Evidence map›Paper›PMID 37703397›Full record

Trial reportPain2024

Placebo analgesia and nocebo hyperalgesia in patients with Alzheimer disease and healthy participants.

Susan Tomczak Matthiesen, Mette Sieg, Stephanie Skøtt Andersen, Martina Amanzio, Nanna Brix Finnerup, Troels Staehelin Jensen, Hanne Gottrup, Lene Vase

Abstract readRandomized Controlled Trial
PubMed Publisher
In one paragraph

Trial report in Pain, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed, 1 pooled it
1.4field-weighted citation impact, top 19% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5 citing papers in PubMed, 1 synthesis or guideline pooled it, 8 citations in OpenAlex.

  1. Pooled it
  2. Trial
  3. Trial
  4. Mechanisms of comorbidity between Alzheimer's disease and pain.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2025
    Review
  5. Article
4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

8 authors at 3 institutions in 2 countries.

Susan Tomczak MatthiesenDivision for Psychology and Neuroscience, Department of Psychology and Behavioral Science, School of Business and Social Sciences, Aarhus University, Denmark.
Mette SiegDivision for Psychology and Neuroscience, Department of Psychology and Behavioral Science, School of Business and Social Sciences, Aarhus University, Denmark.
Stephanie Skøtt AndersenDivision for Psychology and Neuroscience, Department of Psychology and Behavioral Science, School of Business and Social Sciences, Aarhus University, Denmark.
Martina AmanzioDepartment of Psychology, University of Turin, Turin, Italy.
Nanna Brix FinnerupDepartment of Clinical Medicine, Danish Pain Research Center, Aarhus University, Denmark.
Troels Staehelin JensenDepartment of Clinical Medicine, Danish Pain Research Center, Aarhus University, Denmark.
Hanne GottrupDepartment of Neurology, Aarhus University Hospital, Aarhus, Denmark.
Lene VaseDivision for Psychology and Neuroscience, Department of Psychology and Behavioral Science, School of Business and Social Sciences, Aarhus University, Denmark.
Aarhus University · DKAarhus University Hospital · DKUniversity of Turin · IT

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

abstractThe role of placebo analgesia and nocebo hyperalgesia in patients with Alzheimer disease (AD) is largely unknown, with only few studies in the area. Therefore, this study aims to investigate to which extent placebo analgesia and nocebo hyperalgesia effects are present in patients experiencing mild-to-moderate AD. Twenty-one patients with AD (test population) and 26 healthy participants (HP; design validation) were exposed to thermal pain stimulation on 3 test days: Lidocaine condition (open/hidden lidocaine administration), capsaicin condition (open/hidden capsaicin administration), and natural history (no treatment), in a randomized, within-subject design. Open lidocaine and open capsaicin were accompanied by verbal suggestions for pain relief and pain increase, respectively. Expected pain and actual pain intensity were measured on a numerical rating scale (0-10). Placebo and nocebo effects were calculated as pain differences in open-hidden lidocaine and capsaicin, respectively, controlled for no treatment. Healthy participants obtained a placebo effect ( P = 0.01) and a trend for a nocebo effect ( P = 0.07). Patients with AD did not obtain a placebo effect ( P = 0.44) nor a significant nocebo effect ( P = 0.86). Healthy participants expected lower and higher pain with open vs hidden lidocaine and capsaicin, respectively ( P < 0.001). The same expectation effects were seen in patients with AD (open vs hidden lidocaine, P = 0.008; open vs hidden capsaicin, P < 0.001). With a well-controlled experimental setting, this study suggests that patients with AD may not experience placebo analgesia effects. Nocebo hyperalgesia effects in patients with AD needs further research. These findings may have implications for the conduction of clinical trials and the treatment of patients with AD in clinical practice.

Indexed as

Alzheimer DiseaseAnalgesiaCapsaicinHealthy VolunteersHumansHyperalgesiaLidocaineNocebo EffectPainPlacebo EffectCapsaicinLidocaine

Identifiers

PMID37703397
OpenAlexW4386698881

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.