Effects of aquatic exercises in woman who have undergone surgery after breast cancer: a systematic review with meta-analysis

Background: Breast cancer (BC) is the most common cancer among women, with an incidence of 310,720 new cases for the year 2024. In addition to survival, quality of life has become an important outcome measure in BC clinical investigations. Objective: To evaluate the effects of aquatic exercises (AE) on quality of life (QoL), lymphedema, pain, fatigue, and range of motion in breast cancer survivors compared to land exercise and a control group. Design: Systematic review. Ten databases were searched from inception until February 2024. Risk of bias and certainty of evidence were assessed using the Risk of Bias 2 tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Pooled effects were calculated using standardized mean difference (SMD) and 95 % confidence interval (CI). Results: A total of 1873 studies were identified, 10 were included in the review and four were included in a meta-analyses. Only 30 % (n = 3) of the studies were classified as having a low risk of bias. The effect of AE on the emotional subdomains of the QoL was superior to usual care (SMD=0.58; 95 % CI: 0.1, 0.9; I²=0 %) but the certainty of evidence was rated as very low. When AE was compared with land exercise, no significant differences were found for pain (SMD=1.1; 95 % CI: 1.5, 3.7; I²=97 %) with the certainty of evidence graded as low. Conclusions: Although further studies of high methodological quality are needed to provide more robust conclusions, AE may improve QoL outcome and emotional subdomain compared to usual care, but the evidence is very uncertain.