Independent Weight Loss Maintenance for Communities With Arthritis in North Carolina: the I-CAN Clinical Trial

Study Overview
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Brief Summary
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The study team is currently conducting a pragmatic, community-based assessor-blinded randomized controlled trial (RCT) in overweight and obese adults > 50 years with knee OA in both urban and rural counties in North Carolina. As the participants randomized to the 18 month diet and exercise group in the WE-CAN study successfully complete the intervention (≥ 5% weight loss), the study team has the unique opportunity to evaluate the effectiveness of a theoretically-based tapered weight maintenance intervention. Eligible participants will be randomized to either the weight-loss maintenance or health education attention control groups.

Detailed Description
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Results from the Intensive Diet and Exercise for Arthritis (IDEA) trial showed that 10% diet-induced weight loss combined with exercise (D+E) was twice as effective at relieving knee pain and improving function and mobility as previous long-term weight loss and exercise programs in similar cohorts. The treatment effects of D+E on these clinical outcomes were mediated by changes in self-efficacy over the course of the trial. However, most people tend to regain most or all of the lost weight in three to five years. The challenge is maintaining the weight loss and sustaining the efficacy of the intervention. Our current trial (WE-CAN) is designed to adapt the successful IDEA intervention to real-world clinical and community settings. As WE-CAN participants in the D+E group complete their intervention, the investigators will leverage our organizational infrastructure to maintain weight-loss without supervised intervention by increasing participant confidence to establish and adhere to a routine of good exercise and diet behaviors independently. Participants will include 212 older adults aged ≥ 51 yrs. with knee osteoarthritis (OA) who achieved a weight loss ≥ 5% in the D+E intervention arm of the WE-CAN trial. All WE-CAN participants meet the ACR clinical criteria for knee OA, which includes knee pain on most days of the week plus at least three of the following six: age ≥ 50 years, stiffness < 30 min/day, crepitus, bony tenderness, bony enlargement, and/or no palpable warmth. Eligible WE-CAN D+E participants will be randomized to either 6-month facilitated weight-loss maintenance or health education control interventions. The primary aim is to compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on maintaining weight loss subsequent to a 12-month unsupervised follow-up period. Secondary aims will compare the two interventions on WOMAC knee pain and function, health-related quality of life (SF-36), 6-minute walk distance, and weight-loss maintenance self-efficacy following the 12-month unsupervised period. The study team will also establish the cost-effectiveness of a 6-month facilitated weight-loss maintenance intervention for older adults with knee OA by conducting cost-effectiveness and budgetary impact analyses using data from the current trial in a validated computer-simulated model of knee OA. There have been numerous attempts to prevent weight regain in adults. This study is significant in that it is designed to encourage older adults with knee OA that have experienced significant weight loss to develop strategies that will build self-efficacy for maintaining weight loss on their own long after the active intervention ends.

Official Title
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Independent Weight Loss Maintenance for Communities With Arthritis in North Carolina: the I-CAN Clinical Trial

Conditions
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Osteo Arthritis Knee

Intervention / Treatment
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* Behavioral: Weight-Loss Maintenance
* Behavioral: Health Education (Attention Control)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age ≥ 51 achieved a weight loss ≥ 5% in the D+E intervention arm of the WE-CAN trial Exclusion Criteria: Weight loss < 5% of baseline body weight Significant co-morbid disease that would threaten safety or impair ability to participate in interventions or testing (Blindness; Type 1 diabetes; Severe coronary artery disease) Inability to finish 18-month study or unlikely to be compliant (Planning to leave area > 2 month during the next 18 months)

Ages Eligible for Study
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Minimum Age: 51 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants will include 212 older adults aged ≥ 51 yrs. with knee OA who achieved a weight loss ≥ 5% in the D+E intervention arm of the WE-CAN trial. Eligible WE-CAN D+E participants will be randomized to either the weight-loss maintenance or health education attention control groups.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Weight-Loss Maintenance<br>Weight Loss Maintenance Intervention | Behavioral: Weight-Loss Maintenance<br>* Over the course of the first 6-months, participants will build their self-efficacy to maintain weight loss on their own, empowered to do what is needed to achieve personal goals and long-term behavior change (months 7-18). The first 6 months of I-CAN will prepare participants for successful independent weight-loss maintenance in months 7-18. During the 12-month independent weight-loss maintenance phase participants exercise on their own and maintain their weight loss (or increase weight loss if they choose) with the only contact from interventionists being two newsletters at months 9 and 15.<br>|
| Active Comparator: Health Education (Attention Control)<br>Health Education Intervention | Behavioral: Health Education (Attention Control)<br>* Participants in the control group will attend an individual session during month 1, and a monthly face-to-face group meeting during months 2-6. The sessions will provide attention, social interaction, and physician-based health education. Participants will receive a newsletter during months 9 and 15.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight-Loss Maintenance | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on maintaining weight loss subsequent to a 12-month unsupervised follow-up period. | 18 Months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Knee Pain measured by the WOMAC Index | The investigators will measure self-reported pain using the WOMAC (scores will be pulled from the KOOS Questionnaire in which the WOMAC is embedded). The pain index assesses participants' pain on a scale, ranging from 0 (none) to 4 (extreme). The pain subscale consists of 5 items and total scores can range from 0-20, with larger scores indicating greater dysfunction. | 18 Months | 
| Function measured by the WOMAC Index | The investigators will measure self-reported physical function using the WOMAC (scores will be pulled from the KOOS Questionnaire in which the WOMAC is embedded). The LK version asks participants to indicate on a scale from 0 (none) to 4 (extreme) the degree of difficulty experienced in the last week due to knee OA. Individual scores for the 17 items are totaled to generate a summary score that could range from 0-68, with higher scores indicating poorer function. | 18 Months | 
| Health Related Quality of Life: SF-36 | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on health-related quality of life (SF-36) subsequent to a 12-month unsupervised follow-up period. Two summary scores are acquired: physical health and mental health. Range=0-100. Higher scores indicate better health. | 18 Months | 
| Mobility- 6 minute walk test | The primary mobility measure will be 6-minute walk distance. Participants are told to walk as far as possible in 6 minutes on an established course. | 18 Months | 
| Self-Efficacy - Perceived Stress: questionnaire | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The perceived stress questionnaire will measure the degree to which people perceive their lives as stressful. Range = 0-40. Higher numbers indicate higher stress. | 18 Months | 
| Self-Efficacy - Walking Efficacy for Duration: walking efficacy for duration scale | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The walking efficacy for duration scale measures one's ability to walk/jog at a moderately fast pace for various durations. Range 0-100. A higher score indicates a higher self-efficacy. | 18 Months | 
| Self-Efficacy - PANAS | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The Positive and Negative Affect (PANAS) measures both positive and negative affect, leading to more insightful outlooks regarding participants' feeling states. This scale consists of 20 items that reflect the intensity of how the participant feels right now. Range=10-50 for each subscale. A higher score for positive affect indicates a higher level of positive affect. A higher score for negative affect indicates a higher level of negative affect. | 18 Months | 
| Self-Efficacy - Gait Efficacy - gait efficacy/environmental efficacy scale | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The gait efficacy/environmental efficacy scale will ask the participants' confidence in performing certain activities. Confidence in performing activities. Participants will be asked to indicate their level of confidence being able to complete different tasks. Range=0-100. A higher score indicates higher self-efficacy. | 18 Months | 
| Self-Efficacy - Satisfaction with Life: Satisfaction with life scale | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The Satisfaction with life scale is focused to assess global life satisfaction. Range=5 to 35. A higher scale indicates a higher level of life satisfaction. | 18 Months | 
| Self-Efficacy - Weight Efficacy Scale | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The Weight Efficacy Lifestyle Questionnaire (WEL) is a 20-item measure employed to assess self-efficacy for weight management. Range=0 to 180. Higher numbers indicate better confidence. | 18 Months | 
| Self-Efficacy - Adherence Self Efficacy Scale | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The adherence questionnaire is designed to assess beliefs in one's ability (confidence) to continue exercising at various intensities and frequencies. Range=0-100. A higher score indicates higher self-efficacy. | 18 Months | 
| Self-Efficacy - Barriers Self-Efficacy to Exercise | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The Barriers Self-Efficacy to Exercise measures confidence in dealing with barriers to exercise. Range=0-100. Higher numbers indicate higher confidence. | 18 Months | 
| Self-Efficacy - Multidimensional Outcome Expectations for Exercise Scale (MOEES): questionnaire | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The MOEES questionnaire consists of three subscales: physical outcome expectations (score range 6-30), social outcome expectations (score range 4-20), and self-evaluative outcome expectations (score range 5-25). Each subscale is scored by summing the numerical ratings for each response. Higher scores are indicative of higher levels of outcome expectations for exercise. | 18 Months | 
| Self-Efficacy - Perceived Barriers: questionnaire | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy. The perceived barriers questionnaire measures a person's perceptions to barriers to performing exercise. The questionnaire is scored by finding the mean for each response (range = 1-5). Higher scores indicate higher perception of barriers. | 18 Months | 
| Self-Efficacy - Weight Loss Maintenance: questionnaire | Compare the effects of a 6-month weight-loss maintenance intervention grounded in social cognitive theory to a health education intervention on self-efficacy for maintaining weight loss. Range=0-100. Higher scores indicate more confidence in maintaining weight loss. | 18 Months | 
| Cost-Effectiveness | Resource utilization will be collected by questionnaire. MD and non-MD office visits will be collected via self-report with domains including visits to clinicians (physicians, nurses, physical therapists, others), tests, medications, injections, surgery, alternative therapies. The number of visits associated with utilization of each of 4 domains, MD visits, non-MD visits, ED visits, and inpatient stays, will be examined. | 18 Months | 
| Cost-Effectiveness- WPAI | The Work Productivity and Activity Impairment index (WPAI) will be used to assess absenteeism and reduced productivity while at work (presenteeism). Outcome (OC) scores can be derived from the WPAI: OC1, percent work time missed due to health, (percentage of absenteeism); percent impairment while working due to health, (percentage of presenteeism); percent overall work impairment due to health, percent activity impairment due to health. For all 4 outcomes, greater scores (range 0-100%) indicate greater impact of health. | 18 Months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Arthritis, Knee, weight loss