Do Do-It-Yourself Interventions For Obesity Work?
Given that most people do not look at obesity as a chronic disease that requires professional management, the most common approach to losing weight is still for people to try to lose weight on their own. But just how effective are these do-it-yourself approaches to weight management? This is the topic of a systematic review and meta-analysis by Jamie Hartmann-Boyce and colleagues from Oxford University, published in the American Journal of Public Health. Self-help programs were defined as self-directed interventions that do not require professional input to deliver (“self-help”) across a variety of formats, including but not limited to print, Internet, and mobile phone-delivered programs. As such programs come in all shapes and sizes, the researchers also distinguished between “tailored” interventions as those in which participant characteristics were used to provide individualized content (e.g., tailored based on information provided by participants at baseline), and “interactive” interventions as those programs in which participants could actively engage with intervention content (e.g., through online quizzes or entering their own content). For each intervention, the authors also coded the specific type of self-managment strategies ranging from goal setting to buddy systems. The researchers found 23 randomized controlled trials comparing self-help interventions with each other or with minimal controls in overweight and obese adults, with 6 months or longer follow-up. Together these studies included almost 10,000 participants in 39 intervention arms. Although the researchers noted considerable heterogeneity among studies, the average difference in weight loss at 6 months between the self-management and control groups was about 2 Kg, an effect that was no longer significant at 12 months. Overall the type of program (tailored vs. non-tailored, interactive vs. non-interactive, etc.) did not make any notable difference to the success of participants. The authors also noted that the only trial that examined a potential interaction with socioeconomic status found that the intervention was more effective for more advantaged populations. Despite these rather sobering results, the authors come to the rather astonishing conclusion that, “Results from this review show promising evidence of the effectiveness of self-help interventions for weight loss.” and that, “Public health practitioners and policymakers should look to implement self-help interventions as a component of obesity intervention strategies because of the high reach and potentially low cost of these programs.” How exactly, the authors would come to these recommendations is unclear – my view would be that this could be a rather substantial waste of public… Read More »
FDA Approves VBLOC Treatment For Obesity
We don’t have great treatments for obesity, so every new evidence-based tool in the obesity treatment tool box is something to look at closely. The latest addition, just approved by the US FDA for the treatment of obesity in adults with a BMI of 40 to 45 kg/m2 or a BMI of 35 to 39.9 kg/m2 with a related health condition, is something I’ve posted about before – VBLOC or the vagal “pacemaker” as it is sometimes referred to. Indeed, Enteromedics‘ rechargeable Maestro system is very much like an implantable cardiac pacemaker, in that it delivers an electronic signal – in this case to block the action of the vagus nerve. The exact mode of action is not entirely clear but the weight-loss mediating effect (in the 10-15% average range) is largely a result of reduced appetite and increased satiety. Here is how Enteromedics describes its system: “The Maestro® System consists of a subcutaneously implanted rechargeable neuroregulator and two electrodes that are laparoscopically implanted by a bariatric surgeon. It delivers VBLOC® vagal blocking therapy via these electrodes that are placed in contact with the trunks of the vagus nerves just above the junction between the esophagus and the stomach. The device intermittently blocks vagal nerve signals throughout the patient’s waking hours. The Maestro System is recharged using an external mobile charger and transmit coil worn by the patient. The device can be non-invasively programmed, and it can be adjusted, deactivated, reactivated or completely removed if desired.” Obviously this is far from the be-all and end-all of obesity treatments – especially as it does not seem to work for everyone. Thus, the recently published results from the pivotal study (discussed here), was certainly far less impressive than the company may have hoped for. Just where VBLOC treatment will ultimately find its place in bariatric care remains to be seen – this is certainly a space to watch. @Dr. Sharma Edmonton, AB
Efficacy of Vagal Blockade For Obesity Treatment Remains Vague
Regular readers may recall past posts on the use of intermittent electrical blockade of the vagus nerves (VBLOC) as a means of reducing food intake to promote weight loss. Now a large randomised controlled study of vagal blocakade, published by Sayeed Ikramuddin and colleagues, published in JAMA, reports on rather disappointing outcomes with this treatment. In this study (ReCharge), conducted at one of 10 sites in the United States and Australia between May and December 2011, 239 participants with a BMI greater than 40 (or greater than 35 with at least one comorbidity), were randomised to receiving an active vagal nerve block device (EnteroMedics’ Maestro® Rechargeable (RC) System, n=162) or a sham device (n=77). Over the 12-month blinded portion of the 5-year study (completed in January 2013), the vagal nerve block group lost about 9% or their initial body weight compared to only 6% in the sham group. In addition to this rather modest difference in weight loss between the groups (about 3%), participants in the active treatment group also experienced a number of clinically relevant adverse effects (heartburn or dyspepsia and abdominal pain). Thus, overall these rather disappointing results are in line with the previously disappointing observations in the smaller MAESTRO trial. Based on these findings, it seems that intermittent electrical blockade of the vagal nerve may not hold its promise of a safe and effective long-term treatment for severe obesity after all. @DrSharma Edmonton, AB Ikramuddin S, Blackstone RP, Brancatisano A, Toouli J, Shah SN, Wolfe BM, Fujioka K, Maher JW, Swain J, Que FG, Morton JM, Leslie DB, Brancatisano R, Kow L, O’Rourke RW, Deveney C, Takata M, Miller CJ, Knudson MB, Tweden KS, Shikora SA, Sarr MG, & Billington CJ (2014). Effect of reversible intermittent intra-abdominal vagal nerve blockade on morbid obesity: the ReCharge randomized clinical trial. JAMA, 312 (9), 915-22 PMID: 25182100
Can Weight Loss Supplements Promote Weight Gain?
Apart from the fact that there are indeed no weight-loss supplements that will help you lose more than the weight of the money in your back pocket (a fact that even Dr. Oz had to admit to at a recent senate inquiry into the rubbish he promotes on his shows), there may be reason to suspect that the use of such supplements may in fact do the opposite. Thus, a rather simple experiment by Yevvon Chang and Wen-Bin Chiou from Tunghai University, Taichung, Taiwan, published in Nutrition, suggests that taking a (supposed) weight-loss supplement may actually lead to greater caloric intake. This field study was conducted in 70 volunteers, who were randomised to taking a either placebo or a weight-loss supplement (the same placebo) and were then exposed to a buffet meal. On average, participants presumably taking weight loss supplements ate a greater number of food items than did control subjects (overall about 30% more food). They also tended to chose less healthy items than the control group. This effect tended to be strongest in those subjects who had a more positive attitude towards taking supplements for weight loss (those with the most positive attitude eating almost 3 times more food items). Or, as the authors summarise, “…the results supported our hypothesis that taking weight loss supplements was associated with an inclination to eat more food. This link was driven by perceived progress toward the goal of weight reduction. The liberating effect of taking weight loss supplements on food consumption became more prominent as attitudes toward this kind of supplement became more positive.” Obviously, it is hard to extrapolate from such a short-term experiment to what happens over time – especially when people do follow the lifestyle recommendations that come with most supplements (eat-less-move-more). This study certainly is in line with the recent observation that people who take statins to lower their blood cholesterol levels tend to eat unhealthier diets and may in fact end up gaining more weight than people who don’t. Thus, it may be time to study the “fattening” effect of weight-loss supplements. Perhaps the only reason that we have not yet observed this effect in larger studies is because very few people stay on these nonsensical agents for more than a few weeks. @DrSharma Gambach, Germany Chang YY, & Chiou WB (2014). The liberating effect of weight loss supplements on dietary control: A field experiment. Nutrition… Read More »
Call For Abstracts: Canadian Obesity Summit, Toronto, April 28-May 2, 2015
Building on the resounding success of Kananaskis, Montreal and Vancouver, the biennial Canadian Obesity Summit is now setting its sights on Toronto. If you have a professional interest in obesity, it’s your #1 destination for learning, sharing and networking with experts from across Canada around the world. In 2015, the Canadian Obesity Network (CON-RCO) and the Canadian Association of Bariatric Physicians and Surgeons (CABPS) are combining resources to hold their scientific meetings under one roof. The 4th Canadian Obesity Summit (#COS2015) will provide the latest information on obesity research, prevention and management to scientists, health care practitioners, policy makers, partner organizations and industry stakeholders working to reduce the social, mental and physical burden of obesity on Canadians. The COS 2015 program will include plenary presentations, original scientific oral and poster presentations, interactive workshops and a large exhibit hall. Most importantly, COS 2015 will provide ample opportunity for networking and knowledge exchange for anyone with a professional interest in this field. Abstract submission is now open – click here Key Dates Notification of abstract review: January 8, 2015 Call for late breaking abstracts open: Jan 12-30, 2015 Notification of late breaking abstracts and handouts and slides due : Feb 27, 2015 Early registration deadline: March 3, 2015 For exhibitor and sponsorship information – click here To join the Canadian Obesity Network – click here I look forward to seeing you in Toronto next year! @DrSharma Montreal, QC
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