2 clinical trials demonstrate effective weight loss strategies for obese and overweight adults

(Press-News.org) Lifestyle interventions, including physical activity and structured weight loss programs, can result in significant weight loss for overweight, obese and severely obese adults, according to two reports that were posted online October 9 by JAMA. The studies and accompanying editorials were made available early online to coincide with the presentation of these papers at the 28th Annual Scientific Meeting of the Obesity Society. The articles appear in the October 27 print issue of JAMA.

According to background information in the papers, obesity is among the most significant public health problems of the 21st century and the prevalence of obesity has been rapidly rising for the past three decades, especially among African American women. National statistics indicate that the prevalence for overweight and obesity combined (having a body mass index of 25 or greater) is 68 percent of the population. Both papers note the increased risk of numerous other medical problems for people who are overweight or obese, including diabetes and high blood pressure. The authors also point out the lack of scientific evidence for most weight loss programs or evidence-based treatment guidelines, particularly for severe obesity.

In a one-year intensive lifestyle intervention study of diet and physical activity, Bret H. Goodpaster, Ph.D., from the University of Pittsburgh School of Medicine and colleagues, randomized a group of 130 severely obese adult individuals without diabetes in two groups to assess weight loss for a period of one year. One group was randomized to diet and physical activity for the entire 12 months, while the other group had the identical dietary intervention, but with physical activity delayed for six months. The study was conducted from February 2007 with follow-up through April 2010.

"To facilitate dietary compliance and improve weight loss, liquid and pre-packaged meal replacements were provided at no cost for all but one meal per day during months one through three and for only one meal replacement per day during months four through six of the intervention," the authors report. The physical activity component included brisk walking up to 60 minutes, five days a week. Participants were provided with a pedometer and encouraged to walk at least 10,000 steps a day. Small financial incentives for adherence to the behavioral goals of the intervention were also provided. The participants received a combination of group, individual and telephone contacts as part of the lifestyle intervention.

"Of 130 participants randomized, 101 (78 percent) completed the 12-month follow-up assessments," the authors state. The group that started with the diet and physical activity lost more weight in the first six months than the delayed-activity group (about 24 pounds as compared to 18 pounds). However, the authors report that weight loss at 12 months was about the same in the two groups (almost 27 pounds versus about 22 pounds). "Waist circumference, visceral abdominal fat, hepatic (liver) fat content, blood pressure and insulin resistance were all reduced in both groups," according to the authors.

"In conclusion, intensive lifestyle interventions using a behavior-based approach can result in clinically significant and meaningful weight loss and improvements in cardiometabolic risk factors in severely obese persons. It is also clear that physical activity should be incorporated early in any dietary restriction approach to induce weight loss and to reduce hepatic steatosis [fatty liver] and abdominal fat. Our data make a strong case that serious consideration should be given by health care systems to incorporating more intensive lifestyle interventions similar to those used in our study. Additional studies are clearly needed to determine long-term efficacy and cost-effectiveness of such approaches."

(JAMA. 2010;304[16]:1795-1802. Available at www.jama.com).

Editor's Note: This study was funded by the Commonwealth of Pennsylvania Department of Health. Co-author Jolene Brown, M.D., was supported by a National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases grant. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Please Note: For this study, there will be multimedia content available, including the JAMA Report video, embedded and downloadable video, audio files, text, documents, and related links. This content will be available at 8 a.m. CT Tuesday, October 26 at www.digitalnewsrelease.com/?q=jama_3762.

Editorial: The State of Obesity and Obesity Research

"Class II obesity (body mass index [BMI] of more than 35) and class III obesity (BMI of 40 or more) is a prevalent condition that adversely affects health," according to Donna H. Ryan, M.D. of Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, and Robert Kushner, M.D., M.S., of Northwestern University Feinberg School of Medicine, Chicago, in an accompanying editorial.

"Severe obesity is a prevalent public health problem, disproportionately affecting women and minorities. There is still much to learn about the mechanisms underlying differing risk and treatment outcomes betwpopulations. Optimal treatment approaches for class II and class III obesity are underexplored, while payment approaches for interventions known to work have yet to be adopted."

"Additional rigorous research, such as teen he clinical trial by Goodpaster et al, are needed to unravel the causes, identify prevention strategies, and develop the best treatments for obesity," they conclude.

(JAMA.2010; 304 [16]:1835-1836. Available at www.jama.com).

Editor's Note: Please see the article for additional information, author contributions and affiliations, financial disclosures, etc.

Prepared Meals and Incentivized Weight Loss Program for Obese and Overweight Women

In another article being released early online, Cheryl L. Rock, Ph.D., R.D., from Moores UCSD Cancer Center, La Jolla, Calif., and colleagues, conducted a randomized controlled trial of weight loss and weight maintenance in 442 overweight or obese women (BMI, 25 – 40), ages 18 to 69, over a two year period with follow-up between November 2007 and April 2010.

The women were randomized into three intervention groups: in-person, center-based (167 women) or telephone based (164 women) weekly one-to-one weight loss counseling, including free-of-charge prepackaged prepared foods (from Jenny Craig, Inc.) and increased physical activity for 30 minutes a day, five days a week. The participants were eventually transitioned to a meal plan that was not based mainly on the commercial program. The third group was the usual care group (111 women) who received two individualized weight loss counseling sessions with a dietetics professional and monthly contacts. All participants were provided a small monetary compensation ($25) for each completed clinic visit.

At 24 months, weight data were available for 407 of the 442 women (92.1 percent of the study sample). The average weight loss for the women participating in the center-based group was about 16 pounds or 7.9 percent of their initial weight, about 14 pounds or 6.8 percent for the telephone-based group, and about 4.5 pounds for the usual care control group. "By study end, more than half in either intervention group (62 percent of center-based [n=103] and 56 percent [n=91] of telephone-based participants) had a weight loss of at least 5 percent compared with 29 percent (n=32) of usual care participants," the authors report.

"Findings from this study suggest that this incentivized structured weight loss program with free prepared meals can effectively promote weight loss compared with usual care group," the authors comment. "Importantly, weight loss was largely maintained at two-year follow-up." They note that even small percentage weight changes can result in a reduction of risk for cardiovascular disease and diabetes.

In conclusion the authors write: "For clinical practitioners, the evidence suggests that the structured program as applied in this study provides another route for their overweight and obese patients to achieve and maintain weight loss through behavioral changes for at least a two-year period."

(JAMA. 2010;304[16]:1803-1811. Available at www.jama.com.)

Editor's Note: Dr. Rock reported serving on the advisory board for Jenny Craig from 2003 – 2004. The study was supported by Jenny Craig, Inc. (Carlsbad, Calif.), which provided program activities, materials, and prepackaged food to individuals assigned to the commercial weight loss program. Funding was provided through a clinical trial contract to the coordinating center (School of Medicine, University of California, San Diego), which subsequently disbursed funds to the collaborating clinical sites and the laboratories. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Editorial: Treatment Options for Obesity

In an accompanying editorial, Rena R. Wing, Ph.D., from the Warren Alpert Medical School, Brown University and Miriam Hospital, Providence, R.I., writes, "… the results of the trial reported by Rock et al probably represent a best-case scenario."

"The findings of this trial by Rock et al raise the possibility that if structured commercial weight loss programs could be provided free of charge to participants, both retention and average weight loss outcomes might be far better than when participants must pay for these programs."

"Currently, insurance companies will often cover the cost of bariatric surgery for obesity (estimated at $19,000 - $29,000 per patient from insurance reimbursement data) but do not cover the cost of commercial weight loss programs (such as that evaluated in this study, with estimated costs of approximately $1,600 for 12 weeks of the program and for food.) Providing commercial weight loss programs free to charge to participants might be a worthwhile health care investment."

(JAMA.2010; 304[16]:1837-1838. Available at www.jama.com).

Editor's Note: Preparation of this editorial was supported in part by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases. The sponsor had no role in the preparation, review, or approval of the manuscript.

INFORMATION: To contact Bret H. Goodpaster, Ph.D., call Amy Dugas Rose at 412-586-9776 or e-mail DugasAK@upmc.edu; to contact editorial author Donna H. Ryan, M.D., call Angela deGravelles at 225-202-5073 or e-mail prpro@eatel.net. To contact Cheryl L. Rock, Ph.D., R.D., call Kim Edwards at 619-543-2707 or cell # 619-818-6362, or email kedwards@ucsd.edu; to contact editorial author Rena R. Wing, Ph.D., e-mail Jessica Grimes at jgrimes2@lifespan.org.

For more information, contact JAMA/Archives Media Relations at 312/464-JAMA (5262) or e-mail mediarelations@jama-archives.org.