Genetic Variants and Postoperative Pain

Study Overview
=================
Brief Summary
-----------------
Prospective observational study to analyse patients' pain related outcome after surgery and ist association to genetic variants and non-genetic variables.

Detailed Description
-----------------
Background Severe acute pain as well as long-lasting pain after surgery and pain-related interference of daily activities are frequent. Some risk factors for severe pain after surgery in adults have been described, e.g. younger age and pre-existing chronic pain. The question arises whether a specific genetic background is related to an unfavorable pain outcome. Objective The aim of this study is to investigate clinical and genetic variables and their possible association to severe acute postoperative pain, higher analgesic consumption and the development of chronic postsurgical pain. Methods Prospective observational study investigating clinical, patient related, surgery related and anesthesia related variables as well as genetic variants and their possible association to patients' pain related outcome after surgery.

Official Title
-----------------
Genetic Variants and Postoperative Pain

Conditions
-----------------
Postoperative Pain, Analgesia, Surgical Procedure, Operative

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: 18 years and older Written informed consent Elective surgery Patients' ability to understand the purpose of the study Exclusion Criteria No informed consent Cognitive impairment

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| All patients<br>Patients undergoing elective surgery with anesthesia | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain related impairment after surgery and its association to genetic and non-genetic variables | Measured by the International Pain Outcomes Questionnaire, the Brief Pain Inventory (BPI): Numeric rating scale for pain intensities, affective and physical interference; Composite score = pain interference total scores (PITS scale 0-10) resulting in no interference (PITS=0), mild interference (PITS >0 and <2), moderate interference (PITS 2-5) and severe interference (PITS >5) | day of surgery up to 1 year after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association of genetic and non-genetic variables with analgesic consumption | analgesic consumption | day of surgery up to one year after surgery | 
| Association of genetic and non-genetic variables with pain related outcome of patients 1 year after surgery | Measured by the Brief Pain Inventory (BPI) as pain interference total score PITS scale 0-10) resulting in no interference (PITS=0), mild interference (PITS >0 and <2), moderate interference (PITS 2-5) and severe interference (PITS >5). Change of pain related impairment over time (before surgery, 2 days after surgery, 6 and 12 months after surgery) | Up to one year after surgery | 
| Association of genetic and non-genetic variables with chronic neuropathic postsurgical pain | Measured by a neuropathic pain questionnaire (number of neuropathic symptoms; at least three neuropathic symptoms are categorized as positive) | up to one year after surgery | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
postoperative pain, analgesics, patient reported outcome, pain related impairment, genetic association study