Open-Label placebo for the treatment of unipolar depression: Results from a randomized controlled trial

Abstract

Introduction The response to placebo is robust in studies of various antidepressant treatments. The strong placebo response, combined with the absence of side-effects, has prompted suggestions to use the ethically sound open-label placebo (OLP) as a treatment for depression. Objectives The aim of the present study was to assess the efficacy of OLP in the setting of a randomized controlled trial for the treatment of unipolar depression. Methods Thirty-eight patients (28 females, 73.7%) were randomized to either an eight-week treatment with OLP (n=18) or four week of treatment as usual (TAU) followed by four weeks of OLP (n=20). Clinical and socio-demographic measures were assessed at baseline, after four weeks, and at the end of the trial. Response to treatment was determined using the Quick Inventory of Depressive Symptomatology (QIDS SR-16). Results There was an overall decrease in depression levels over time, F(2,35) = 3.98, p = .028). A significant group x time interaction was found only among non-geriatric patients (<65y) with an early onset of depression (<50y), F(2,22) = 3.89, p = .036]. Post-hoc tests indicated a significant decrease during the first four weeks, but only in the OLP group, t(11) = 2.29, p = .043. Table 1: Demographic measures of OLP and TAU patients. Measures OLP (n = 18) TAU (n =20) Statistical analyses Age (years) [Mean ± SD] 48.17 ± 16.86 51.65 ± 17.68 t(36) = -0.62, p = .539 Education level (years) [Mean ± SD] 15.61 ± 3.66 14.22 ± 2.62 t(34) = 1.31, p = .200 Gender (male/female) [no.] 4 / 14 6 / 14 X2(1) = 0.30, p = .587 Age of onset (years) [Mean ± SD] 34.19 ± 15.82 32.45 ± 17.72 t(36) = 0.32, p= .752 Number of depressive episodes (no.) [Mean ± SD] 2.58 ± 2.61 6.64 ± 9.16 t(21) = -1.47, p = .156 Number of hospitalizations (no.) [Mean ± SD] 0.12 ± 0.33 0.17 ± 0.38 t(33)= -0.40, p = .689 Notes OLP = Open label placebo; SD = Standard deviation; TAU = Treatment as usual. Image 3: Conclusions Our findings support the possibility that OLP is an effective treatment for the relatively young population of patients suffering from depression. Additional studies are warranted in order to explore the use of open-label placebo in clinical work. Disclosure of Interest None Declared