Efficacy of lifestyle weight loss interventions on regression to normoglycemia and progression to type 2 diabetes in individuals with prediabetes: a systematic review and pairwise and dose-response meta-analyses.

Background: Current recommendations for weight loss in individuals with prediabetes come from individual trials and are derived from older data.
Objective: To elucidate the dose-dependent impacts of weight loss on participants with prediabetes to determine the optimal magnitude of weight loss required for the implementation of the most effective diabetes prevention program.
Methods: We searched PubMed, Scopus, CENTRAL, CINAHL, and grey literature sources to September 2023 for randomized trials ≥6 months that evaluated the efficacy of a lifestyle weight loss intervention on participants with prediabetes. We conducted random-effects pairwise meta-analyses to calculate relative and absolute effects. We performed one-stage weighted mixed-effects meta-analysis to elucidate the dose-response curves.
Results: 44 randomized trials with 14,742 participants with prediabetes (intervention duration range: 6 to 72 months [median=24 months], average weight loss range: 1% to 9%) were included. Lifestyle weight loss interventions increased regression to normoglycemia by 11 per 100 participants (95%CI: 8 more, 17 more; risk ratio: 1.51, 95%CI: 1.27, 1.80; n=20 trials, GRADE=moderate), and reduced progression to type 2 diabetes by 8 per 100 participants (95%CI: 11 fewer, 6 fewer; risk ratio: 0.59, 95%CI: 0.51, 0.67; n=37, GRADE=moderate). There were no significant or credible differences among subgroups categorized by the type and duration of intervention. Dose-response meta-analyses indicated that the risk of regression to normoglycemia increased and the risk of progression to type 2 diabetes declined in a linear pattern within the range of weight loss from 1% to 9%.
Conclusions: Over a median duration of 24 months, with weight loss ranging from 1% to 9%, the relationship between weight loss and the progression to type 2 diabetes, as well as the regression to normoglycemia, follows a linear pattern. Any form of lifestyle weight loss interventions including diet, exercise, or a combination of both, can have beneficial impacts on participants with prediabetes.
Protocol Registration: PROSPERO (CRD42023465322).
(Copyright © 2024 American Society for Nutrition. Published by Elsevier Inc. All rights reserved.)