Study of Novel Approaches for Prevention (SNAP)

Wake Forest University (WFU)

Status: Completed

Conditions: Weight Gain

Treatments: Behavioral: Small Behavior Changes; Behavioral: Large Behavior Changes

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT01183689

IRB00010097

5U01HL090875 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The Study of Novel Approaches for Prevention (SNAP) is randomized trial designed to test whether behavioral interventions based on self-regulation can prevent weight gain in young adults (18-35 years; body mass index (BMI) 21-30 kg/m2). Two different self-regulation interventions for weight gain prevention will be compared in this trial; one intervention will focus on making small, consistent, changes in eating and exercise behavior to prevent weight gain or reverse weight gain if it occurs, whereas the other will emphasize larger changes in eating and exercise that occur periodically, with a goal of producing weight loss and thereby providing a buffer against anticipated weight gains. The primary aim of the trial is to test whether the magnitude of weight gain from baseline across an average three-year follow-up differs across the three groups, with the hypotheses that weight gain will be greater in the Control group than in either intervention and greater in the Small Changes than Large Changes group.

SNAP-E (Extension) will determine whether the effects of the intervention can be maintained over an additional 3 years (i.e. through a total of 6 years).

Full description

Young adults, aged 20-35 years, experience the greatest rate of weight gain, averaging 1-2 lbs/yr. Over time, this weight gain is associated with a worsening in cardiovascular disease risk factors and an increase in the prevalence of metabolic syndrome. Given the difficulties in producing sustained weight loss later in life, preventing weight gain from occurring during this critical period is key to curbing the obesity epidemic. The Study of Novel Approaches for Prevention (SNAP) is a 2-center randomized trial designed to test whether behavioral interventions based on self-regulation can prevent weight gain in young adults (18-35 years; body mass index (BMI) 21-30 kg/m2). Approximately 600 participants will be recruited over two years and randomly assigned to a control condition (N=200), self-regulation with small changes (N=200) or self-regulation with large changes (N=200). The Small Changes group will be taught to make small, consistent, changes in eating and exercise behavior to prevent weight gain or reverse weight gain if it occurs whereas the Large Changes group will emphasize periodic, larger changes in eating and exercise, with a goal of producing weight loss and thereby providing a buffer against anticipated weight gain. The primary aim of the trial is to test whether the magnitude of weight gain from baseline across an average planned follow-up of three years differs across the three groups, with a priori hypotheses that weight gain will be greater in the Control group than in either intervention and greater in the Small Changes than Large Changes group. Secondary aims are to compare the three groups on a) the proportion of participants in the three groups who gain less than 1 pound over the planned follow-up, b) the mean difference in weight gain from baseline to 24-month follow-up, c) the changes in behaviors and psychosocial measures (diet, physical activity, dietary restraint, frequency of self-weighing,depression, and occurrence of abnormal eating behaviors), and d) the changes in cardiovascular disease risk factors (blood pressure, lipids, insulin sensitivity, and waist circumference). The trial will also examine the association among changes in behaviors, weight, and cardiovascular disease risk factors and examine variables that may moderate the effects of the intervention (including gender, ethnicity, initial BMI, age) and potential mediators of the effects of the intervention (including changes in diet, activity, and self-regulatory behaviors). SNAP is member of the Early Adult Reduction in Weight Through Lifestyle Interventions (EARLY) consortium of clinical trials funded by the National Heart, Lung, and Blood Institute.

Enrollment: 599 patients

Sex: All

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. BMI of 21 - 30 kg/m2

Exclusion criteria

1. Untreated hypertension, hyperlipidemia, or type 2 diabetes, unless permission is provided by their health care provider.
2. Heart disease, heart problems or report being prescribed drugs for blood pressure or a major heart condition, unless permission is provided by their health care provider.
3. Type 1 diabetes or treatment of type 2 diabetes with insulin or oral medication that may cause hypoglycemia.
4. Health problems which may influence the ability to walk for physical activity (e.g. lower limb amputation) or other reasons why a person should not do physical activity, unless permission is provided from their health care provider.
5. Health problems that may be associated with unintentional weight change or affect the safety of a weight loss program, including report of a heart attack or stroke, chest pain during periods of activity or rest, loss of consciousness, active tuberculosis, HIV, chronic hepatitis B or C, inflammatory bowel disease requiring treatment within the past year, thyroid disease, renal disease, liver disease, hospitalization for asthma in the past year, or cancer within the past 5 years (except for non-melanoma skin cancers or early stage cervical cancer) or chronic use of steroid medication.
6. Report of a past diagnosis of or treatment for a Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition-Text Revision (DSM-IV-TR) eating disorder (anorexia nervosa or bulimia nervosa) or meet criteria for anorexia or bulimia nervosa during screening for this trial
7. Report of a past diagnosis of or current symptoms of alcohol or substance dependence.
8. Currently pregnant, pregnant within the past 6 months, or planning to become pregnant within the next 6 months.
9. History of schizophrenia, manic depression, or bipolar disorder.
10. Hospitalization for depression or other psychiatric disorder within the past 12 months.
11. Having lost and maintained a weight loss of 10 pounds or more within the past 6 months or are currently participating in a weight loss program, trying to gain weight, using steroids for muscle mass or weight gain, taking weight loss medication, or have had surgery for weight loss.
12. Participation in another weight loss or physical activity study that would interfere with this study.
13. Another member of the household (or roommate) is a participant or staff member on this trial.
14. Reason to suspect that the participant would not adhere to the study intervention or assessment schedule (i.e., can't come to group on a regular basis; will be away for more than two weeks during initial intervention phase or planning to move from the area within next year).
15. Not able to speak and understand English.
16. Residence or place of work further than 30 miles from the intervention site.
17. Perceived inability to attend the 2 year data collection visit.
18. Does not have Internet access on a regular basis.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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599 participants in 3 patient groups

Control Group

No Intervention group

Description:

"Self-Guided Behavior Changes". This group will be used to determine average rate of weight gain over 3 years with little intervention. Participants randomized to this group will receive one face-to-face session that will provide general education of self-weighing and information about both the small and large changes approach. Participants will also be provided with quarterly newsletters describing study events and very limited information on health eating.

Small behavior changes

Experimental group

Description:

Participants randomized to this group will be taught to self-weigh daily and report weights regularly. They will be reinforced for maintaining weight below randomization weight and taught that if weight exceeds randomization weight, they should reinstate small changes (e.g., modify diet by approximately 100 kcal, decrease portion sizes or change types of food, increase activity by 2000 steps/day).

Treatment:

Behavioral: Small Behavior Changes

Large behavior changes

Experimental group

Description:

Participants randomized to this group will be taught to self-weigh daily and report weights regularly. They will be reinforced for maintaining weight below randomization weight and taught that if weight exceeds randomization weight, they should reinstate large changes (e.g., modify diet to 1200-1500 or 1500-1800 kcal/day with \< 30% fat, increase exercise to 250 minutes/week of moderate intensity activity).

Treatment:

Behavioral: Large Behavior Changes