Weight loss in primary care: A pooled analysis of two pragmatic cluster-randomized trials

Abstract

Objective: The aim of this study was to report the results of five weight-loss interventions in primary care settings in underserved patients and to compare the level of pragmatism across the interventions using the Pragmatic Explanatory Continuum Indicator Summary (PRECIS-2) tool.

Methods: Data from 54 primary care clinics (2,210 patients) were pooled from the Promoting Successful Weight Loss in Primary Care in Louisiana (PROPEL) and Rural Engagement in Primary Care for Optimizing Weight Reduction (REPOWER) cluster-randomized trials. Clinics were randomized to one of five comparators: PROPEL usual care, PROPEL combination of in-clinic and telephone visits, REPOWER in-clinic individual visits, REPOWER in-clinic group visits, or REPOWER telephone group visits.

Results: At 24 months, weight loss (kilograms) was -0.50 (95% CI: -1.77 to 0.76), -3.05 (-4.10 to -2.01), -4.30 (-5.35 to -3.26), -4.79 (-5.83 to -3.75), and -4.80 (-5.96 to -3.64) in the PROPEL usual care, REPOWER in-clinic individual visits, REPOWER telephone group visits, REPOWER in-clinic group visits, and PROPEL in-clinic and telephone visits arms, respectively. At 24 months, percentage of weight loss was -0.360 (-1.60 to 0.88), -3.00 (-4.02 to -1.98), -4.23 (-5.25 to -3.20), -4.67 (-5.69 to -3.65), and -4.69 (-5.82 to -3.56), respectively, in the five arms. The REPOWER in-clinic individual visits intervention was the most pragmatic and reflects the current Centers for Medicare and Medicaid Services funding model, although this intervention produced the least weight loss.

Conclusions: Clinically significant weight loss over 6 months in primary care settings is achievable using a variety of lifestyle-based treatment approaches. Longer-term weight-loss maintenance is more difficult to achieve.

Trial registration: ClinicalTrials.gov NCT02561221 NCT02456636.

Conflict of interest statement

CONFLICT OF INTEREST

PTK, JWA, CKM, RLN, and WDJ report donated supplies from Health and Nutrition Technology and Nutrisystem for the Promoting Successful Weight Loss in Primary Care in Louisiana (PROPEL) trial. MGP reports additional grant funding from NIH and chairing the Data and Safety Monitoring Board (DSMB) for the PCORI-funded Treatment Efforts Addressing Child Weight Management by Unifying Patients, Parents & Providers (TEAM-UP) trial. CKM additionally reports payments to his university for projects funded by Westat, WW (formerly WeightWatchers), the Egg Board, the Academy of Nutrition and Dietetics, Eli Lilly and Company, American Society for Nutrition, Helmsley Trust, Richard King Mellon Foundation, Evidation Health, Individuals Dedicated to Excellence and Achievement (IDEA) Public Schools, LiftFund Louisiana, Elizabeth Blackwell Institute for Health Research, and Novartis International AG. CKM further reports that ABGIL has provided grants to his institution and he was an investigator on those grants. This work is related to interventions that utilize weight graphs to track dietary adherence. CKM reports having received royalties from his institution for the licensing of weight-management approaches and weight-graphing algorithms. CKM reports serving on an advisory board for Naturally Slim and EHE Health and serving as a consultant for Zafgen; Florida Hospital; Metagenics, Inc.; and Gila Therapeutics, Inc. CKM is a facilitator for continuing education events hosted by the Academy of Nutrition and Dietetics. CKM regularly gives talks, both paid and unpaid, primarily to academic centers, including Robert Wood Johnson Foundation, Association for the Study of Obesity, American Society for Metabolic and Bariatric Surgery (ASMBS), Institute of Electrical and Electronics Engineers (IEEE), and American Association of Clinical Endocrinologists. CKM reports having received reimbursement for travel expenses from the the Academy of Nutrition and Dietetics, Association for Community Affiliated Plans Health/Naturally Slim, EHE Health, Aaptiv, the Obesity Society/IEEE, and the American Association of Clinical Endocrinologists. CKM reports United States and European Patent applications titled “Body weight management and activity tracking system.” The other authors declared no conflict of interest.

© 2021 The Obesity Society.

Figures

FIGURE 1

Participant flow through the PROPEL and REPOWER trials. *Patients who became pregnant, had bariatric surgery, or developed a major illness and/or died were removed from the REPOWER trial a priori; patients who became pregnant, had bariatric surgery, or developed a major illness and/or died were retained in the PROPEL trial, and their data were removed beyond the time the event occurred. PROPEL, Promoting Successful Weight Loss in Primary Care in Louisiana trial; REPOWER, the Rural Engagement in Primary Care for Optimizing Weight Reduction trial

FIGURE 2

Changes in (A) percent weight loss (percentage) and (B) absolute weight loss (kilograms) in the pooled analysis of data from the PROPEL and REPOWER trials. PROPEL, Promoting Successful Weight Loss in Primary Care in Louisiana trial; REPOWER, the Rural Engagement in Primary Care for Optimizing Weight Reduction trial; UC, usual care