Self-reported side effects of breast cancer treatment: a cross-sectional study of incidence, associations, and the influence of exercise

Side effects as a result of breast cancer treatment may have a lasting detrimental impact on quality of life. Exercise has been shown to be an effective intervention in post-treatment care. This study aimed to gain a better understanding of breast cancer treatment-related side effects through identifying potential patient characteristic associations, including current levels of exercise. Four hundred and thirty-two breast cancer patients completed an online survey covering their treatment and demographic background, current exercise levels, and self-reported treatment side effects. Side effects were considered in a binary logistic regression against age, surgery, currently undergoing treatment, and exercise levels to ascertain significant relationships (p < 0.05) and associative values (Odds Ratio). Lumpectomy patients were less likely to report aching muscles (OR 0.61, 95 % CI 0.39-0.96), hot flushes (OR 0.60, 95 % CI 0.38-0.96), and weight gain (OR 0.59, 95 % CI 0.38-0.92) than mastectomy patients. Women currently undergoing treatment were more likely to report hot flushes (OR 3.77, 95 % CI 2.34-6.08), aching muscles (OR 1.62, 95 % CI 1.02-2.57), and weight gain (OR 1.89, 95 % CI 1.19-2.99) than women finished treatment. Sedentary women were more likely to experience shoulder limitations (OR 1.77, 95 % CI 1.14-2.77), muscular chest wall pain (OR 1.69, 95 % CI 1.07-2.65), weight gain (OR 2.29, 95 % CI 1.44-3.64), lymphedema (OR 1.68, 95 % CI 1.04-2.71), and breathlessness (OR 2.30 95 % CI 1.35-3.92) than their physically active counterparts. Patient characteristics may inform interventions to improve care post-breast cancer treatment. Sufficient levels of exercise were consistently associated fewer side effects and should be encouraged.