Comparison of 2 Weight Loss Strategies

Overweight or obese patients, who are at high risk for chronic disease, can benefit from interventions aimed at weight loss as first-line treatment for obesity-related conditions. Some patients are able to achieve 8% to 10% weight loss with 6 months of lifestyle interventions, however, not all obese adults are able to achieve or maintain that much weight loss.

The majority of interventions aimed at weight loss begin with a high level of intensity, but become less intensive over time. In addition, the schedule for contact with participants remains fixed regardless of the success or failure of the treatment. Because intensive weight loss programs are expensive and require substantial time commitments, they are often impractical for many patients.

A stepped-care approach to weight loss may be an alternative. Stepped care involves an initially low-intensity intervention that is increased if weight loss milestones are not reached at prespecified time points. Researchers recently conducted a study to test the hypothesis that a stepped-care weight loss intervention (STEP) would result in greater weight loss compared with a standard behavioral weight loss intervention (SBWI). They reported the study results in the Journal of the American Medical Association [2012;307(24):2617-2626].

The randomized clinical trial included 363 adults classified as overweight or obese (body mass index, 25 to <40). Participants were 18 to 55 years of age, 33% were nonwhite, and 83% were female. They were randomized to SBWI (n=165) or STEP (n=198). The trial was conducted at 2 universities affiliated with US academic medical centers. Enrollment was conducted between May 2008, and February 2010; data collection was completed in September 2011.

The main outcome measure was mean change in weight over 18 months; secondary outcome measures were resting heart rate and blood pressure, waist circumference, body composition, fitness, physical activity, dietary intake, and cost of the program.

The interventions for both groups included a low-calorie diet, prescribed increases in physical activity, and group counseling sessions (weekly or monthly) during an 18-month period. Participants in the SBWI group were assigned to a fixed program. For those in the STEP group, the frequency of counseling, type, and weight loss strategies could be modified every 3 months in response to weight loss as related to weight loss goals.

There was a significant group ´ time interaction (P=.03) for weight loss, indicating that the pattern of weight loss over the 18-month study period was different between the 2 groups. Overall weight loss favored the SBWI group.

At 6 months, the weight loss -9.6 kg (P<.001) in the SBWI group compared with -7.6 kg in the STEP group (P<.001). The percentage change in weight from baseline was -10.4% (P<.001) in the SBWI group compared with -8.2% (P<.001) in the STEP group.

At 18 months, weight loss in the SBWI group was -7.6 kg (P<.001) compared with -6.2 kg in the STEP group (P<.001); percentage change in weight from baseline was -8.1% (P<.001) in the SBWI group compared with -6.9% in the STEP group (P<.001).

There was a difference in cost between the 2 groups: cost per participant in the SBWI group was $1357 (P<.001) compared with $785 for the STEP group (P<.001). Both groups had significant improvements in resting heart rate, blood pressure, and fitness.

In summary, the researchers stated, “Among overweight and obese adults, the use of SBWI resulted in a greater mean weight loss than STEP over 18 months. Compared with SBWI, STEP resulted in clinically meaningful weight loss that cost less to implement."