New Evidence and Policy Support Primary Care–Based Weight Loss Interventions

Obesity has become ubiquitous in the primary care setting. More than one-third of adults in the United States are obese, and prevalence of obesity is even higher among those with chronic conditions such as cardiovascular disease and diabetes.¹ Obesity adversely affects blood pressure, lipid profile, and diabetes, all major cardiovascular risk factors. As a consequence, obese individuals have increased risk of death, especially from cardiovascular disease.² The US Preventive Services Task Force³ recommends screening of all adult patients for obesity and offering intensive, behavioral counseling to promote sustained weight loss for obese adults. However, recent data indicate that less than half of primary care physicians record body mass index (BMI) regularly or provide specific guidance on diet, physical activity, or weight control; about one-fifth systematically track weight or weight-related behaviors; and less than 10% refer patients for further evaluation or weight management.⁴ The barriers to treating obesity in the primary care setting are numerous and include inadequate guidance on how to provide effective behavioral weight loss counseling.^3,5,6 Two recent trials of weight loss interventions delivered in primary care settings to obese patients with cardiovascular risk factors over 2 years provide evidence that begins to bridge this gap.^7,8 Inadequate reimbursement for weight loss counseling is another long-standing barrier to obesity treatment in primary care settings. However, in late November 2011, the Centers for Medicare and Medicaid Services (CMS) announced that it will cover obesity screening and counseling as a preventive service under Medicare.⁹ New evidence supporting the effectiveness of weight loss counseling strategies in conjunction with CMS reimbursement for these services offers potential to dramatically increase the number of individuals who receive screening and treatment for obesity in primary care.

In the first trial, Appel et al⁷ randomly assigned 415 obese adults with at least 1 cardiovascular risk factor from 6 primary care practices to 1 of the following groups: (1) control group—self-directed weight loss program; (2) remote support group—commercial call center–based lifestyle coaches remotely delivered all lifestyle interventions by telephone, Internet, and e-mail; or (3) in-person support group—in-person support with individual sessions plus group sessions, along with the 3 remote means of support (ie, electronic and telephone contacts) delivered by clinic-based lifestyle coaches.⁷ Primary care providers (PCPs) supported intervention delivery; they used an intervention progress report at routine visits to provide basic weight loss guidance and motivate their patients. Weight loss at 2 years was similar in the groups that received in-person support (5.1 kg) and remote support (4.5 kg) and was significantly greater than the weight loss in the control group (0.8 kg). Participants assigned to either the in-person or the remote lifestyle intervention were twice as likely as those assigned to the control group to have lost 5% or more of their initial body weight at 2 years (41% for the in-person group and 38% for the remote group vs 19% for the control group).

Importantly, this intervention was based on social cognitive theory and incorporated behavioral self-management approaches designed to help participants set weight-related goals, self-monitor weight and weight-related behaviors (exercise and reduced calorie intake), increase self-efficacy and social support, and solve problems.⁷ Motivational interviewing was the primary approach to interactions with participants. Weight loss coaches encouraged participants to complete learning modules and provided positive reinforcement of key behaviors, with an emphasis on self-monitoring of weight, calorie intake, and exercise. Participants in the 2 intervention groups were encouraged to lose 5% of their baseline weight within 6 months and to maintain the reduced weight until the end of the study. Coach training covered behavioral theory and strategies, basic nutritional and exercise guidelines, and motivational interviewing techniques.

In the second trial, Wadden et al⁸ randomized 390 obese adults with at least 2 of 5 components of the metabolic syndrome from 6 primary care practices to 1 of the following groups: (1) usual care (UC)—5 to 7 minutes of counseling provided by the PCP at quarterly PCP office visits, (2) brief lifestyle counseling (BLC)—monthly 15-minute, in-person counseling visits with lifestyle coach (trained medical assistants), or (3) enhanced lifestyle counseling (ELC)—BLC plus a toolbox that included meal replacements and weight loss medications. All participants were prescribed the same goals with respect to diet and physical activity but were provided with different levels of support to achieve them. Participants whose weight was less than 113.4 kg were prescribed a balanced diet of 1200 to 1500 kcal/d (1500–1800 kcal/d for participants who weighed ≥113.4 kg), which consisted of 15% to 20% kcal from protein, 20% to 35% kcal from fat, and the remainder from carbohydrate. All participants were instructed to gradually increase their physical activity to 180 min/wk and were given a pedometer, a calorie counting book, and handouts from Aim for a Healthy Weight. The BLC participants were scheduled for the same quarterly PCP visits as the UC group but also spent 10 to 15 minutes each month with a lifestyle coach, who delivered obesity counseling (weigh-in, review of participants’ recording of food/calorie intake, physical activity, and other goals). The ELC participants received the same PCP and lifestyle coach counseling visits as those assigned to BLC. However, in consultation with their PCP, they also chose to take sibutramine 10 to 15 mg, orlistat 60 to 120 mg, or meal replacements (shakes or meal bars) to increase weight loss, beginning 1 month after treatment began. (Participants were allowed to choose among these options). After sibutramine was removed from the market, participants who took this medication switched to either meal replacements or orlistat. Initial weight decreased at least 5% over 2 years in 22%, 26%, and 35% of the participants in the 3 groups, respectively. Patients in the ELC group lost significantly more weight (4.6 kg) than did those in either the BLC (2.9 kg) or UC (1.7 kg) groups and were more likely to lose at least 5% of their initial body weight (35% in ELC versus 26% in BLC and 22% in UC).

Concurrent with the release of these trials, in an important step toward addressing the obesity epidemic, the CMS announced that it will now cover obesity screening and intensive behavioral counseling as a preventive service under Medicare.⁹ However, this benefit is limited to primary care practitioners (defined as physician, nurse practitioner, clinical nurse specialist, or physician assistant) and primary care settings. Specific services reimbursable under Medicare include an obesity screening, an assessment of the patient’s diet, and behavioral counseling and therapy to promote sustained weight loss through diet and exercise. The services will be free to beneficiaries—the Medicare deductible and copay will not apply. This course of treatment does not include medications for losing weight. The CMS coverage of intensive behavioral counseling for obesity is summarized in the Box.

Box: Summary of Centers for Medicare & Medicaid Services Coverage of Intensive Behavioral Counseling for Obesity as a Preventive Service⁹

The trials reported by Appel et al⁷ and Wadden et al⁸ provide evidence that safe and effective weight loss interventions can be delivered in primary care settings. However, both trials provided treatments at no cost to the participants. Although the CMS has recently initiated reimbursement for intensive behavioral counseling for obesity, CMS’s definition of “primary care practitioners” who are eligible for reimbursement is extremely limited. In addition, medications or meal replacements for weight loss, as delivered by Wadden et al,⁸ are not covered. Whether patients would be willing to pay for these therapies or other insurers would be willing to reimburse for them is not known.¹⁰

Sustainability of behavioral interventions is challenging, with attendance at in-person counseling sessions decreasing substantially over time.¹⁰ In both trials, attendance at in-person sessions was less than 50%. However, Appel et al⁷ reported higher participation with remote counseling. Given that remotely delivered counseling resulted in weight loss outcomes similar to those of in-person visits, the use of mobile technologies to deliver behavioral weight loss treatment in primary care appears to be promising.¹⁰ Such interventions may present fewer barriers to adherence than interventions delivered in person because they allow for greater scheduling flexibility, decreased travel time, and lower transportation costs. In addition, a telephone-based counseling program has the potential for widespread implementation in multiple practice settings, including geographically isolated areas.¹⁰ However, it is not clear whether the CMS will provide full coverage of remote counseling programs.

The CMS’s new coverage of weight loss behavioral counseling is a step in the right direction to support the adoption of effective behavioral counseling strategies in primary care practice. However, expanded coverage to include remote counseling programs and effective behavioral counselors such as dieticians and health educators is needed.

Cardiovascular nurses in primary care settings have an opportunity to take a leading role in treating obesity, although current CMS coverage for behavioral counseling is limited to nurse practitioners and clinical nurse specialists. In addition to counseling patients, highly skilled nurses can train other members of the primary care team in behavioral counseling approaches and motivational interviewing techniques and establish systems (eg, remote counseling programs) to help obese patients achieve their weight loss goals.¹¹