Obesity
Conditions
Keywords
obesity, weight loss, treatment
Brief summary
This study is a randomized clinical trial comparing state-of-the-art, standard behavior therapy for weight loss (SBT) with a maintenance tailored treatment (MTT) with varied behavioral prescriptions, goals, and formats over time. The overall hypothesis in the study is that the two treatment approaches will show different patterns of weight loss over time, and in particular that the MTT approach would be associated with better long-term maintenance of weight loss.
Detailed description
Recent dramatic increases in prevalence have made obesity the number one nutritional problem in the US. Of particular concern is the fact that, although available treatments are effective in producing clinically significant weight loss, their ability to sustain weight loss long term is poor. This study is based on a conceptual analysis of this problem that argues for greater attention to two issues related to the temporal dynamics of the challenge of long-term weight control. These are: 1) the environment is continually changing and is not supportive of weight control and 2) the intervention methods that are effective in inducing short-term changes in behaviors and weight often lose their potency over time because of habituation. This study is a randomized trial in which obese men and women are assigned to one of two study conditions, Standard Behavior Treatment (SBT) or Maintenance-Tailored Treatment (MTT). The MTT has adaptation to change as its central theme. A primary technique that is used to convey this theme that is different than traditional behavior treatment is that participants are asked to deliberately change weight-loss strategies systematically over time rather than to use the same approach consistently across time. Frequent change serves as a platform for teaching a larger variety of weight-control skills and thus strengthening study participants ability to adapt their weight-control strategies to changing circumstances. Changing weight-control strategies regularly also helps to reduce the extent to which habituation to strategies implemented invariantly over time diminish the salience of behavioral cues and the potency of behavioral reinforcers for sustaining weight-control efforts over time. Individuals in both treatment groups receive active intervention for a period of 18 months, followed by 12 months of no-treatment follow-up. The primary hypothesis tested is that MTT will produce larger mean weight losses at 30-month follow-up than SBT. Moreover, it is predicted that the better long-term success of the MTT group will be due primarily to better weight-loss success beyond 6 months, the point at which most people begin to regain weight with standard therapy.
Interventions
BEHAVIORALStandard Behavioral Treatment (SBT)
SBT is state-of-the-art behavioral weight loss treatment, comprised of 6 months of weekly treatment meetings followed by 6 months of biweekly meetings and 6 months of monthly meetings. Topical coverage and behavioral assignments include typical combination of energy balance information and self-control skills training. MTT has the same number of treatment contacts, but the contacts are distributed in distinct 8-week segments, each of which have a unique topic and unique behavioral assignments. Between each segment, participants are left on their own for 4 weeks with instructions to continue regular weighing but otherwise to make their own choices about what to do for weight control.
BEHAVIORALMaintenance-Tailored Treatment (MTT)
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
University of Washington
University of Minnesota
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Participants must be 18 years of age or older * Body mass index between 30.0 and 37.0
Exclusion criteria
* serious current physical disease (e.g., heart disease, cancer, and diabetes) for which physician supervision of diet and exercise would be needed. * initial fasting glucose values above 120 mg/dl * resting blood pressure at or above 90 DBP or 150 SBP will be strongly encouraged to see their primary care physician for further evaluation and will not be accepted into the study unless they do so and have physician consent for participation. * physical problems that preclude their participation in the diet and exercise components of the program * currently taking weight-loss medications * currently participating in another formal weight loss-program * currently pregnant or plan to become pregnant during the next 30 months * currently receiving treatment for a major psychological disorder or have scores on the Beck Depression Inventory above 27.0, indicative of likely clinical depression. * only one individual per household accepted into the study
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Change in Body Weight | Baseline to18 months |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change From Baseline in Energy Intake at 6 Months | Baseline and 6 months | — |
| Blood Pressure | baseline, 6, 12, 18, and 30 months | — |
| Waist-to-hip Ratio at Baseline | baseline | — |
| Blood Glucose | baseline, 6, 12, 18, and 30 months | — |
| Insulin | baseline, 6, 12, 18, and 30 months | — |
| HDL | baseline, 6, 12, 18, and 30 months | — |
| Triglycerides | baseline, 6, 12, 18, and 30 months | — |
| Physical Activity, Energy Expenditure | Baseline and 6 months | change from baseline in energy expenditure at 6 months |
| Change From Baseline in Energy Intake at 12months | 12 months | — |
| Change From Baseline in Energy Intake at 18 Months | 18 months | — |
| Waist-to-hip Ratio at 6 Months | 6 months | — |
| Waist-to-hip Ratio at 12 Months | 12 months | — |
| Waist-to-hip Ratio at 18 Months | 18 months | — |
| Waist-to-hip Ratio at 30 Months | 30 months | — |
| Mood State | baseline, 6, 12, 18, and 30 months | — |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Standard Behavioral Treatment (SBT) Standard Behavioral Treatment (SBT) for weight loss introduces a core set of instructions on diet and exercise at the beginning of the intervention and then embellishes these instructions with suggested refinements of behavioral choices over time (e.g., different menus and amounts or types of physical activity).
weight loss intervention: SBT is state-of-the-art behavioral weight loss treatment, comprised of 6 months of weekly treatment meetings followed by 6 months of biweekly meetings and 6 months of monthly meetings. Topical coverage and behavioral assignments include typical combination of energy balance information and self-control skills training. | 106 |
| Maintenance-Tailored Treatment (MTT) Maintenance-Tailored Treatment (MTT) for weight loss treats diet and exercise strategy embellishments as separate interventions with discrete and independent status. MTT differs from SBT in its emphasis on skills for long-term weight control, namely, the strategy of initiating varied weight-control strategies as a response to the demands of changing environmental challenges and to sustain effective cues and reinforcements needed to motivate weight-loss behaviors.
weight loss intervention: MTT has the same number of treatment contacts, but the contacts are distributed in distinct 8-week segments, each of which have a unique topic and unique behavioral assignments. B | 107 |
| Total | 213 |
Baseline characteristics
| Characteristic | Standard Behavioral Treatment (SBT) | Maintenance-Tailored Treatment (MTT) | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 4 Participants | 4 Participants | 8 Participants |
| Age, Categorical Between 18 and 65 years | 102 Participants | 103 Participants | 205 Participants |
| Age, Continuous | 49.1 years STANDARD_DEVIATION 10.6 | 48.5 years STANDARD_DEVIATION 10.5 | 48.8 years STANDARD_DEVIATION 10.5 |
| BMI (kg/m2) | 35.2 kg/m2 STANDARD_DEVIATION 2.8 | 34.6 kg/m2 STANDARD_DEVIATION 2.8 | 34.9 kg/m2 STANDARD_DEVIATION 2.8 |
| energy expenditure (kcal/wk) | 884.2 kcal/wk STANDARD_DEVIATION 958.7 | 954.2 kcal/wk STANDARD_DEVIATION 1267.2 | 919.2 kcal/wk STANDARD_DEVIATION 1112.95 |
| energy intake (kcal/day) | 1980.4 kcal/day STANDARD_DEVIATION 924.7 | 1976.4 kcal/day STANDARD_DEVIATION 922.7 | 1978.4 kcal/day STANDARD_DEVIATION 921.5 |
| Race (NIH/OMB) American Indian or Alaska Native | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) Asian | 2 Participants | 3 Participants | 5 Participants |
| Race (NIH/OMB) Black or African American | 21 Participants | 29 Participants | 50 Participants |
| Race (NIH/OMB) More than one race | 5 Participants | 2 Participants | 7 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 2 Participants | 4 Participants | 6 Participants |
| Race (NIH/OMB) White | 74 Participants | 69 Participants | 143 Participants |
| Region of Enrollment United States | 106 participants | 107 participants | 213 participants |
| Sex: Female, Male Female | 55 Participants | 58 Participants | 113 Participants |
| Sex: Female, Male Male | 51 Participants | 49 Participants | 100 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 29 / 106 | 26 / 107 |
| serious Total, serious adverse events | 0 / 106 | 1 / 107 |
Outcome results
Primary
Change in Body Weight
Time frame: Baseline to18 months
Population: Waist-to-hip Ratio was assessed for all Males and Females, separately, irrespective of the intervention to which participants were randomized.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Change in Body Weight | 9.3 kg | Standard Deviation 8.8 |
| Maintenance-Tailored Treatment (MTT) | Change in Body Weight | 8.3 kg | Standard Deviation 8.9 |
Secondary
Blood Glucose
Time frame: baseline, 6, 12, 18, and 30 months
Secondary
Blood Pressure
Time frame: baseline, 6, 12, 18, and 30 months
Secondary
Change From Baseline in Energy Intake at 12months
Time frame: 12 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Change From Baseline in Energy Intake at 12months | -544.1 kcal/day | Standard Error 80.7 |
| Maintenance-Tailored Treatment (MTT) | Change From Baseline in Energy Intake at 12months | -538.2 kcal/day | Standard Error 78.2 |
Secondary
Change From Baseline in Energy Intake at 18 Months
Time frame: 18 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Change From Baseline in Energy Intake at 18 Months | -326.3 kcal/day | Standard Error 128.7 |
| Maintenance-Tailored Treatment (MTT) | Change From Baseline in Energy Intake at 18 Months | -490.1 kcal/day | Standard Error 134 |
Secondary
Change From Baseline in Energy Intake at 6 Months
Time frame: Baseline and 6 months
Population: Waist-to-hip Ratio was assessed for all Males and Females, separately, irrespective of the intervention to which participants were randomized.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Change From Baseline in Energy Intake at 6 Months | -491.2 kcal/day | Standard Error 72.6 |
| Maintenance-Tailored Treatment (MTT) | Change From Baseline in Energy Intake at 6 Months | -576.4 kcal/day | Standard Error 71.1 |
Secondary
HDL
Time frame: baseline, 6, 12, 18, and 30 months
Secondary
Insulin
Time frame: baseline, 6, 12, 18, and 30 months
Secondary
Mood State
Time frame: baseline, 6, 12, 18, and 30 months
Secondary
Physical Activity, Energy Expenditure
change from baseline in energy expenditure at 6 months
Time frame: Baseline and 6 months
Population: Waist-to-hip Ratio was assessed for all Males and Females, separately, irrespective of the intervention to which participants were randomized.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Physical Activity, Energy Expenditure | 964.1 kcal/wk | Standard Error 131.8 |
| Maintenance-Tailored Treatment (MTT) | Physical Activity, Energy Expenditure | 726.4 kcal/wk | Standard Error 128.2 |
Secondary
Physical Activity, Energy Expenditure
change from baseline in energy expenditure at 12 months
Time frame: 12 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Physical Activity, Energy Expenditure | 814.8 kcal/wk | Standard Error 141 |
| Maintenance-Tailored Treatment (MTT) | Physical Activity, Energy Expenditure | 554.6 kcal/wk | Standard Error 134.9 |
Secondary
Physical Activity, Energy Expenditure
change from baseline in energy expenditure at 18 months
Time frame: 18 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Physical Activity, Energy Expenditure | 856.3 kcal/wk | Standard Error 177.6 |
| Maintenance-Tailored Treatment (MTT) | Physical Activity, Energy Expenditure | 356.0 kcal/wk | Standard Error 189.9 |
Secondary
Triglycerides
Time frame: baseline, 6, 12, 18, and 30 months
Secondary
Waist-to-hip Ratio at 12 Months
Time frame: 12 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Waist-to-hip Ratio at 12 Months | .83 ratio | Standard Error 0.01 |
| Maintenance-Tailored Treatment (MTT) | Waist-to-hip Ratio at 12 Months | .95 ratio | Standard Error 0.01 |
Secondary
Waist-to-hip Ratio at 18 Months
Time frame: 18 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Waist-to-hip Ratio at 18 Months | .83 ratio | Standard Error 0.01 |
| Maintenance-Tailored Treatment (MTT) | Waist-to-hip Ratio at 18 Months | .96 ratio | Standard Error 0.01 |
Secondary
Waist-to-hip Ratio at 30 Months
Time frame: 30 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Waist-to-hip Ratio at 30 Months | .85 ratio | Standard Error 0.01 |
| Maintenance-Tailored Treatment (MTT) | Waist-to-hip Ratio at 30 Months | .97 ratio | Standard Error 0.01 |
Secondary
Waist-to-hip Ratio at 6 Months
Time frame: 6 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Waist-to-hip Ratio at 6 Months | .84 ratio | Standard Error 0.01 |
| Maintenance-Tailored Treatment (MTT) | Waist-to-hip Ratio at 6 Months | .96 ratio | Standard Error 0.01 |
Secondary
Waist-to-hip Ratio at Baseline
Time frame: baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Behavioral Treatment (SBT) | Waist-to-hip Ratio at Baseline | .85 ratio | Standard Error 0.01 |
| Maintenance-Tailored Treatment (MTT) | Waist-to-hip Ratio at Baseline | .99 ratio | Standard Error 0.01 |