The role of nocebo effects in identifying patients at risk for pain progression in fibromyalgia

Recruitment & Eligibility

Status: Completed

Sex: Not specified

Target Recruitment: 75

Inclusion Criteria

18-65 years old female
Good understanding of written and spoken Dutch
Additionally for Patients:
Diagnosis of fibromyalgia (provided by a rheumatologist)

Exclusion Criteria

For patients:
Physical conditions other than fibromyalgia explaining pain symptoms
Psychiatric conditions not related to fibromyalgia symptoms (e.g.,
schizophrenia)
Use of painkillers different than usual dose of treatment on the day of
experimentation*
For healthy controls:
Chronic pain complaints (>=3 months) in the past or present or a diagnosis of
fibromyalgia
Severe physical or psychiatric co-morbidities that may interfere with the study
protocol (e.g., DSM-V diagnosis)
Current pain (>=3/10 on the Numeric Rating Scale) on the day of experimentation*
Use of painkillers within 24 hours before the day of experimentation*
Common criteria for both groups:
Pregnancy or lactation
Color blindness
Injuries/open wounds on the non-dominant hand or arm*
Carrying a pacemaker/implanted pumps
Having implanted metals on the non-dominant hand or arm
Refusal to remove artificial nails, nail polish, or any other substance
covering the thumbnail*
Unsuccessful pressure calibration, i.e., not being able to stably distinguish
relevant pressure intensities
*Exclusion criteria marked with a * pertain to the day of testing. In case one
or more of these criteria are met at the day of testing, the appointment will
be rescheduled if possible.

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>In part 1, individual susceptibility to nocebo conditioning (pain levels in<br /><br>conditioned trials versus control trials) will be studied as predictor of the<br /><br>main follow-up parameter, i.e., changes in self-reported clinical pain from<br /><br>baseline to follow-up. In part 2, susceptibility to nocebo conditioning will be<br /><br>examined and compared between patients and healthy controls. In part 3,<br /><br>within-group stability in susceptibility to nocebo conditioning will be<br /><br>examined across 1 month. </p><br>

Secondary Outcome Measures

Name	Time	Method
<p>Secondary study parameter of part 1 include individual differences in<br /><br>susceptibility to extinction learning as secondary predictor of pain<br /><br>progression. We will also explore the relation of these predictors, i.e. nocebo<br /><br>conditioning and extinction, to secondary follow-up parameters of fibromyalgia<br /><br>progression and daily symptom fluctuations. In part 2, extinction learning will<br /><br>be examined and compared between patients and healthy controls, and in part 3<br /><br>within-group stability in extinction learning, and between-group comparisons of<br /><br>stability in nocebo-related learning processes (conditioning and extinction)<br /><br>will be examined across 1 month. </p><br>