HealthyTogether: RCT of a Dyadic Weight Management Intervention

Harnessing the Power of Social Support for Weight Management: a Randomized Controlled Trial of HealthyTogether

Four in five Veterans have overweight or obesity. However, few eligible Veterans achieve meaningful weight loss in VA's national MOVE! Weight Management Program. Family and friends strongly influence a person's health behaviors and weight. Including a close family member or friend in weight management may improve weight management outcomes. This study will test whether an 14-week, 8-session virtual weight management program that includes Veterans and a support person (e.g., family member or friend) leads to weight loss. The investigators will also test whether the program leads to improvements in weight-related health behaviors, including physical activity and diet, and relationship quality.

The prevalence of overweight and obesity is more than 80% among VA users, increasing risk of morbidity and mortality. In 2006, VA nationally implemented the MOVE! Weight Management Program, an evidence-based behavioral weight management program. Effectiveness of MOVE! is suboptimal: <20% of all participants and only 30% of those with intense and sustained participation achieve clinically meaningful weight loss. Furthermore, only 8-9% of eligible Veterans attend any MOVE! sessions and, among those who do, half attend only a single session. Taken together, <2% of the 3.2 million eligible Veterans lose clinically meaningful weight in MOVE!. Therefore, additional weight management approaches are needed to address obesity at the VA population-level.

One strategy to improve behavioral weight management effectiveness is by leveraging social relationships. Social support improves weight management program initiation, retention, and short and long-term weight loss and is also a major driver of weight-related behaviors, such as physical activity and diet quality. However, social relationships can also impede weight management, for example, when close others (e.g., family and friends) undermine or do not support behavior change. The key to addressing this double-edged sword of social relationships may be through dyadic approaches that include close others in behavioral weight management with a focus on improving communication and relationship quality.

HealthyTogether is a brief, virtual weight management program for Veterans and a close other ("partner"). Over 14 weeks, individual dyads receive 8 hour-long video sessions with a clinician. Session content includes physical activity, diet, and weight management medication education; goal setting; and relationship and communication skills training and practice, informed by evidence-based dyadic treatments. This study is a two-site hybrid type I effectiveness-implementation randomized controlled trial with a primary focus on evaluating effectiveness of HealthyTogether and a secondary focus on understanding determinants of implementation. The aims of the trial are:

1. Test whether HealthyTogether results in greater weight loss than usual care at 6 months among Veterans (primary).
2. Examine differences between HealthyTogether and usual care groups in secondary Veteran and partner outcomes, including health behaviors (i.e., diet, physical activity) and relationship quality.
3. Examine Veteran and partner contributions to changes in their own and each other's outcomes using dyadic analyses, informing potential future intervention targets.
4. Assess determinants of implementation, including cost, feasibility, acceptability, and appropriateness, guided by the Consolidated Framework for Implementation Research, to inform future implementation.

Considering the burden of overweight and obesity in VA and the limited reach and effectiveness of MOVE!, HealthyTogether has the potential to address multiple VA priorities: mitigate obesity-related chronic disease and involve family in Veterans' care. Study findings will inform VA National Center Health for Health Promotion and Disease Prevention efforts to expand effective, evidence-based weight management services for Veterans.

Inclusion Criteria:

Veteran participants:

• Assigned to a VA primary care provider
• Have a weight measurement (BMI>=30) recorded in the VA medical record within 16 weeks prior to enrollment
• Have a second, valid weight measurement recorded in the VA medical record within the prior year
• Have a BMI>=30 at enrollment
• Able to participate in virtual intervention sessions during regular business hours

Partner participants:

• Able to participate in virtual intervention sessions during regular business hours
• Speak with Veteran at last weekly
• Live in the same state where Veteran receives VA care

Exclusion Criteria:

Veterans are excluded if:

• not fluent in English
• have severe hearing loss prohibiting participation
• have a dementia diagnosis
• have recently (within the past 3 months) participated in a clinical or research behavioral weight management program
• have a history of (within past 2 years) or plans to (within next 6 months) have bariatric surgery
• are pregnant, postpartum, nursing, or planning to become pregnant within 6 months
• are receiving cancer (non-skin) treatment
• have drug or alcohol dependence not in remission, a recent suicide attempt, active psychosis, or an active behavior flag in the medical record
• report high-levels of alcohol use (AUDIT-C score >=8)
• are receiving hospice or palliative care
• are living in a nursing home or assisted living facility
• are enrolled in VA home-based primary care
• have end stage renal disease
• have a current or past diagnosis of anorexia or bulimia
• have had an inpatient hospitalization in the past 3 months
• weigh more than 440 pounds (this is the upper limit of the study's scales)

Partners are excluded if:

• not fluent in English
• have severe hearing loss prohibiting participation
• endorse having a health condition that may limit their ability to participate in the intervention
• report high-levels of current alcohol use (AUDIT-C score >=8)
• are receiving hospice or palliative care
• are living in a nursing home or assisted living facility