Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
Pfizer Incorporated, Cambridge, MA, USA.
Breast Cancer Res Treat. 2017 Oct;165(3):699-707. doi: 10.1007/s10549-017-4363-9. Epub 2017 Jul 4.
Research suggests that physical activity may be a promising treatment for cancer-related cognitive impairment; however, evidence is limited by small samples and self-report measures and little is known about the underlying mechanisms. The purpose of this study was to examine the effects of physical activity on cognitive function in a national sample of breast cancer survivors (BCSs) using objective measures. We hypothesized that physical activity's effects on cognition would be indirect through survivors' self-reported fatigue.
Participants (N = 299; M = 57.51 ± 9.54 years) included BCSs with access to an iPad. Participants wore an accelerometer for seven consecutive days to measure their average daily minutes of moderate-to-vigorous physical activity (MVPA) and completed a battery of questionnaires and neuropsychological tests via an iPad application to measure fatigue and cognitive function. Cognitive function was modeled as two latent factors-executive function and working memory-comprising performance across seven cognitive tasks. A structural equation modeling framework was used to test the hypotheses.
MVPA was associated with less fatigue (γ = 0.19), which, in turn, was associated with faster times on executive function tasks (γ = -0.18) and greater accuracy on working memory tasks (γ = 0.16). The indirect paths from MVPA to cognitive performance were also significant (executive function: β = -0.03, memory: β = 0.03).
Findings suggest that MVPA may be associated with greater executive function and working memory in BCSs. Further, this effect may be partially indirect through cancer-related symptoms (e.g., fatigue). Results emphasize the need for additional scientific investigation in the context of prospective and efficacy trials.
研究表明，身体活动可能是治疗癌症相关认知障碍的一种很有前途的方法；然而，由于样本量小和自我报告测量的限制，证据有限，并且对潜在机制知之甚少。本研究的目的是使用客观测量方法，在全国范围内的乳腺癌幸存者（BCS）样本中检查身体活动对认知功能的影响。我们假设，身体活动对认知的影响将通过幸存者自我报告的疲劳间接产生。
参与者（N=299；M=57.51±9.54 岁）包括可以使用 iPad 的 BCS。参与者佩戴加速度计连续七天，以测量其平均每天进行中度至剧烈身体活动（MVPA）的分钟数，并通过 iPad 应用程序完成一系列问卷和神经心理学测试，以测量疲劳和认知功能。认知功能被建模为两个潜在因素——执行功能和工作记忆——由七个认知任务的表现组成。使用结构方程模型框架来检验假设。
MVPA 与较少的疲劳相关（γ=0.19），而疲劳又与执行功能任务的完成时间更快相关（γ=-0.18），与工作记忆任务的准确性更高相关（γ=0.16）。MVPA 对认知表现的间接途径也具有统计学意义（执行功能：β=-0.03，记忆：β=0.03）。
研究结果表明，MVPA 可能与 BCS 更高的执行功能和工作记忆相关。此外，这种影响可能部分通过癌症相关症状（例如疲劳）间接产生。结果强调了在前瞻性和疗效试验背景下进一步进行科学研究的必要性。
