Neuropathic Spinal Pain in Ankylosing Spondylitis

Study Overview
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Brief Summary
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The aim of this study is to investigate prevalence of neuropathic spinal pain in AS patients and it's impact on sleep quality. Moreover effects of neuropathic pain on quality of life and fatigue will be assessed.

Detailed Description
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Ankylosing spondylitis (AS) is a chronic, inflammatory rheumatic disease that mainly presenting with chronic back pain. In general, chronic low back pain is currently defined as a mixed pain including nociceptive and neuropathic properties. Nociceptive pain in several rheumatic diseases displays neuropathic characteristics over time. Patients with AS are suffered from spinal, entheseal pain or pain originated from peripheral and root joints. Although being scarce, there are trials investigating and reporting neuropathic component of spinal pain in axial spondyloarthritis/ankylosing spondylitis patients. However these trials either are not controlled or did not specify painful region of interest. In a few controlled trials control subjects were not defined clearly. Sleep problems are reported to be prevalent among patients with chronic pain conditions such as inflammatory rheumatic diseases and fibromyalgia. In patients with ankylosing spondylitis sleep disturbance is a well defined issue. The fact that sleep problem is a common problem in AS, raises the need to explore it's associates. In the trials measuring spinal neuropathic pain, sleep disturbances and it's association with neuropathic pain were not assessed. So, investigators have aimed to investigate prevalence of neuropathic spinal pain in AS patients and it's impact on sleep quality. For this purpose a case-control study design was planned. Age- and sex-matched control subjects will be chosen among individuals submitted to out-patient clinic with nociceptive/mechanical pain complaint lasting more than three months. Participants in control group will be subjected to same exclusion criteria too. This design will allow the investigators to determine whether spinal pain in AS patients displays neuropathic character more frequently than any chronic nociceptive pain does.

Official Title
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Prevalence of Spinal Neuropathic Pain in Ankylosing Spondylitis Patients and it's Impact on Sleep Quality: a Case-control Study

Conditions
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Ankylosing Spondylitis

Intervention / Treatment
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* Other: Questionnaires and inventories


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Being diagnosed with AS according to the 1984 Modified New York Criteria Visual Analogue Scale (VAS) spinal pain score ≥ 2 Exclusion Criteria: Diabetes mellitus, renal insufficiency, hypothyroidism Carpal tunnel syndrome, postherpetic neuralgia, spinal cord compression Neurological diseases leading to neuropathic pain Cervical and lumbar radiculopathy Fibromyalgia Malignancy Severe cardiac disease Pregnancy Muscle weakness or hypoesthesia indicating peripheral nerve injury In the last three months medical treatment leading to neuropathy (colchicine etc.) In the last three months drug use for the treatment of fibromyalgia, depression and anxiety

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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 |
| --- | --- |
| AS patients<br>AS patients diagnosed according to the modified New York criteria | Other: Questionnaires and inventories<br>* questionnaires and inventories related to primary end secondary outcomes will be applied and physical examination will be performed.<br>* Other names: physical examination;|
| Control<br>Age- and sex-matched control subjects with nociceptive/mechanical pain complaint lasting more than three months | Other: Questionnaires and inventories<br>* questionnaires and inventories related to primary end secondary outcomes will be applied and physical examination will be performed.<br>* Other names: physical examination;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neuropathic pain | It will be assessed using the PainDETECT questionnaire. This questionnaire contains nine questions all of which are self-report. Seven items are rated on a six point Likert scale and thus are scored between 0-5. These seven questions query some sensations such as burning, tingling or prickling, allodynia, numbness etc. Apart from these seven items, one item assesses the radiation of pain and the other one item looks for the temporal characteristics of pain. A total score of 12 or less indicates neuropathic component is unlikely, 13-18 means possible neuropathic component and 19 or greater means a neuropathic component is likely. Beside these, there are three items in a separate section measuring severity of pain at the time of evaluation, on average and maximum over the past month. This section is not taken into account in scoring | Once, at baseline | 
| Sleep quality | It will be assessed using Pittsburgh Sleep Quality Index (PSQI). It was developed by Buysse and coworkers in 1989. This index measures sleep quality quantitatively and covers 24 questions. Nineteen questions are self-rated and scoring is based on these self-rated questions, other five questions that rating by partner are not taken into account while calculating total score. Questionnaire measures seven domains; subjective sleep quality (question 6), sleep latency (question 2 and 5a), sleep duration (question 4), habitual sleep efficiency (question 1,3,4), sleep disturbances (question 5b-j), use of sleep medication (question 7), and daytime dysfunction (question 8 and 9) over the last month. Seven domain scores give a result on a 0 to 3 scale. To yield a total score the domain scores are summed. Total score varies between 0 and 21. Higher scores indicate worse sleep quality. | Once, at baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Health related quality of life | Health related quality of life will be assessed using (Ankylosing Spondylitis Quality of Life Questionnaire (ASQoL) querying symptoms, functioning, and disease-related concern. It covers 18 dichotomous questions that ask participants to answer in a yes or no fashion. An answer of yes is assumed as one point. To get a final score, all points are summed. Thus, total score is between 0-18 and higher scores indicate worse quality of life. | Once, at baseline | 
| Fatigue | It will be assessed using Fatigue Severity Scale. This scale contains nine questions and measures fatigue severity during the past week. Each question is rated between 1 (strongly disagree)-7 (strongly disagree). Total score is mean of all To calculate total score first the points of all answers are summed and then the result is divided by nine. Higher scores indicate severe fatigue | Once, at baseline |