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

Aalborg University

Status: Enrolling

Conditions: Cowhage; Histamine

Treatments: Other: Histamine; Other: Cowhage

Study type: Interventional

Funder types: Other

Identifiers

NCT06340438

N-20240004 3rd subproject

Details and patient eligibility

About

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.

Full 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.

Enrollment: 46 estimated patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

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)

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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46 participants in 2 patient groups

Histamine application

Other group

Description:

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.

Treatment:

Other: Histamine

Cowhage application

Other group

Description:

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.

Treatment:

Other: Cowhage