Clinical trial NCT06340438: Investigate the Relationship Between Catastrophizing and the Perception of Itch Intensity in Healthy Individuals
Official title: Investigation of the Neurophysiological and Psychological Aspects of Itch
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Histamine
Cowhage
Lead sponsor: Aalborg University
Sponsor class: OTHER
First posted: 2024-04-01
Enrollment: 46
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: The participants will randomly receive applications of cowhage and histamine.
Primary purpose: BASIC_SCIENCE

Brief summary: This project aims to investigate the relationship between different dimensions of catastrophizing (rumination, magnification, and helplessness) as well as some specific personality traits related to catastrophizing tendencies like anxiety sensitivity and fear sensitivity in the modulation of itch and pain intensities in an experimental setting.

Detailed description: Chronic itch severely affects the quality of life of patients by interfering with vital functions such as sleep, attention, and sexual activity, with an elevated expression of cognitive and emotional factors such as itch catastrophizing, worrying, as well as personality characteristics such as the predisposition to anxiety, depression, and suicidal thoughts that play an important role in the development, modification, and maintenance of itch. Moreover, chronic itch represents a significant socioeconomic burden due to a prevalence of around 10% in combination with largely suboptimal treatment since limited evidence has been found for the effectiveness of pharmaceutical interventions. The hypothesis of this project is that since it is well documented that the relationship between catastrophizing and pain and that itch and pain share many similarities, investigators can assume the existence of a similar connection between catastrophizing and itching.

Eligibility criteria: Inclusion Criteria:

* Healthy men and women
* 18-60 years
* Speak and understand English

Exclusion Criteria:

* Pregnancy or lactation
* Drug addiction defined as any use of cannabis, opioids, or other addictive drugs
* Previous or current history of neurological (e.g. neuropathy), immunological (e.g. asthma, immune deficiencies, arthritis), musculoskeletal (e.g. muscular pain in the upper extremities,), cardiac disorder, or mental illnesses that may affect the results
* Lack of ability to cooperate
* Current use of medications that may affect the trial such as antihistamines, antipsychotics, and pain killers, as well as systemic or topical steroids
* Skin diseases (e.g. atopic dermatitis, pruritus nodularis, eczema, psoriasis)
* Moles, scars, or tattoos in the area to be treated or tested.
* Consumption of alcohol or painkillers 24 hours before the study days and between these
* Acute or chronic pain
* Participation in other trials within one week of study entry (four weeks in the case of pharmaceutical trials)

Primary outcomes:
measure: Reinforcement Sensitivity Theory - Personality Questionnaire (RST-PQ).
timeFrame: Baseline 1st session
measure: The Pittsburg Sleep Quality Index (PSQI)
timeFrame: Baseline 1st session
measure: Depression, Anxiety, Stress Scale (DASS-21)
timeFrame: Baseline 1st session
measure: Positive And Negative Affect Schedule (PANAS)
timeFrame: Baseline 1st session
measure: Pain Catastrophizing Scale (PCS).
timeFrame: 10 minutes after every itch induction on 1st session
measure: Itch Catastrophizing Scale (ICS).
timeFrame: 10 minutes after every itch induction on 1st session
measure: Learned Helplessness Scale (LHS)
timeFrame: 10 minutes after every itch induction on 1st session
measure: Positive And Negative Affect Schedule (PANAS)
timeFrame: 10 minutes after every itch induction on 1st session
measure: Depression, Anxiety, Stress Scale (DASS-21)
timeFrame: Baseline 2nd session (3 days after 1st session)
measure: Positive And Negative Affect Schedule (PANAS)
timeFrame: Baseline 2nd session (3 days after 1st session)
measure: Pain Catastrophizing Scale (PCS).
timeFrame: 10 minutes after every itch induction on 2nd session (3 days after 1st session)
measure: Itch Catastrophizing Scale (ICS).
timeFrame: 10 minutes after every itch induction on 2nd session (3 days after 1st session)
measure: Learned Helplessness Scale (LHS)
timeFrame: 10 minutes after every itch induction on 2nd session (3 days after 1st session)
measure: Positive And Negative Affect Schedule (PANAS)
timeFrame: 10 minutes after every itch induction on 2nd session (3 days after 1st session)
Secondary outcomes:
measure: Assessment of itch
timeFrame: 1 minute after every itch inductions
measure: Assessment of pain
timeFrame: 1 minute after every itch inductions
Other outcomes:
Locations:
city: Aalborg
country: Denmark
facility: Aalborg University
Study officials:
References: