Health and Risk Factors in Patients With Hip and Knee Osteoarthritis

Study Overview
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Brief Summary
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Hip and knee osteoarthritis is one of the leading causes of global disability. There is no cure for the disease, but research and guidelines recommends that patients with osteoarthritis, early after the diagnosis, receive individually adapted physical exercises, information about their disease and about self-management and, if needed, recommendations on weight loss as a core treatment to prevent disability and impairment in health. This core treatment improves symptoms in osteoarthritis by reducing pain and increasing function, and have the potential to delay replacement surgery. In Sweden, core treatment has since 2008, been standardized in a supported self-management programme and evaluation and follow-ups are registered in the National Quality Register BOA (Better management of patients with OsteoArthritis). The course of deterioration in pain and physical functioning among different individuals with osteoarthritis is currently difficult to predict. Factors such as socioeconomic status and comorbidity contribute to progression of the disease, but are not fully established. There is a need for early identification of individuals who have a good prognosis with slow disease development and those that should be recommended joint replacement surgery in the future. Overriding aim of the study is to increase knowledge about the population who has received education and supervised exercises as a core treatment for hip and knee osteoarthritis and been registered in the BOA Register and to identify factors that can predict long-term outcome for this population.

Detailed Description
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Study design: This is a nationwide observational cohort study using prospectively obtained individual-level register data from five main sources; the BOA Register, the Swedish Hip Arthroplasty Register (SHAR), the Swedish Knee Arthroplasty Register (SKAR), Statistics Sweden and the National Board of Health and Welfare, Sweden. By using the personal identity number (PIN) that is unique to all citizens in Sweden, data will be merged together to create a research database that will be used for answering the following research questions in the study: What are the differences between the population included in the BOA Register and the general Swedish population regarding health and socioeconomic factors? What factors that predicts replacement surgery can be identified at the first registration in the BOA Register in patients with hip or knee osteoarthritis? What factors that predicts outcome after replacement surgery can be identified at the first registration in the BOA Register in patients with hip or knee osteoarthritis? Study population:The study cohort consists of all patients with a first registration (baseline) in the BOA Register between 2008 and 2016 (approximately n=75 000). These patients have sought treatment for knee and/or hip pain in primary health care in Sweden and been referred to the standardized core treatment of education and supervised exercises after confirmed clinical and/or radiographic osteoarthritis diagnose. A control cohort (approximately n=225 000) covering the general Swedish population, who never have been included in the BOA register, will be recruited from the Swedish population register at Statistics Sweden and matched (1:3) to each patient in the study cohort by the same year of birth, gender and residence (as for the study cohort at baseline). Data sources: In the study the investigators will collect the following data from the five registers: from the BOA Register: data reported by patients (e.g. most affected joint, pain, symptoms, health-related quality of life and physical activity level) and physiotherapists (e.g. earlier examinations and treatments) at baseline (the first registration before the standardized core treatment), and three and 12 months after. From the SHAR and the SKAR: patient-related and procedure-related data on all hip- and knee replacement surgeries in Sweden, including patient-reported outcomes (PROM) such as joint pain, health-related quality of life and satisfaction with treatment before surgery and one year postoperatively. From Statistics Sweden: data on socioeconomic factors and vital events such as birth, death, residence and marital status. From the National Board of Health and Welfare: data on comorbidity, health care consumption and expenditures of prescribed drugs.

Official Title
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Health and Risk Factors in Patients With Hip and Knee Osteoarthritis

Conditions
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Osteoarthritis

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: for participation in the standardized core treatment (of education and supervised exercises) and registration in the BOA Register are; pain from the knee or hip. diagnosis of osteoarthritis confirmed by a physical therapist, by medical history and a physical examination based on the clinical criteria for osteoarthritis Exclusion Criteria: for participation in the standardized core treatment and registration in the BOA Register are; confirmed or suspicion of tumor, rheumatoid arthritis, sequel hip fracture, chronic pain or fibromyalgia, total joint replacement within the past 12 months, other surgery of the knee or hip joint within the past 3 months, not able to read or understand Swedish
Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Study cohort<br>All patients with a first registration (baseline) in the BOA Register between 2008 and 2016 (approximately n=75 000). These patients have sought treatment for knee and/or hip pain in primary health care in Sweden and been referred to the standardized core treatment of education and supervised exercises after confirmed clinical and/or radiographic OA diagnose. | |
| Control cohort<br>Covering the general Swedish population, who never have been included in the BOA register, will be recruited from the Swedish population register at Statistics Sweden and matched (1:3) to each patient in the study cohort by the same year of birth, gender and residence (as for the study cohort at baseline) (approximately n=225 000). | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Replacement surgery | Information from the SHAR and the SKAR Registers on eventual replacement surgery | up to the end of 2016 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Socioeconomic factors - marital status | Data obtained from Statistics Sweden on marital status | at baseline | 
| Socioeconomic factors - education level | Data obtained from Statistics Sweden on education level | at baseline | 
| Socioeconomic factors - country of birth | Data obtained from Statistics Sweden on country of birth | at baseline | 
| Socioeconomic factors - occupation | Data obtained from Statistics Sweden on occupation | at baseline | 
| Socioeconomic factors - income | Data obtained from Statistics Sweden on income | within three years prior to baseline | 
| Socioeconomic factors - sick leave | Data obtained from Statistics Sweden on sick leave | within three years prior to baseline | 
| Consumption of drugs | Data on expenditures of prescribed drugs from the Swedish Prescribed Drug Register at the National Board of Health Care, Sweden | within three years prior to baseline | 
| Death | eventually registered as dead by Statistics Sweden | up to the end of 2016 | 
| Comorbidity | Data from the National Board of Health and Welfare on registered ICD10-codes | within three years prior to baseline | 
| Health care consumption | Data from the National Board of Health and Welfare on admission and discharge dates from health care units | within three years prior to baseline | 
| Comorbidity | Data from the National Board of Health and Welfare on registered classification of surgical interventions | within three years prior to baseline | 
| Patient-reported outcome measure on most affected joint | Data from the BOA Register on most affected joint | at baseline, and at three and 12 months | 
| Patient-reported outcome measure on fear avoidance | Data from the BOA Register on fear avoidance | at baseline, and at three and 12 months | 
| Patient-reported outcome measure on physical activity | Data from the BOA Register on physical activity level measured by questionnaire In a typical week, how much time do you spend doing physical activity | at baseline, and at three and 12 months | 
| Patient-reported outcome measure on satisfaction with treatment | Data from the BOA Register on satisfaction with treatment (the standardized core treatment) results measured by questionnaire | at baseline, and at three and 12 months | 
| Patient-reported outcome measure musculoskeletal comorbidity | Data from the BOA Register on musculoskeletal comorbidity measured in Charnley class (classifications of musculoskeletal impairment. Class A corresponds with unilateral hip or knee osteoarthritis (OA); Class B bilateral hip or knee OA; and Class C indicates multiple joint OA or some other condition that inhibits the patient's ability to walk) | at baseline, and at three and 12 months | 
| Patient-reported outcome measure on pain | Data from the BOA Register on pain in most affected joint, measured on VAS; (visual analogue scale) rating from 0-100, were 0 stands for no pain and 100 for maximum pain | at baseline, and at three and 12 months | 
| Patient-reported outcome measure on health-related quality of life | Data from the BOA Register on health-related quality of life measured by EuroQol 5-domain instrument (EQ-5D). The instrument consists of questions assessing 5 health outcome domains; mobility, self-care, usual activities, pain/discomfort and anxiety/ depression, and is summarized into a single score between 0 and 1 (full health). The instrument also includes a VAS assessing current overall health state scoring from 0 (worst imaginable health state) to 100 (best imaginable health state). | at baseline, and at three and 12 months | 
| Patient-reported outcome measure on self-efficacy | Data from the BOA Register on self-efficacy on ASES (Arthritis self-efficacy scale). ASES is a self-administered questionnaire which contains 11 items divided into 2 subgroups, self-efficacy pain and self-efficacy other symptoms. Each question is scored from 10 to 100, with moderately certain place midway between very uncertain and very certain. Each subscale is scored separately, by taking the mean of the subscale items. | at baseline, and at three and 12 months | 
| Physiotherapist-reported earlier examinations | Data from the BOA Register on earlier examinations of the affected joint prior to the standardized core treatment | at baseline and at three months | 
| Physiotherapist-reported earlier interventions | Data from the BOA Register on earlier interventions, prior to the standardized core treatment | at baseline and at three months | 
| Physiotherapist-reported compliance with intervention | Data from the BOA Register on compliance with the standardized core treatment intervention | at baseline and at three months | 
| Patient-reported outcome measures on satisfaction with treatment | Data from the SHAR and the SKAR Register on satisfaction with treatment (replacement surgery) | before replacement surgery and at follow up one year | 
| Patient-reported outcome measures - musculoskeletal comorbidity | Data from the SHAR and the SKAR Register on musculoskeletal comorbidity measured by Charnley class (Class A corresponds to unilateral hip/knee disease; Class B bilateral hip/knee disease; and Class C indicates multiple joint disease or some other condition that inhibits the patient's ability to walk). | before replacement surgery and at follow up one year | 
| Patient-reported outcome measures - pain | Data from the SHAR and the SKAR Register on pain from a VAS; visual analogue scale rating from 0-100, were 0 stands for no pain and 100 for maximum pain | before replacement surgery and at follow up one year | 
| Patient-reported outcome measures - health-related quality of life | Data from the SHAR and the SKAR Register on health-related quality of life measured by EuroQol 5-domain instrument (EQ-5D). The instrument consists of questions assessing 5 health outcome domains; mobility, self-care, usual activities, pain/discomfort and anxiety/ depression, and is summarized into a single score between 0 and 1 (full health). The instrument also includes a VAS assessing current overall health state scoring from 0 (worst imaginable health state) to 100 (best imaginable health state). | before replacement surgery and at follow up one year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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socioeconomic factors, comorbidity, replacement surgery