Trajectory of recurrent falls in post-menopausal breast cancer survivors and in matched cancer-free controls.

Abstract

Cross-sectional studies suggest that falls are prevalent among older breast cancer survivors. However, fall risk in this population has not been comprehensively examined. Therefore, we compared fall risk in older women post-breast cancer diagnosis to fall risk before cancer diagnosis and to risk in cancer-free matched controls. Among 2019 women in the Women's Health Initiative with localized breast cancer diagnosed at age ≥ 60years with fall assessment data for 3years pre-diagnosis and 3years post-diagnosis, recurrent fall risk post-diagnosis was compared to risk in 2019 cancer-free controls matched by age, year of WHI entry, and baseline fall frequency. Generalized estimating equations under a logistic regression model were used to compare fall recurrence in breast cancer survivors and controls. Multi-variable models were adjusted for the matching factors, race/ethnicity, body mass index, and multiple chronic conditions. In breast cancer survivors aged 70.8years (mean) at diagnosis, over the 3-year pre-diagnosis interval, recurrent falls were reported by 18.5%. Over the 3-year post-diagnosis interval, recurrent falls were reported by 21.8% of breast cancer survivors and 20.0% of controls over the same time period (P = 0.27). Recurrent fall risk did not differ between breast cancer survivors and control women (OR 1.07, 95% CI 0.92-1.25), even after multi-variable adjustment. In contrast to prior reports, older breast cancer survivors were not more likely to experience recurrent falls than age-matched counterparts. These findings underscore the need for incorporation of cancer-free control populations in survivorship studies to distinguish cancer sequelae from processes related to aging.