Investigate the Relationship Between Catastrophizing and the Perception of Itch Intensity in Healthy Individuals

Investigation of the Neurophysiological and Psychological Aspects of Itch

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.

Study Overview

• Status: Recruiting
• Conditions: Histamine; Cowhage
• Intervention / Treatment: Other: Cowhage; Other: Histamine

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.

• Study Type: Interventional
• Enrollment (Estimated): 46
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Silvia Lo Vecchio, PhD; Phone Number: +4521397785; Email: slv@hst.aau.dk
• Study Contact Backup: Name: Giulia Erica Aliotta, PhD; Phone Number: 50290580; Email: gea@hst.aau.dk

Study Locations

• Denmark
  • Aalborg, Denmark, 9620
    • Recruiting
    • Aalborg University
    • Contact: Silvia Lo Vecchio, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

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)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Histamine application; In the first session, the subjects will fill some questionnaires. After that, a squared area of 4x4 cm will be selected at the center of each middle forearm of the subject and cowage or histamine will be applied for 10 minutes, during which the pain/itch following the cowhage/histamine application will be monitored with a VAS scale. After the itch-induction, the subjects will fill in other questionnaire. In second session, the subjects will fill some questionnaires. After that, a squared area of 4x4 cm will be selected at the center of each middle forearm of the subject and cowage or histamine will be applied for 10 minutes, during which the pain/itch following the cowhage/histamine application will be monitored with a VAS scale. After the itch-induction, the subjects will fill out other questionnaires. The order will be randomized, so if the subjects were given the cowhage in the first session, they will receive the histamine application in the second session, and vice versa.	Other: Histamine; Histaminergic itch will be evoked by a 1% histamine solution. A droplet of histamine solution will be placed on the predetermined area on the forearm, and the SPT lancet will be pierced through the histamine with 120 g of pressure for 1-2 seconds.
Other: Cowhage application; In the first session, the subjects will fill some questionnaires. After that, a squared area of 4x4 cm will be selected at the center of each middle forearm of the subject and cowage or histamine will be applied for 10 minutes, during which the pain/itch following the cowhage/histamine application will be monitored with a VAS scale. After the itch-induction, the subjects will fill in other questionnaire. In second session, the subjects will fill some questionnaires. After that, a squared area of 4x4 cm will be selected at the center of each middle forearm of the subject and cowage or histamine will be applied for 10 minutes, during which the pain/itch following the cowhage/histamine application will be monitored with a VAS scale. After the itch-induction, the subjects will fill out other questionnaires. The order will be randomized, so if the subjects were given the cowhage in the first session, they will receive the histamine application in the second session, and vice versa.	Other: Cowhage; 25 spicules will be inserted in the center of the predefined skin area on the mandibular area. The spicules will be gently rubbed for 15-20 seconds in circular motion to facilitate epidermal penetration.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Reinforcement Sensitivity Theory - Personality Questionnaire (RST-PQ).	The Reinforcement Sensitivity Theory - Personality Questionnaire contains the following subscales: the Fight-Flight-Freeze System (FFFS, 10 items); the Behavioral Inhibition System (BIS, 23 items); and the Behavioral Approach System (BAS, 32 items). In total, 65 items have to be answered on a 4-point Likert-type scale ranging from 1 (not at all) to 4 (Highly).	Baseline 1st session
The Pittsburg Sleep Quality Index (PSQI)	The PSQI consists of 19 items generating seven component scores: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction. The seven component scores can be summarized in a global score ranging from zero to 21 with higher scores reflecting a worse overall quality of sleep.	Baseline 1st session
Depression, Anxiety, Stress Scale (DASS-21)	The questionnaire measures the magnitude of depression, anxiety, and stress. Each of these three subscales consists of 7 questions answered using a 0-3 Likert scale, with 0 meaning "it did not apply to me", and 3 meaning "it applied to me very much"	Baseline 1st session
Positive And Negative Affect Schedule (PANAS)	PANAS measures positive and negative affect dimensions. Positive affects (PA) are defined as "the extent to which a person feels active, enthusiastic, and alert". Negative affect (NA) is a condition of "general distress and unpleasable engagement".	Baseline 1st session
Pain Catastrophizing Scale (PCS).	The PCS assesses negative and exaggerated coping concerning anticipated or experienced painful stimuli. Thirteen items have to be answered on a 5-point Likert-type scale ranging from 0 (Not at all) to 4 (all the time).	10 minutes after every itch induction on 1st session
Itch Catastrophizing Scale (ICS).	The ICS assesses negative and exaggerated coping concerning anticipated or experienced itchy stimuli. Thirteen items have to be answered on a 5-point Likert-type scale ranging from 0 (Not at all) to 4 (all the time).	10 minutes after every itch induction on 1st session
Learned Helplessness Scale (LHS)	The questionnaire consists of 20 items, and the participant's response to each item is rated on a 4-point Likert scale ranging from strongly agree (1) to strongly disagree (4).	10 minutes after every itch induction on 1st session
Positive And Negative Affect Schedule (PANAS)	PANAS measures positive and negative affect dimensions. Positive affects (PA) are defined as "the extent to which a person feels active, enthusiastic, and alert". Negative affect (NA) is a condition of "general distress and unpleasable engagement".	10 minutes after every itch induction on 1st session
Depression, Anxiety, Stress Scale (DASS-21)	The questionnaire measures the magnitude of depression, anxiety, and stress. Each of these three subscales consists of 7 questions answered using a 0-3 Likert scale, with 0 meaning "it did not apply to me", and 3 meaning "it applied to me very much"	Baseline 2nd session (3 days after 1st session)
Positive And Negative Affect Schedule (PANAS)	PANAS measures positive and negative affect dimensions. Positive affects (PA) are defined as "the extent to which a person feels active, enthusiastic, and alert". Negative affect (NA) is a condition of "general distress and unpleasable engagement"	Baseline 2nd session (3 days after 1st session)
Pain Catastrophizing Scale (PCS).	The PCS assesses negative and exaggerated coping concerning anticipated or experienced painful stimuli. Thirteen items have to be answered on a 5-point Likert-type scale.	10 minutes after every itch induction on 2nd session (3 days after 1st session)
Itch Catastrophizing Scale (ICS).	The ICS assesses negative and exaggerated coping concerning anticipated or experienced itchy stimuli. Thirteen items have to be answered on a 5-point Likert-type scale.	10 minutes after every itch induction on 2nd session (3 days after 1st session)
Learned Helplessness Scale (LHS)	The questionnaire consists of 20 items, and the participant's response to each item is rated on a 4-point Likert scale ranging from strongly agree (1) to strongly disagree (4).	10 minutes after every itch induction on 2nd session (3 days after 1st session)
Positive And Negative Affect Schedule (PANAS)	PANAS measures positive and negative affect dimensions. Positive affects (PA) are defined as "the extent to which a person feels active, enthusiastic, and alert". Negative affect (NA) is a condition of "general distress and unpleasable engagement"	10 minutes after every itch induction on 2nd session (3 days after 1st session)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessment of itch	Immediately following the itch provocations, participants will be instructed to rate the itch intensity for 10 minutes using a digital visual analogue scale (VAS; eVAS Software: Aalborg, University, Denmark), on a tablet. The scale will be measured from 0 to 100, where 0 represents 'no itch' and 100 'worst itch imaginable'.	1 minute after every itch inductions
Assessment of pain	Immediately following the itch provocations, participants will be instructed to rate the pain intensity for 10 minutes using a digital visual analogue scale (VAS; eVAS Software: Aalborg, University, Denmark), on a tablet. The scale will be measured from 0 to 100, where 0 represents 'no pain' and 100 'worst pain imaginable'.	1 minute after every itch inductions

Collaborators and Investigators

• Sponsor: Aalborg University

Study record dates

Study Major Dates

• Study Start (Actual): April 27, 2024
• Primary Completion (Estimated): December 31, 2025
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: March 19, 2024
• First Submitted That Met QC Criteria: March 28, 2024
• First Posted (Actual): April 1, 2024

Study Record Updates

• Last Update Posted (Actual): June 24, 2024
• Last Update Submitted That Met QC Criteria: June 19, 2024
• Last Verified: June 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Histamine Agents; Histamine Agonists; Histamine
• Other Study ID Numbers: N-20240004 3rd subproject

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No