Program for Reducing Obesity (PRO): An institutional review of an insurance‐based weight loss program utilizing shared medical appointments

Abstract Background Based on CDC estimates in the United States, the prevalence of obesity was 42.4% in 2017–2018, and the annual cost of obesity was $147 billion in 2008. Yet studies estimate that only 20–40% of adults with obesity received counseling from their primary care providers. Recent studies using shared medical appointments (SMA), where patients are seen by a multidisciplinary team, have shown promising results in obesity management. We developed an insurance‐based weight loss program incorporating SMA, called the Program for Reducing Obesity (PRO), and report our findings here. Methods Enrollment began in January 2019 at the UCLA Health Thousand Oaks clinic. Patients age ≥18 years with BMI ≥30 kg/m2 were eligible by referral to PRO, a program consisting of individual visits and SMAs with an obesity medicine board certified endocrinologist and registered dietitian. Primary outcomes were change in weight after 3, 6, and 12 months. Secondary outcomes included proportion that achieved ≥5% weight loss, change in percent body fat, HbA1c, HDL, triglycerides, and blood pressure. Results 102 patients (mean age 59.7 years, 72% women, mean weight 103.6 kg, mean BMI 36.6 kg/m2) have been analyzed, with 91 patients completing at least 12 months of the program. Patients achieved significant weight loss: 3.0%, 5.0%, and 7.8% of their baseline weight after 3, 6, and 12 months respectively. 52% of patients lost ≥5% of their baseline weight after 12 months. Patients had significant reductions in body fat: 2.1%, 7.4%, and 6.7% of their baseline (all p ≤ 0.01) after 3, 6, and 12 months respectively. Improvements were also seen in HbA1c (p ≤ 0.01), triglycerides (p ≤ 0.04), and systolic blood pressure (p ≤ 0.07) after 12 months although not all results achieved statistical significance. Conclusion Our institutional review of PRO, an insurance‐based obesity program utilizing SMA, demonstrates a successful approach to promoting weight loss in a community‐based setting.

Internal Medicine, while endocrinology had the highest prevalence of prescribers of all subspecialties. 15 However this landscape may change with the recent availability of highly efficacious medications like the high dose semaglutide which has shown to result in as much as 16% weight loss compared to placebo. 16 More weight loss programs involving endocrinologists will likely improve utilization of AOMs as well.
In recent years, shared medical appointments (SMA) have emerged as a potential option for efficient delivery of obesity care.
SMAs allow patients sharing a common illness to convene as a group with one or more health care providers for education and counseling, clinical support, as well as individualized care including physical exam and medication management. 17 SMAs improve care delivery and outcomes for patients and providers through fostering camaraderie amongst patients, facilitating knowledge-sharing through peerto-peer interaction, and building equitable relationship and trust between patients and providers. 17 Utilization of SMA in obesity management has not been extensively studied. Previous studies show that patients attending SMAs were more likely to be prescribed anti-obesity medications 18 and to achieve sustained significant weight loss after 9 months, 19 12 months, 20 and 24 months. 18 SMAs were estimated to be four times more cost effective and seven times more time efficient than individual weight loss consultations. 20 In patients with prediabetes, the implementation of SMA led to a modest mean weight loss of 6.6 pounds at 1 year as well as a modest drop in fasting blood glucose of 6 mg/dL. 21 Of the previously mentioned studies, only Shibuya et al. focused on the impact of SMA programs led by endocrinologists. Given the significant overlap in disease burden of obesity and various endocrinopathies including diabetes, endocrinologists are well positioned to lead the effort to tackle the growing obesity pandemic. Here, we present our institutional findings of an insurance-based weight loss program called the Program for Reducing Obesity (PRO), which incorporates repeating cycles of SMA sessions led by a dietician and an endocrinologist who is also board-certified in obesity medicine.
Our data will augment the growing literature of SMA in the management of obesity.

| Study design and population
Patients age ≥18 years with body mass index (BMI) ≥30 kg/m 2 were eligible by referral from their UCLA primary care provider or endocrinologist to the Program for Reducing Obesity (PRO) at the UCLA Thousand Oaks clinic starting in January 2019. There were otherwise no explicit exclusion criteria. We analyzed the first 102 patients that were referred between January 2019 and August 2019. PRO continues to actively accept referrals for patients interested in joining the program. Thus, our cohort continues to grow beyond the initial 102 patients analyzed.
PRO is an insurance-based program consisting of individual visits and shared medical appointments (SMA) with an obesity medicine board certified endocrinologist and registered dietitian.

| Measures
Primary outcomes were absolute and percent change in weight and BMI after 3, 6, and 12 months from baseline. Baseline weight was defined as the weight measured at the initial visit for PRO. Subsequent weight measurements at 3, 6, and 12 months were obtained from either PRO appointments or at other UCLA clinic visits.
Secondary outcomes included proportion that achieved weight loss and ≥5% weight loss, change in percent body fat, hemoglobin A1c (HbA1c), high-density lipoprotein (HDL), triglycerides, systolic blood pressure (SBP), and diastolic blood pressure (DBP). Percent body fat was obtained using a Tanita segmental body composition analyzer. The Tanita segmental body composition analyzer uses bioelectric impedance to measure body composition.
Additional information, including age at start of program, race, ethnicity, number of visits with the obesity medicine board certified endocrinologist, number of nutrition classes attended, history of bariatric surgery, history of diabetes and prediabetes, and proportion that were prescribed weight loss medications were collected. Weight loss medications included the following: phentermine, topiramate, phentermine-topiramate, lorcaserin, naltrexone-bupropion, diethylpropion, and liraglutide. After lorcaserin was withdrawn from the market in February 2020, patients in the program that were prescribed lorcaserin were recommended to discontinue this medication.

| Statistical analysis
Descriptives for all variables were generated, and assessed for normality. Absolute and percent change in each variable relative to baseline were calculated for 3, 6, and 12 months. We used the paired t-test to compare two groups and ANOVA to compare more than two groups to determine whether change from baseline was significant at a two-sided alpha of 0.05. All statistical analyses were performed using STATA 14.

| Study participants
One hundred and two patients were analyzed in this report, with 91 patients completing at least 12 months of the program.
Demographics and baseline characteristics are shown in Table 1.
Most participants were female (72%) and Caucasian (80%). Mean age was 59.7 years with a mean weight of 103.6 kg, mean BMI of 36.6 kg/m 2 , and mean percent body fat of 42.6%. 70% of patients attended at least one nutrition class. 59% of patients were prescribed a weight loss medication during the program.

| Supplementary analysis
Supplementary analysis was performed to explore the change in BMI at 12 months from baseline, stratified by use of weight loss medications and weekly SMA group nutrition classes. There was a trend for greater reductions in BMI after 12 months in patients who both took weight loss medications and attended weekly SMAs, but the differences were not statistically significant (p ≤ 0.08, Table S1).
There was a trend showing greater reductions in BMI after 12 months for patients with a higher initial obesity class, however this was not statistically significant (data not shown).

| DISCUSSION
In our institutional review of an insurance-based obesity program utilizing SMA, we found statistically significant weight loss for patients after 3, 6, and 12 months. At 12 months, over half of the patients achieved at least 5% of weight loss compared to baseline weight. A 5% reduction in weight is clinically important due to associated improvements in multiple comorbidities, including prevention of diabetes, glycemic control in patients with diabetes, hyperlipidemia, hepatic steatosis, sleep apnea, knee pain, depression, sexual function, morbidity, and mortality. 22 Moreover, a reduction in BMI by 5%-10% has been associated with substantial savings in annual medical expenditures. 23 Our findings are consistent with prior studies implementing SMAs for weight management. 18 retrospective observational study following 222 patients who attended SMAs showed that 41% of patients achieved 5% weight loss at 9 months, with significant reductions in blood pressure and HbA1c. 19 We also demonstrate a concurrent reduction in body fat, which is an independent risk factor for metabolic dysfunction and obesity-related comorbidities. 25 There are limitations of our study. This study was non-controlled and retrospective in nature. Most participants in the program were female and Caucasian, and thus results may not be generalizable. SMAs, which may explain the higher percentage of weight loss seen here compared with other SMA studies. Furthermore, an insurancebased weight management program like PRO can serve as a costeffective model for community clinics to address the growing obesity epidemic. Future studies will explore whether the frequency of provider visits and weekly SMA group classes have an impact on the amount of weight change. We also plan to conduct an extension to our study to assess whether these patients are able to maintain weight loss in the long term.

| CONCLUSION
Our institutional review of PRO, an all insurance-based obesity program utilizing SMA demonstrates a successful approach to promoting weight loss in a community-based setting.