13-year Follow-up of Women With Chronic Low Back Pain in Primary Care - a Prospective Longitudinal Cohort Study

Study Overview
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Brief Summary
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Background: Low back pain (LBP) is among the main causes of long-term sickness absence and is associated with considerable costs for both the individual and society. LBP affects 60-80% of the population and most individuals recover, while about 10-20% develop persistent pain and disability. Women have a higher risk of developing chronic LBP (CLBP) and widespread pain. Purpose: To investigate change in body function, activity, participation and other health related factors in women with CLBP after 13 years and to identify prognostic factors for pain, activity limitation and work ability. Methods: In the present study, all women (n = 131) who were included in the cross-sectional study in 2006 and who were followed-up after 2 years are now invited to the same study-protocol 13 years after the first examination in 2006. The Swedish Ethical Review Authority approved the study. Dnr: 2019-01944, 2019-05-21.

Detailed Description
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Background: Low back pain (LBP) is among the main causes of long-term sickness absence and is associated with considerable costs for both the individual and society. LBP affects 60-80% of the population and most individuals recover, while about 10-20% develop persistent pain and disability. Women have a higher risk of developing chronic LBP (CLBP) and widespread pain. How LBP develops into recurrent and or more persistent pain with disability is not fully understood. Prognostic factors for pain development, work ability and self-rated activity limitation in 1 and 2-year follow-ups of persons with CLBP who sought primary care are described. Performance on physical capacity tests (6-min walking test), limitations on self-rated activity and participation and psycho-social factors play a role in unfavorable pain and function development. However, there are patients with CLBP who have no anatomical, demographic or psychosocial explanation of their symptoms. Some people with CLBP also have widespread pain and show altered pain sensitivity as fibromyalgia. Purpose:To investigate change in body function, activity, participation and other health related factors in women with CLBP after 13 years and to identify prognostic factors for pain, activity limitation and work ability. Methods: In the present study, all women (n = 131) who were included in the cross-sectional study in 2006 and who were followed-up after 2 years are now invited to the same study-protocol 13 years after the first examination in 2006. Participants will be assessed by a registered physiotherapist at one occasion. Demographic data are collected, Questions about social support, sleep quality and sleep quantity, smoking and alcohol consumption. Self-reported questionnaires, pain and function performance tests will be assessed. Data Analysis: Descriptive analysis based on data level; mean value (standard deviation), median (25th; 75th percentile), number and proportion will be used to present the group's characteristics. For analysis of change between the first assessment and after 13 years, Wilcoxon's signed rank test will be used for continuous variables and Teckentest / McNemar's test will be used for nominal data. Multivariable regression analysis will be performed to calculate predictors of pain intensity (VAS), number of pain locations/pain distribution, self-rated activity limitation (RMDQ) and work ability after 13 years. Independent variables will be variables at the first assessment within the domains; body function (pain intensity, pain distribution, pain sensitivity, anxiety, depression, function test and stress), activity (RMDQ) and participation (work ability), as well as other health-related factors (Health-Related Quality of Life (SF-36), Leisure Time Physical Activity Instrument, Experience of Physical Activity). Multivariable regression models will be adjusted for age, level of education and social status. P-value is set to 0.05. Ethical approval: The Swedish Ethical Review Authority approved the study. Dnr: 2019-01944, 2019-05-21. Expected Results: The results is expected to provide knowledge about long-term clinical course (13 years) and prognostic factors for a positive pain and function development of CLBP in women seeking primary care.

Official Title
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13-year Follow-up of Women With Chronic Low Back Pain in Primary Care - a Prospective Longitudinal Cohort Study

Conditions
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Low Back Pain, Chronic Widespread Pain, Predictors, Pain, Physical Activity, Work Ability

Intervention / Treatment
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* Other: Change in function, activity, participation and other health related factors in CLBP and to identify predictors for pain, activity and work ability after 13 years.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All participants (n=131) included in the Cross Sectional Study in 2006 Exclusion Criteria: Pregnant Serious somatic disorders Serious psychiatric disorders

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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Female

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 |
| --- | --- |
| 131 participants with chronic low back pain<br>All the participants (n=131) with chronic low back pain (CLBP) from the cross-sectional study in 2006 are invited to participate in the present 13-year follow-up. The same examination battery used in the cross-sectional study plus a supplementary Chair Stand Test will be used. | Other: Change in function, activity, participation and other health related factors in CLBP and to identify predictors for pain, activity and work ability after 13 years.<br>* 13-year prospective longitudinal cohort study<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Activity limitation | Roland and Morris Disability Questionnaire (RMDQ) will be used. | 2019, change from the first assessment (2006) to the present 13-year follow-up (2019), identify predictors (2006) for activity limitation (RMDQ) at the 13-year follow-up | 
| Pain intensity | A Visual Analogue Scale (VAS), ranging 0 to 100 mm will be used for pain intensity during the last week. 0 mm indicates no pain and 100 mm indicates very severe pain. Higher score indicates more severe pain. | 2019, Change from the first assessment (2006) to the present 13-year follow-up (2019), identify predictors (2006) for pain intensity (VAS) at the 13-year follow-up. | 
| Work ability | Sick-leave periods, and sickness and activity compensation is obtained from the Swedish Social Insurance Agency's MiDAS database. Self-reported work status dichotomized into two categories, work ability or not will be used. | 2019, Comparison from the first assessment (2006) to the present 13-year follow-up (2019), identify predictors (2006) for work ability at the 13-year follow-up. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain distribution | A drawing of the body will be used for assessing distribution of pain | 2019, Comparison from the first assessment (2006) to the present 13-year follow-up (2019), identify predictors (2006) for pain distribution at the 13-year follow-up. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Low Back Pain, Pain, Physical Activity, Physical Capacity, Work Ability, Primary Health Care