Aline Marcadenti^1-3*, Nathalia Sernizon Guimarães^4*, Gustavo Waclawovsky², Eman Youssif^5-7, Marcela Gomes Reis^4, Renato Hideo N. Santos¹, Andréia Guaragni Severgnini², Annette Garcia⁸, Bianca Rodrigues dos Santos¹, Camila Weschenfelder⁹, Dania Alkhiyami¹⁰, Diego Silveira da Silva², Erica Aranha Suzumura¹¹, Erlon O de Abreu-Silva^1,12, Flavia Barbosa Leite e Silva², Flavia Kojima¹, Graziela Biude Silva Duarte¹³, Isabel Hernández Linares1⁴, Jackeline Gomes¹, João Gabriel Sanchez¹, Juan Carlos Silva Godínez^{15, Lizandra Traldi Mendonça Sanches16, Lucas Ribeiro da Silva1, Lucas Petri Damiani1, Lucas Tramujas1, Mabel F Figueiro1, Marcondes Silva17, Maria Inês Gonzalez Solari2, Marina Lazzari Nicola1, Maria S Simon18, Pedro Gabriel Melo de Barros e Silva1, Pedro Nascimento Martins19, Rachel Helena V Machado1, Rafael Longhi4, Raquel Quimas Molina da Costa20, Salim H. Al-Busaidi21, Samara P Mendrico1, Victor Andrade Batistella22,23, Diego Arbaje24, Alexandre Biasi1, Ângela Cristine Bersch-Ferreira1,25}

¹Hcor Research Institute (IP-Hcor), Associação Beneficiente Síria, São Paulo, Brazil

*Corresponding Author: Aline Marcadenti, Hcor Research Institute (IP-Hcor), Associação Beneficiente Síria and Graduate Program in Health Sciences (Cardiology), Instituto de Cardiologia/Fundação Universitária de Cardiologia do Rio Grande do Sul (IC/FUC), Porto Alegre and Graduate Program in Epidemiology, Faculdade de Saúde Pública da Universidade de São Paulo (FSP-USP), São Paulo, Brazil.

Received: August 07, 2025; Published: September 05, 2025

Abstract

Nutrition-based lifestyle changes are primary component of obesity treatment, yet they are challenging to sustain. Although randomized clinical trials (RCTs) support the effect of dietary interventions for weight loss, long-term follow-up remains difficult due to high attrition rates. Nutrition-related interventions require substantial commitment and lifestyle modifications, which may contribute to higher dropout rates compared to pharmacological trials that offer weight loss with fewer behavioral changes. This study presents the protocol for a systematic review aiming to compare loss to follow-up rates in RCTs evaluating nutritional versus pharmacological interventions for weight loss in adults with overweight or obesity. The review will be conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Eligible studies will include RCTs comparing dietary and pharmacological strategies for weight reduction, specifically reporting loss to follow-up rates. Studies will be identified through comprehensive searches of PubMed, Embase, LILACS, Cochrane Central Register of Controlled Trials, Web of Science, and CINAHL databases without language or temporal restrictions. Data extraction and quality assessment will be performed. Results will be synthesized to compare attrition rates between intervention types. As this study involves secondary analysis of published data, ethical approval is not required. The findings will be disseminated through peer-reviewed publications, conference presentations, and clinical and academic networks, providing insights into participant retention challenges in weight loss trials and informing future clinical guidelines for obesity management.

Keywords: Weight Loss; Randomized Controlled Trials; Nutrition Intervention; Pharmacological Treatment; Attrition Rate; Systematic Review

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Citation

Citation: Aline Marcadenti., et al. “Comparison of Loss to Follow-Up Rates in Randomized Clinical Trials of Nutritional Versus Pharmacological Interventions for Weight Reduction: A Systematic Review Protocol".Acta Scientific Nutritional Health 9.10 (2025): 03-17.

Copyright

Copyright: © 2025 Aline Marcadenti., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.