Ms. Chatham is a 29-year-old woman who recently joined your practice; this is her second visit to your clinic. She made today’s appointment to discuss how she can lose weight and whether there are medications that she can take to aid in weight loss. She is relatively healthy, except for a history of childhood asthma. She says that she has been told indirectly, by her friends and family, that she is “overweight.” She has tried several popular diets without success; each time, she has lost 4.5 to 6.8 kg (10 to 15 lb) but has been unable to maintain the weight loss for more than a few months.
She does not have a history of coronary artery disease or diabetes. She has a regular menstrual cycle. She does not take any medications or nonprescription supplements. She does not smoke but does drink alcohol, occasionally as many as 4 or 5 drinks in a week, when she is out with friends. She tells you that she “watches what she puts in her mouth” and reads the nutritional labels on food packaging. However, she enjoys eating out and orders take-out meals 8 to 12 times a week.
She works as a computer programmer and spends most of her day sitting in an office. She belongs to a fitness club and tries to go there about once a week but notes that her attendance is inconsistent.
On physical examination, her vital signs are unremarkable except for a blood-pressure measurement of 144/81 mm Hg. She is 1.7 m (5 ft 7 in.) tall and weighs 92 kg (203 lb), and her body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) is 32. Her waist circumference is 94 cm (37 in.). There is no peripheral edema. The rest of the examination is unremarkable.
To aid in your decision making, each of these approaches is defended in a short essay by an expert in the field. Given your knowledge of the patient and the points made by the experts, which option would you choose? Factor into your decision the indications for pharmacologic therapies for weight loss, differences among the various weight-loss medications, concerns about their long-term efficacy and safety, and the role of adjuvant lifestyle and nonpharmacologic therapies in promoting and maintaining weight loss.
Ms. Chatham is a candidate for adjunctive pharmacotherapy in addition to lifestyle modification to assist in her weight management. The primary rationale for the use of weight-loss medications is to improve dietary adherence, which is one of the most important predictors of successful weight loss. Since the primary biologic effect of most weight-loss medications is reduced hunger, increased satiety, or both, the use of pharmacotherapy enables patients to adhere to a dietary plan that includes a reduction in calories and to do so with better control and a reduced sense of deprivation.[35 in.]
Weight-loss medications are approved for adults with a BMI of 30 or more, or 27 or more in the presence of at least one obesity-associated condition. Other factors to consider before prescribing a weight-loss drug include whether a patient has been unable to achieve or maintain a reasonable weight-loss goal or is unwilling to make a change in lifestyle behavior and whether the patient has realistic expectations of weight-loss medication use and related outcomes.
Four medications for weight loss have been approved by the Food and Drug Administration (FDA) since 2012 — phentermine–topiramate ER (extended release),2 lorcaserin,3 naltrexone–bupropion ER,4 and liraglutide.5 Orlistat, an intestinal lipase inhibitor that was approved in 1999, is the only other medication approved for long-term use. The efficacy and side-effect profiles of these medications, when used as adjuncts to lifestyle modification, have been established through prospective randomized, controlled trials that have had follow-up periods of 1 to 2 years.3,6 Although response rates vary among the studies, participants assigned to the medication groups achieved significantly greater weight loss than participants assigned to placebo, as well as improvements in cardiometabolic risk factors and quality of life. Among participants who completed 1 year of treatment, the average weight loss ranged from 7.0 to 12.4% among participants who received one of the four newer medications groups, as compared to 1.6 to 3.5% among those who received placebo.
Ms. Chatham presents with class I obesity (BMI of 30 to 34.9) and higher-risk upper-body fat distribution (waist circumference >89 cm [35 in.]). She also has elevated systolic blood pressure; since a weight loss of 5% or more has been shown to improve blood pressure, losing weight would benefit Ms. Chatham in this way as well. She has also noted difficulty in losing weight and maintaining weight loss and has expressed interest in considering weight-loss medication. After counseling her on the core principles of weight management, such as goal setting, building a plan for reduced caloric intake, increasing physical activity, reducing sedentary activity, and using self-monitoring strategies, I would broach the topic of weight-loss medication. The nature and incidence of side effects, along with cost, need to be considered when selecting among medications, a process that should be accomplished through shared decision making. A particular concern for Ms. Chatham is the need for birth control, because all weight-loss medications are contraindicated during pregnancy.
Once medication is initiated, Ms. Chatham should return to your clinic at least monthly for the first 3 months so that you can assess the efficacy and safety of the medication chosen, and at least every 3 months thereafter; more frequent counseling is associated with improved outcomes.[35 in.] Response to treatment (with a target weight loss of at least 3 to 5%, depending on the medication) should be determined after 3 to 4 months of use. If Ms. Chatham achieves this threshold, continued use is indicated, as long as she has no important adverse events and her course suggests that the medication is effective.