Obesity
Conditions
Keywords
weight loss, weight maintenance, weight control, peer support, patient-provided care
Brief summary
The primary aim of this study is to test the efficacy of patient-provided treatment for weight-loss maintenance.
Interventions
BEHAVIORALPeer-delivered Weight Maintenance
Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive an 18-month patient-delivered behavioral weight maintenance intervention. Specifically, group sessions will be delivered by a mentor (i.e., successful weight loser) and weekly coaching will be delivered by a peer (other member of their weight maintenance group).
BEHAVIORALProfessionally-Delivered Weight Maintenance
Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive an 18-month reduced intensity behavioral weight maintenance intervention, delivered by a professional. The intervention will consist of 24 group sessions.
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Stanford University
The Miriam Hospital
University of Connecticut
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
* Age between 18-75 * Body Mass Index between 25-50 * English Speaking
Exclusion criteria
* Report being unable to walk 2 blocks without stopping * Are currently participating in weight loss treatment, have a history of bariatric surgery, or lost ≥5% in the past 6-months * Are pregnant or plan to become pregnant within 1 year * Report a heart condition, chest pain during periods of rest or activity, or loss of consciousness on the Physical Activity Readiness Questionnaire * Report a medical condition that could jeopardize their safety in a weight control program with diet and exercise guidelines * Report conditions that, in the judgment of the PI, would render them unlikely to follow the protocol (e.g., relocation, dementia, unable to read and write in English) * Have no Internet access.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Weight Change (kg) | Baseline to 18-months | Weight change (measured on a digital scale to the nearest 0.1-kilogram) from Phase II Baseline (post-Phase I) to the end of the Phase II maintenance program (18 months). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Blood Pressure (mmHg) | Baseline to 18-months | Blood pressure (mmHg) from Phase II Baseline (post-Phase I) to the end of the Phase II maintenance program (18 months). |
Countries
United States
Participant flow
Pre-assignment details
Following enrollment, participants began Phase I, a 16-week weight loss program aiming to induce clinically significant weight loss (5% of starting body weight). After Phase I, eligibility to continue to Phase II (weight maintenance) was evaluated. Those who lost at least 5% of their body weight remained eligible. Given that Phase II was the primary focus of the study, primary outcome data were analyzed only from randomized, Phase II participants (eligible subset of Phase I participants).
Participants by arm
| Arm | Count |
|---|---|
| Phase I: Weight Loss Phase and Phase II (RCT): Peer-Delivered Weight Maintenance Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive an 18-month patient-delivered behavioral weight maintenance intervention. Specifically, group sessions will be delivered by a mentor (i.e., successful weight loser) and weekly coaching will be delivered by a peer (other member of their weight maintenance group).
Peer-delivered Weight Maintenance: Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive an 18-month patient-delivered behavioral weight maintenance intervention. Specifically, group sessions will be delivered by a mentor (i.e., successful weight loser) and weekly coaching will be delivered by a peer (other member of their weight maintenance group). | 153 |
| Phase I: Weight Loss Phase and Phase II (RCT): Professionally-Delivered Weight Maintenance Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive an 18-month reduced intensity behavioral weight maintenance intervention, delivered by a professional. The intervention will consist of 24 group sessions.
Professionally-Delivered Weight Maintenance: Contingent upon participants losing 5% of body weight or more in Phase I (weight loss) of this trial, participants will receive an 18-month reduced intensity behavioral weight maintenance intervention, delivered by a professional. The intervention will consist of 24 group sessions. | 134 |
| Phase I Only (Weight Loss Phase): 16 Weeks This group consists of the participants who enrolled in Phase I (Weight Loss Phase) but were not randomized to Phase I because they dropped out or were not eligible for Phase II (Weight Maintenance Phase). | 562 |
| Total | 849 |
Baseline characteristics
| Characteristic | Phase I: Weight Loss Phase and Phase II (RCT): Professionally-Delivered Weight Maintenance | Phase I: Weight Loss Phase and Phase II (RCT): Peer-Delivered Weight Maintenance | Total | Phase I Only (Weight Loss Phase): 16 Weeks |
|---|---|---|---|---|
| Age, Continuous | 54.8 Years STANDARD_DEVIATION 11.7 | 52.6 Years STANDARD_DEVIATION 11.7 | 50.5 Years STANDARD_DEVIATION 12.3 | 48.9 Years STANDARD_DEVIATION 12.2 |
| Blood pressure (mmHg) Diastolic Blood Pressure | 76.8 mm Hg STANDARD_DEVIATION 9.3 | 76.4 mm Hg STANDARD_DEVIATION 8.3 | 76.6 mm Hg STANDARD_DEVIATION 8.7 | — |
| Blood pressure (mmHg) Systolic Blood Pressure | 118.4 mm Hg STANDARD_DEVIATION 13.2 | 118.6 mm Hg STANDARD_DEVIATION 15.6 | 118.5 mm Hg STANDARD_DEVIATION 14.5 | — |
| Ethnicity (NIH/OMB) Hispanic or Latino | 18 Participants | 13 Participants | 125 Participants | 94 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 116 Participants | 140 Participants | 690 Participants | 434 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 34 Participants | 34 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 1 Participants | 0 Participants | 3 Participants | 2 Participants |
| Race (NIH/OMB) Asian | 5 Participants | 6 Participants | 26 Participants | 15 Participants |
| Race (NIH/OMB) Black or African American | 19 Participants | 15 Participants | 121 Participants | 87 Participants |
| Race (NIH/OMB) More than one race | 5 Participants | 7 Participants | 28 Participants | 16 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 1 Participants | 0 Participants | 1 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 2 Participants | 0 Participants | 49 Participants | 47 Participants |
| Race (NIH/OMB) White | 101 Participants | 125 Participants | 621 Participants | 395 Participants |
| Region of Enrollment United States | 134 participants | 153 participants | 849 participants | 562 participants |
| Sex: Female, Male Female | 111 Participants | 129 Participants | 704 Participants | 464 Participants |
| Sex: Female, Male Male | 23 Participants | 24 Participants | 145 Participants | 98 Participants |
| Weight (kg) | 85.4 kilograms STANDARD_DEVIATION 17.4 | 82.9 kilograms STANDARD_DEVIATION 15.3 | 84.0 kilograms STANDARD_DEVIATION 16.3 | — |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 153 | 0 / 134 | 0 / 562 |
| other Total, other adverse events | 103 / 153 | 89 / 134 | 18 / 562 |
| serious Total, serious adverse events | 36 / 153 | 22 / 134 | 0 / 562 |
Outcome results
Primary
Weight Change (kg)
Weight change (measured on a digital scale to the nearest 0.1-kilogram) from Phase II Baseline (post-Phase I) to the end of the Phase II maintenance program (18 months).
Time frame: Baseline to 18-months
Population: The number of participants analyzed in this outcome measure reflects the number that completed this measure at the 18 month assessment (primary outcome assessment). All missing participant data indicates that the participant did not complete this assessment procedure.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Peer-Delivered Weight Maintenance | Weight Change (kg) | 1.2 kilograms | Standard Deviation 7 |
| Professionally-Delivered Weight Maintenance | Weight Change (kg) | 2.5 kilograms | Standard Deviation 6 |
Secondary
Blood Pressure (mmHg)
Blood pressure (mmHg) from Phase II Baseline (post-Phase I) to the end of the Phase II maintenance program (18 months).
Time frame: Baseline to 18-months
Population: The number of participants analyzed in this outcome measure reflects the number that completed this measure at the 18 month assessment (primary outcome assessment). All missing participant data indicates that the participant did not complete this assessment procedure.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Peer-Delivered Weight Maintenance | Blood Pressure (mmHg) | Diastolic Blood Pressure | 3.3 mmHg | Standard Deviation 8.2 |
| Peer-Delivered Weight Maintenance | Blood Pressure (mmHg) | Systolic Blood Pressure | 2.5 mmHg | Standard Deviation 13.4 |
| Professionally-Delivered Weight Maintenance | Blood Pressure (mmHg) | Systolic Blood Pressure | 4.0 mmHg | Standard Deviation 14.2 |
| Professionally-Delivered Weight Maintenance | Blood Pressure (mmHg) | Diastolic Blood Pressure | 4.6 mmHg | Standard Deviation 9.4 |