DOLORisk: Research on Risk Factors and Determinants for Neuropathic Pain

Study Overview
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Brief Summary
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Patients with neuropathic pain of multiple etiologies and a control cohort of patients with the same neuropathic entities who did not develop neuropathic pain are examined clinically, phenotyped with QST and questionnaires. Both groups are analyzed in order to find risk factors for painful neuropathy.

Detailed Description
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Patients with probable (presence of a combination of symptoms and signs of neuropathy include any two or more of the following: neuropathic symptoms, decreased distal sensation, or unequivocally decreased or absent ankle reflexes) or confirmed (presence of an abnormality of NC or validated measure of small fiber neuropathy with class 1 evidence with corresponding symptoms) neuropathy are included. Patients are then further divided into those with painful and painless neuropathy according to the NeuPSIG algorithm. Patients with probable or definite neuropathic pain are classified as painful neuropathy, those with unlikely neuropathic pain classified as painless neuropathy (with concomitant nociceptive pain of other origin, e.g. headache etc.). Patients with possible neuropathic pain are excluded from analysis as are patients with skin lesions or dermatological disorders in the areas to be tested upon QST, with any painful or neurological comorbidity that could otherwise influence testing results such as vascular disease, radiculopathy, spinal canal stenosis etc. Inclusion was restricted to patients with polyneuropathy to make the investigated patient sample as homogenous as possible. Age, gender, BMI, ethnicity, years in education, family history of chronic pain, etiology of neuropathy, presence of early traumatic events and hospital admissions, smoking and alcohol habits, pain characteristics (von Korff, BPSI, NPSI), emotional well-being (PROMIS depression/ anxiety), personality (TIPI, IPIP, PCS), severity of neuropathy are assessed and QST performed.

Official Title
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The Influence of Sensory Phenotype on the Risk of Developing Neuropathic Pain

Conditions
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Neuropathic Pain

Intervention / Treatment
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* Diagnostic Test: Quantitative sensory testing (QST)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Diagnosis of Polyneuropathy Exclusion Criteria: Patients with polyneuropathy and possible neuropathic pain Patients with skin lesions or dermatological disorders in the areas to be tested upon QST Patients with any painful or neurological comorbidity that could otherwise influence testing results such as vascular disease, radiculopathy, spinal canal stenosis etc.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Painful neuropathy<br>Patients with presence of probable (presence of a combination of symptoms and signs of neuropathy include any two or more of the following: neuropathic symptoms, decreased distal sensation, or unequivocally decreased or absent ankle reflexes) or confirmed (presence of an abnormality of NC or validated measure of small fiber neuropathy with class 1 evidence with corresponding symptoms) neuropathy AND with probable or definite neuropathic pain according to the NeuPSIG algorithm. | Diagnostic Test: Quantitative sensory testing (QST)<br>* Demographic data, pain characteristics, health status, emotional well-being, personality and lifestyle are assessed by questionnaires. Additionally, all patients underwent a clinical neurological examination and quantitative sensory testing (QST) according to the German Research Network on Neuropathic Pain (DFNS).<br>* Other names: Different Questionnaires;|
| Painless neuropathy<br>Patients with presence of probable (presence of a combination of symptoms and signs of neuropathy include any two or more of the following: neuropathic symptoms, decreased distal sensation, or unequivocally decreased or absent ankle reflexes) or confirmed (presence of an abnormality of NC or validated measure of small fiber neuropathy with class 1 evidence with corresponding symptoms) neuropathy AND with unlikely neuropathic pain according to the NeuPSIG algorithm. | Diagnostic Test: Quantitative sensory testing (QST)<br>* Demographic data, pain characteristics, health status, emotional well-being, personality and lifestyle are assessed by questionnaires. Additionally, all patients underwent a clinical neurological examination and quantitative sensory testing (QST) according to the German Research Network on Neuropathic Pain (DFNS).<br>* Other names: Different Questionnaires;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Presence of Pain measured by Pain severity | Measurement on NRS [NRS 0-10] | through study completion, an average of 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Severity of Neuropathy measured by Toronto Neuropathy scale | Total Score [0-19 points] from history and clinical examination | through study completion, an average of 2 years | 
| Somatosensory phenotype measured by Quantitative sensory testing | Assessment of somatosensory phenotype with the protocol of the German REsearch Network of Neuropathic Pain (DFNS) | through study completion, an average of 2 years | 
| Emotional well-being | assessed by anxiety PROMIS Short Form v1.0 -Anxiety 6a, Depression 6a, Fatigue and Sleep | through study completion, an average of 2 years | 
| Personality characteristics | assessed by Ten-Item Personality Inventory and International Personality Item Pool's | through study completion, an average of 2 years | 
| Pain Catastrophizing | assessed by Pain Catastrophizing scale (PCS) total score [0-52 points] | through study completion, an average of 2 years | 
| Presence of family history of chronic pain | Presence of pain in family | through study completion, an average of 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pain prevention, painful neuropathy,, painless neuropathy, QST, patient-reported outcomes, PRO