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Benefits of weight loss programs for breast cancer survivors: a systematic reviews and meta-analysis of randomized controlled trials

Abstract

Background

Obesity and weight gain have been associated with poor disease-specific and health-related outcomes in breast cancer survivors (BCS). But the benefits of weight loss in managing BCS have not been elucidated.

Objective

To evaluate the beneficial effects of weight loss programs in randomized controlled trials on BCS.

Methods

We searched English databases PubMed, the Cochrane Library, EMBASE, Scopus, Web of Science, CINAHL, and Chinese databases China National Knowledge Infrastructure (CNKI), Weipu Information Chinese Periodical Service Platform (VIP), China Biomedical Literature Service System (SinoMed), and Wanfang from the inception to January 2021 and collected randomized controlled trials (RCTs) of weight loss programs for BCS. Two reviewers independently screened the literature, extracted the data, and assessed the risk of bias in the included studies. The data synthesis was performed on RevMan (version 5.3), and the publication bias was calculated with STATA (version 15.1).

Results

Ten RCTs were included in the meta-analysis. The current study showed that diet and exercise interventions resulted in significant improvements in body weight (MD =  − 4.43 kg, 95%CI: − 6.23 to − 2.63, P < 0.00001), waist circumference (MD =  − 2.81 cm, 95%CI: − 4.37 to − 1.26, P = 0.004), hip circumference (MD =  − 3.01 cm, 95%CI: − 4.24 to − 1.77, P < 0.0001), body mass index (MD =  − 1.69 kg/m2, 95%CI: − 2.16 to − 1.21, P < 0.00001), systolic blood pressure (MD =  − 12.12 mmHg, 95%CI: − 18.97 to − 5.27), p = 0.0005), C-reactive protein (MD =  − 1.83 mg/L, 95% CI: − 2.74 to − 0.91, p < 0.0001), body fat (MD =  − 1.19 kg, 95%CI: − 1.75 to − 0.63, P < 0.001), fat mass (MD =  − 2.29 kg, 95%CI: − 3.12 to − 1.46, P < 0.0001), and lean body mass (MD =  − 2.15 kg, 95%CI: − 3.66 to − 0.65, P = 0.005). Alternatively, compared with the effects of control interventions, weight loss programs did not affect fat-free mass, total cholesterol, low-density leptin cholesterol, glucose, insulin, and leptin (P > 0.05).

Conclusions

This review summarizes the benefits of weight loss programs for BCS. The results indicated that weight loss programs could significantly improve specific anthropometric outcomes but not affect biochemical indicators. Researchers should tailor weight loss interventions to the body fat status of BCS. Evidence to support the translation of effective weight loss intervention programs into wider-scale implementation is needed to be part of routine survivorship care.

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Availability of data and materials

All data generated or analyzed during this study are included in this published article and its supplementary information files.

Abbreviations

BCS:

Breast cancer survivors

MD:

Mean difference

SMD:

Standardized mean difference

95% CI:

95% Confidence interval

RCTs:

Randomized controlled trials

BMI:

Body mass index

SBP:

Systolic blood pressure

CRP:

C-reactive protein

LDL-C:

Low-density leptin cholesterol

TC:

Total cholesterol

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Authors

Contributions

The conception and design of the review: Shurui Wang, Ting Yang, Wanmin Qiang, Zihan Zhao, Aomei Shen, Fangyuan Zhang.

Literature retrieval: Shurui Wang, Ting Yang.

Literature screening: Shurui Wang, Ting Yang, Zihan Zhao.

Quality assessment: Shurui Wang, Ting Yang, Zihan Zhao, Aomei Shen.

Data analysis: Shurui Wang, Wanmin Qiang, Aomei Shen, Fangyuan Zhang.

Writing – original draft: Shurui Wang.

Writing – review and editing: Shurui Wang, Ting Yang, Wanmin Qiang, Zihan Zhao, Aomei Shen, Fangyuan Zhang.

All authors read and approved the manuscript.

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Correspondence to Wanmin Qiang.

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Wang, S., Yang, T., Qiang, W. et al. Benefits of weight loss programs for breast cancer survivors: a systematic reviews and meta-analysis of randomized controlled trials. Support Care Cancer 30, 3745–3760 (2022). https://doi.org/10.1007/s00520-021-06739-z

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Keywords

  • Breast neoplasms
  • Diet
  • Exercise
  • Weight loss
  • Randomized controlled trials
  • Systematic review
  • Meta-analysis