Abstract
Objective: Several ADHD pharmacological trials reported high placebo response (PR) rates. This study aims to characterize the PR in adult ADHD. Method: A retrospective cohort analysis of the placebo arm (140 adults with ADHD, 18-55 yrs, M:F 46.4%-53.6%) of a 6-week randomized, multicenter, double-blind metadoxine study, using Conners’ Adult ADHD Rating Scale (CAARS) and the Adult ADHD Self-Report Scale (ASRS), was conducted. Results: Pre–post changes in placebo-treated adults were significant for both the CAARS and ASRS, F(2.9, 404.5) = 61.2, p <.00001, F(2.8, 383.0) = 43.1, p <.00001, respectively. Less than half of the participants had a PR which began early in treatment and persisted; almost 50% had a variable, inconsistent PR. Conclusion: In the current sample, PR in adult ADHD was prominent on both symptom scales and the investigator–rater instrument. Therefore, using investigator ratings as a primary endpoint does not necessarily attenuate PR. Of note, about half of the PR is variable, suggesting unreliable determination of efficacy.
| Original language | English |
|---|---|
| Pages (from-to) | 425-433 |
| Number of pages | 9 |
| Journal | Journal of Attention Disorders |
| Volume | 24 |
| Issue number | 3 |
| DOIs | |
| State | Published - 1 Feb 2020 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© The Author(s) 2018.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Drs. Ben-Sheetrit, Newcorn, Danieli, Weizman, Peskin and Manor participated in a series of studies funded by Alcobra Ltd.
| Funders | Funder number |
|---|---|
| Alcobra Ltd. |
Keywords
- adult ADHD
- nocebo
- nonstimulants
- placebo