CARDIORESPIRATORY FITNESS BENEFITS VERBAL MEMORY IN OLDER BUT NOT YOUNGER BREAST CANCER PATIENTS

摘要

Breast cancer survivors often experience cognitive problems following surgery and prior to further treatment. Cardiorespiratory fitness (CRF) benefits cognitive function in healthy older adults. However, few studies address CRF’s effects among breast cancer survivors or consider how this pattern may vary by age. As part of a larger study, 110 female post-surgical breast cancer survivors (ages 26 to 75, stages I-IIIA) completed a graded cycle ergometry test to measure peak oxygen consumption prior to chemotherapy or radiation treatment. Neuropsychological tasks assessed verbal memory (Hopkins Verbal Learning Test), verbal fluency (F-A-S), executive function (Trail Making Test, n-back task), and sustained attention (Continuous Performance Test). Regression models revealed that the relationship between CRF and immediate verbal recall scores varied significantly by age, above and beyond education, comorbidities, cancer stage, and time since surgery (b = .013, SE = .006, p = .032). Among women ages 62 and older, those with better fitness had better immediate verbal recall compared to those with poorer fitness, using the Johnson-Neyman method. The age by CRF interaction did not significantly predict performance on other cognitive tasks in adjusted models. Accordingly, older participants who were more fit had better immediate verbal recall than those who were less fit, while younger women’s CRF was not significantly related to their verbal memory performance. The fitness-cognitive function link may be particularly relevant for older cancer survivors compared to their younger counterparts. Longitudinal studies would help discern if physical fitness prevents accelerated cognitive aging among cancer survivors, and prompt relevant interventions.