Published Online:May 02, 2013
In the presentation “Overcoming Challenges in the Management of Obesity: A Closer Look at Emerging Therapeutic Options,” Trissa Reid, MD, an endocrinologist from the Columbia University Medical Center, reviewed the current concepts and practices around medical weight management.
The discussion opened up with the simple definition of obesity—which in many cases is not so simple since the standard calculation of body mass index (BMI) goes by an equation based just on weight and height. However, it is easily used in practice, with “overweight” defined as a patient with a BMI between 25.0 and 29.9, obese (2 levels) from 30.0 to 34.9 [level I] and from 35.0 to 39.9 [level II]. Morbid obesity is defined as a BMI greater than 40.
With the rising prevalence of obesity in the United States, in some cases doubling or tripling based a state-by-state basis, and the significant impact of obesity on almost organ system, Dr Reid noted that the management of obesity as a chronic disease is imperative. She noted that nonalcoholic fatty liver disease is the third most common indication for a liver transplant—a serious condition resulting in a marked clinical and economic burden.
Dr Reid guided the discussion towards the active management of obesity. Treatment options based on National Institutes of Health (NIH) guidelines lie in 3 areas: lifestyle changes (appropriate for all patients), drug therapy (indicated for patients with a BMI of >27 with comorbidities, >30 without), and bariatric surgery (indicated for patients with a BMI of >35 with comorbidities, >40 without). However, use of the adjustable gastric banding system has a US Food and Drug Administration (FDA) indication for patients with a BMI >30, but the procedure is not yet listed in the guidelines.
“The cornerstone for any effective weight management program is changing lifestyle.” This point, often repeated and emphasized by Dr Reid, needs to be used in conjunction with any other treatment options. Lifestyle modification includes behavior therapy (ie, self-monitoring, stimulus control, and stress management), diet (creating a caloric deficit), and exercise.
With respect to diets, Dr Reid reviewed a randomized controlled trial (RCT) using several different popular consumer systems. While there was modest weight loss associated with each system, there was weight gain when adherence to the diet dropped. In short, she said, “the best diet for a patient is the one they will stick to.”
On exercise, the recommendation is to start slow (30 minutes per day x 5 days per week) and increase to 60 to 90 minutes per day for most days of the week with strength training included at all stages. She noted that when approximately10% of body weight is lost, body metabolism will adjust and slow down. When that happens, additional exercise (or less caloric intake) is needed to continue to lose weight.
When it is time for pharmacologic intervention, it is recommended that before additional drugs are added, that a patient’s current drug regimen be evaluated. There are several drugs and drug classes associated with weight gain, such as some antidepressants, antipsychotics, antiepileptics, and even hypoglycemic agents. In many cases, there are alternatives that are “weight neutral” or even associated with weight loss that may be appropriate.
Current available products indicated for weight loss were described as short-term or long-term; the former used for less than 3 months, the latter for 1 year or longer. Dr Reid was cautious regarding the use of short-term agents, which included phentermine, phentermine resin, and diethylpropion because weight gain was observed after discontinuation of the products, and their use is indicated for a short time period. She reiterated her stance that obesity is a chronic disease and requires chronic care.
Long-term agents for management of obesity include orlistat (an intestinal lipase inhibitor), lorcaserin (a selective serotonin receptor agonist), and a combination product containing phentermine (a sympathomimetic stimulant) and topiramate (exact mechanism of action [MOA] for weight loss is unknown). Efficacy of each of these agents was reviewed with clinical trials reflecting notable weight loss (5% or 10%) at 1 year. In addition, the combination phentermine/topiramate product was associated with a delay in progression of type 2 diabetes.
Of note, lorcaserin, while approved by the FDA is not available until it receives a decision on its FDA schedule. The phentermine/topiramate combination, which up until recently was only distributed through a small number of distribution points will be available in community pharmacies in the next few months.
Regarding surgical options, Dr Reid reviewed the adjustable gastric band, the sleeve gastrectomy, and the Roux-En-Y gastric bypass. Each procedure was associated with significant weight loss of at least 50% to 70%, and in turn decreased weight-related complications such as hypertension, sleep apnea, disability, even resolution of type 2 diabetes in many cases. However, she noted that weight gain after these procedures is very possible for many patients, and lifestyle modification, if not pharmacotherapy, may be required.
In summary, Dr Reid emphasized that obesity management should be a stepwise approach, directed towards long-term treatment using realistic goals, but always with lifestyle modification in mind.