(P25-069-20) Effect of Lifestyle Intervention Programs on Weight-Loss and Maintenance in Obese Adults: A Systematic Review with Meta-Analysis and Trial Sequential Analysis

Objectives: To evaluate the effect of lifestyle change programs on weight-loss and its maintenance in obese individuals. The trial sequential analysis (TSA) was applied to determine whether the currently available evidence is sufficient.

Methods: The PubMed, EMBASE and Lilacs databases were searched for randomized clinical trials published before May of 2018. Data were pooled using an inverse-variance random-effects meta-analysis and expressed as weighted mean differences (WMD) with 95% confidence intervals (CI). Heterogeneity was quantified and explored using subgroup analyses.

Results: Eleven trials (12 publications, 1416 participants) were considered eligible to be included in this meta-analysis. Caloric restriction was effective to promote weight-loss at 12 months [WMD −3.79kg (95%CI −4.78 to −2.79), I²=87.5%] and 24 months [WMD −6.20kg (95%CI −10.81 to −1.59), I²=71.2%] and TSA showed convincing evidence of an effect. At 36 months, there were no differences in body weight change [−2.06kg (95%CI −7.00 to 2.89), I²=0.0%] and the meta-analysis included less patients than the required information size according to TSA. Subgroup analyses suggest improved weight-loss for caloric restrictions that are greater than 501 Kcal, Dietitian as the interventionist, intensity of intervention twice a month and dropout rates of < 20%.

Conclusions: For obesity management in clinical practice, caloric restriction is effective to promote weight-loss for up to two years, preferably with a caloric deficit that is greater than 501 Kcal, if performed by registered Dietitian and if associated with a behavioral component and at least twice-monthly contact with a health team. For weight-loss maintenance greater than three years, large-scale trials are required to support these findings.

Funding Sources: This systematic review was supported by Fundo de Incentivo à Pesquisa e Eventos (FIPE) from Hospital de Clínicas de Porto Alegre. JPP was recipient of scholarships from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).