March 17, 2008 — In overweight and obese patients at risk for cardiovascular disease (CVD), a behavioral weight loss intervention was successful and allowed patients to maintain the weight loss, according to the results of a randomized controlled trial reported in the March 12 issue of the Journal of the American Medical Association.
"Behavioral weight loss interventions achieve short-term success, but regain is common," write Laura P. Svetkey, MD, from the Duke University Medical Center in Durham, North Carolina, and colleagues from the Weight Loss Maintenance Collaborative Research Group. "Together overweight and obesity are the second leading cause of preventable death, primarily through effects on cardiovascular disease (CVD) risk factors (hypertension, dyslipidemia, and type 2 diabetes)."
The goal of this 2-phase trial was to compare 2 weight loss maintenance interventions with a self-directed control group; 1032 overweight or obese adults with hypertension, dyslipidemia, or both who had lost at least 4 kg during a 6-month weight loss program (phase 1) were randomized to a weight-loss maintenance intervention (phase 2). Participants were enrolled at 4 academic centers from August 2003 through July 2004 and were randomized from February to December of 2004, with data collection completed in June 2007.
After phase 1, participants were randomized to 1 of the following weight-loss maintenance interventions for 30 months: monthly personal contact, unlimited access to an interactive technology–based intervention, or self-directed control. The primary endpoint was changes in weight from randomization.
The study sample was 38% African American and 63% women; mean entry weight was 96.7 kg. During phase 1, mean weight loss was 8.5 kg, and there was some weight regain after randomization, but overall, 71% of study participants remained below entry weight.
In the personal-contact group, participants regained less weight (4.0 kg) vs those in the self-directed group (5.5 kg; mean difference at 30 months, −1.5 kg; 95% confidence interval [CI], −2.4 to −0.6 kg; P = .001). Weight regain at 30 months was statistically similar in the interactive technology−based group (5.2 kg) and self-directed group (5.5 kg; mean difference, −0.3 kg; 95% CI, −1.2 to 0.6 kg; P = .51). However, weight regain was lower at 18 months in the interactive technology–based vs the self-directed group (mean difference, −1.1 kg; 95% CI, −1.9 to −0.4 kg; P = .003) as well as at 24 months (mean difference, −0.9 kg; 95% CI, −1.7 to −0.02 kg; P = .04). The difference between the personal-contact and interactive technology–based groups at 30 months was −1.2 kg (95% CI, −2.1 to −0.3; P = .008). The findings were not significantly different in subgroups based on sex, race, age, and body mass index (BMI).
"The majority of individuals who successfully completed an initial behavioral weight loss program maintained a weight below their initial level," the study authors write. "Monthly brief personal contact provided modest benefit in sustaining weight loss, whereas an interactive technology–based intervention provided early but transient benefit."
Limitations of the study are that only individuals who had successfully lost weight in phase 1 were randomized into phase 2; there were very few Hispanic participants; dietary and physical activity measures may not accurately reflect energy intake and expenditure; the duration of intervention was only 3 years; and the outcome was weight loss maintenance, not cardiovascular (CV) events.
"Future research should focus on longer intervention and follow-up, understanding predictors of successful maintenance and further refinement of both personal contact and interactive technology–based interventions," the study authors conclude.
The National Heart, Lung, and Blood Institute supported this study. Some of the study authors have obtained funding. The other study authors have disclosed no relevant financial relationships.
JAMA. 2008;299:1139-1148.
Clinical Context
Nearly two thirds of Americans are overweight or obese. Weight loss reduces CV risk factors associated with obesity, but weight regain is an intractable problem, and practical scalable interventions to maintain weight loss are needed. Observational studies suggest that personal contacts, self-monitoring of weight and activity, and accountability contribute to maintenance of weight loss, but clinical trials are needed to verify their efficacy.
This is a comparison of 3 strategies to maintain weight loss during a 30-month period after an initial weight loss of at least 4 kg in patients with overweight and obesity, conducted as phase 2 of the Weight Loss Maintenance trial in a large, diverse adult population at high risk for CVD.
Study Highlights
- Included were adults with a BMI between 25 and 45 kg/m2 with CV risk factors such as hypertension, taking CV medications for dyslipidemia but with no active disease such as angina, and those who had a telephone and access to the Internet.
- Excluded were those with medication-treated diabetes, recent CV event or psychiatric disorder, weight loss of more than 9 kg within 3 months, or previous weight loss surgery.
- The first phase of the trial consisted of a 6-month behavioral weight loss program with 20 weekly sessions, and only those with weight loss of at least 4 kg were recruited into the second phase.
- Randomization was stratified by clinic, race, and amount of weight lost.
- Data collection occurred at baseline and every 6 months for 30 months.
- Dietary intake and physical activity were measured at entry, randomization, and at 12 and 30 months of follow-up, and diet was assessed by the Block food frequency questionnaire.
- Physical activity was measured by accelerometry.
- Both the personal-contact and Web-based interactions used motivation, support, relapse prevention, and problem solving as principles, whereas the control self-directed group received minimal intervention.
- The interactive Web-based program allowed participants to set personal goals and included email reminders to log in regularly with telephone call reminders if participants failed to log in after 2 emails.
- Personal-contact intervention consisted of monthly person-to-person telephone calls of 5 to 15 minutes and a face-to-face meeting of 45 to 60 minutes every fourth month, without any Internet contact.
- Primary outcome was change in weight from randomization to 30 months.
- Secondary outcomes were maintenance of at least a 4-kg weight loss, at least 5% weight loss from time of first entry to the first weight loss program, and no more than a 3% weight gain from randomization.
- Of 1685 participants in the first 6-month weight loss program, 1032 qualified for the maintenance program.
- 63% were women and 38% were African American, mean age was 55 .6 years, and mean initial weight loss was 8.5 kg.
- Follow-up rates were 93% to 96% at each visit.
- Those in the interactive program logged in an average of once weekly and had contact 77% of the time for 30 months.
- Those in the personal-contact group completed an average of 91% of monthly contacts.
- All 3 groups regained weight with a mean of 5.5 kg for the self-directed, 5.2 kg for the Web-based, and 4.0 kg for the personal-contact groups.
- Mean weight at 30 months remained lower vs the time of entry into the first 6 months.
- 41.8% maintained at least a 4-kg weight loss, and 70.9% remained at or below their entry weight with more patients in the personal-contact group maintaining this goal vs the self-directed group (P = .003).
- 37.1% overall remained 5% or more below the program entry weight.
- At 30 months, those in the personal-contact group regained 1.5 kg less weight than those in the self-directed group (P = .001).
- Those in the Web-based group regained 0.3 kg less than those in the self-directed group (P = .51).
- Those in the personal-contact group regained 1.2 kg less than those in the Web-based group (P = .008).
- The results were similar when outcomes were expressed as weight change and independent of race, sex, and baseline BMI.
- At 24 months after randomization, those in the Web-based group showed less weight regain than those in the self-directed group.
- The authors concluded that the personal-contact intervention was more effective at preventing or reducing weight regain but that the interactive Web-based intervention was effective before 30 months.
Pearls for Practice
- Monthly personal contact, an interactive Web-based intervention, and self-directed weight maintenance are associated with maintenance of weight loss at 30 months after a weight loss program.
- Personal contact is more effective than a Web-based intervention or self-directed care for weight maintenance for 30 months after weight loss.
Dr. José Manuel Ferrer Guerra
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