Exercise for improving bone health in women treated for stages I-III breast cancer: a systematic review and meta-analyses.

PURPOSE: The purpose of this study was to evaluate the efficacy of exercise, either alone or in combination with other interventions, compared to a control, for the preservation of bone mineral density (BMD) in early breast cancer (BC) patients.

METHODS: A systematic search was conducted to identify randomized or quasi-randomized trials which met inclusion criteria including prescribed exercise for ≥12 months. Ten publications from seven randomized controlled trials (RCTs), involving 1199 participants, were identified. Data on primary and secondary outcome measures related to BMD at the lumbar spine, total hip, femoral neck and greater trochanter were analysed. Meta-analyses were limited to subgroups by menopausal status as other data could not be pooled.

RESULTS: Based on mean differences or mean percentage differences between groups at 1 year, exercise did not preserve BMD or bone mineral content at any site in post-menopausal women. In contrast, evidence from one RCT (n = 498) found that exercise reduced bone loss in pre-menopausal women at the femoral neck [% MD = 1.20 (95% CI 0.22-2.18); P = 0.02] but not at the lumbar spine.

CONCLUSIONS: Although this review indicated that exercise may result in a clinically important preservation of bone health among pre-menopausal but not post-menopausal women, further studies are needed to confirm whether or not exercise is important in preservation of bone health in women diagnosed with early BC.

IMPLICATIONS FOR CANCER SURVIVORS: Exercise alone may not be sufficient to prevent bone loss in post-menopausal women at high risk of osteoporosis. Further evidence is required to determine if it provides any benefit to pharmacological therapy.