Pain Sensitivity in Acute Inflammatory Pain

Study Overview
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Brief Summary
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Pain is a complex experience influenced by gender and genetics, and, by psychosocial and sensory experiences. Pain sensitivity is thus highly variable between individuals. In the present study we evaluate individuals´ pain perception in response to a number of different pain stimuli in 100 healthy volunteers (50 females and 50 males). The data will allow us to assess pain sensitivity, to predict pain responses and to investigate gender related differences in pain perception. A second aim is to evaluate the robustness of the different pain-tests since the tests are repeated with an interval of 2-4 weeks.

Detailed Description
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Pain perception is affected by physiological, psychological, existential and demographic factors. In the present study psychophysiological, psychological, genetic and demographic components in pain perception are evaluated in healthy volunteers (n = 100). Psychophysical assessments following induction of a first degree burn injury (47.0 C, 420 s, 12.5 sq.cm, lower leg) include: pain during induction of burn injury thermal thresholds tactile thresholds electrical thresholds areas of secondary hyperalgesia pressure algometric assessments assessment of Diffuse Noxious Inhibitory Control (DNIC) efficiency assessment of (DNIC) using cold pressor test Psychological assessments include: HADS (Hospital Anxiety and Depression Scale) PCS (Pain Catastrophizing Scale) vulnerability score Genetics include: - A118G SNP Demographics include: gender height weight

Official Title
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Pain Sensitivity in Acute Inflammatory Pain - Gender Differences and Validity of Sensory Tests

Conditions
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Healthy Volunteers Are Studied

Intervention / Treatment
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* Procedure: first degree cutaneous burn injury


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy psychomotor ability to perform the tests cognitive ability to perform the tests Exclusion Criteria: smoker Body Mass Index > 28 participation in drug studies < 4 weeks prior to inclusion chronic pain chronic intake of analgesics drug or alcohol abuse intake of analgesics < 48 hours prior to study females not on contraceptive therapy (intra-uterine device or p-pill) lesion in the assessment area

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: gender<br> | Procedure: first degree cutaneous burn injury<br>* application of thermode (5 x 2.5 cm) to lower leg temperature 47.0 C, 420 s<br>* Other names: Modular Sensory Analyzer Thermotest (Somedic, Hörby, Sweden);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| pain following burn injury |  | from baseline to 420 s after burn injury | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| thermal thresholds |  | followed for 180 min after burn injury | 
| tactile thresholds |  | followed for 180 min after burn injury | 
| pressure algometry assessments |  | 95 min prior to burn injury | 
| DNIC-efficiency |  | 45 min before burn injury | 
| cold pressor test |  | 85 min before burn injury | 
| HADS score |  | 2 hours before the burn injury | 
| PCS ratings |  | 2 hours before the burn injury | 
| A118G SNP |  | 8 months after inclusion completed | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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burn injury, cold pressor test, gender, pain, pain sensitivity, pain prediction, psychometrics, quantitative sensory testing