
P
Krummenacher
D000928:Antidepressive Agents / Q000627:therapeutic use*; D003863:Depression / Q000188:drug therapy*; D004311:Double-Blind Method; D006801:Humans; D000067562:Late Onset Disorders / Q000188:drug therapy*; D015990:Placebo Effect; D012720:Severity of Illness Index
D000928:Antidepressive Agents
Antidepressants; Baseline Severity; Depression; Elderly; Meta-analysis; Placebo