BestFIT: a Personalized Weight Loss Program

Not Applicable

Completed

Conditions: Obesity

Interventions: Behavioral: Portion-controlled meals
Behavioral: Behavioral weight loss therapy
Behavioral: Acceptance-based treatment

Registration Number: NCT02368002

Lead Sponsor: HealthPartners Institute

Brief Summary: The purpose of this study is to learn how to personalize weight loss programs. In this research we will study:

1. Whether a weight loss counselor should decide if the traditional weight loss therapy is working either after 3 or 7 weekly sessions of therapy and

2. For those who haven't lost the expected amount of weight, whether it is more effective to add packaged meals to the traditional weight loss therapy or to change to an enhanced version of behavioral weight loss therapy.

Detailed Description: The US Preventive Services Task Force recommends referral to behavioral weight loss programs to help obese adults achieve a clinically meaningful weight loss of 8-10% of starting body weight. However, approximately half of participants are unable to achieve this goal. Despite this, a"one size fits all" approach is the norm, a major drawback because those who do not respond can in fact be detected early. This gap in weight loss intervention science calls for an adaptive intervention approach that could provide the "right treatment at the right time for the right person". Adaptive interventions individualize treatment through empirically-supported decision rules advising when and how treatments should unfold over time to maximize effectiveness. Sequential Multiple Assignment Randomized Trials (SMART), developed explicitly to build the best adaptive interventions, use experimental design principles to develop these decision rules. The investigators will use a SMART to systematically evaluate therapeutic approach and timing differences for intervening with those who do not respond to a behavioral weight loss program. Self-regulation challenges have been identified as a major adherence barrier. Two attractive options to address self-regulation difficulties are: 1) supplementing behavioral treatment with Meal Replacements (MR) which decreases the need for self-regulation; and 2) switching therapeutic approaches by using an enhanced version of behavioral weight loss therapy that teaches acceptance based behavioral skills which boost capacity for self-regulation. Additionally, two time points for intervening with non-responders will be evaluated: 1) 3 weeks, based on current weight loss trial evidence; and 2) 7 weeks, based on average time used in the existing stepped care literature. Adults (n=500) will be recruited and will receive individual behavioral weight loss treatment (BWL). Participants will be randomized to either: 1) treatment response assessment at 3 weeks or 2) treatment response assessment at 7 weeks. Subjects who have lost the expected amount of weight at their assessment point, will continue with traditional behavioral weight loss therapy. For those who have not lost the expected amount of weight, we will re-randomize them to either meal replacements in addition to the traditional weight loss therapy or to the enhanced version of behavioral weight loss therapy.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 468

Inclusion Criteria

Between the ages of 21 - 70
BMI between 30 - 45 kg/m2
Able to walk 2 blocks without stopping
Able to attend measurement and intervention activities in the Twin Cities area in person for 18 months

Exclusion Criteria

Self-reported pregnancy or breastfeeding baby in last 6 months or planning a pregnancy in the next 18 months
History of bariatric surgery
Current or previous diagnosis of anorexia nervosa or bulimia nervosa
Food allergies, intolerances

Study & Design

Study Type: INTERVENTIONAL

Study Design: SEQUENTIAL

Arm && Interventions

Group	Intervention	Description
Portion-controlled meals	Portion-controlled meals	Fifty percent of participants who have not lost the expected amount of weight will be re-randomized to receive portion-controlled meals in addition to standard behavioral weight loss therapy.
Behavioral weight loss therapy	Behavioral weight loss therapy	Emphasizes 1) identifying behaviors in need of change, 2) setting goals for change, 3) monitoring progress, 4) modifying environmental cues to facilitate change, and 5) modifying consequences to motivate change.
Acceptance-based treatment	Acceptance-based treatment	Fifty percent of participants who have not lost the expected amount of weight will be re-randomized to receive an enhanced version of behavioral weight loss therapy teaching acceptance-based behavioral skills.

Primary Outcome Measures

Name	Time	Method
Weight Change	6 months and 18 months after baseline	Weight change from baseline to 6 months and to 18 months among suboptimal responders to behavioral weight loss therapy.

Secondary Outcome Measures

Name	Time	Method
Weight Change	6 and 18 months after baseline	Mixed model-estimated weight change from baseline to 6 and 18 months (pooled) among all randomized participants.