Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
Center on Aging and Health, Johns Hopkins University, Baltimore, Maryland.
Cancer. 2018 Dec 15;124(24):4692-4699. doi: 10.1002/cncr.31745. Epub 2018 Oct 1.
Using objectively collected physical activity (PA) data from the Baltimore Longitudinal Study of Aging, the authors tested whether patterns of daily activity and sedentary time differed by cancer survivorship in older adults.
In total, 659 participants (mean age ± standard deviation, 71 ± 10 years; 51% women) who had self-reported information on cancer history were instructed to wear an accelerometer for 7 consecutive days. Accelerometer data were summarized into: 1) PA volume and 2) activity fragmentation (interrupted activity), expressed as both continuous and as dichotomized (low and high) variables. Participants were categorized into 4 groups by cross-classification of dichotomous PA volume and fragmentation. Multiple regression models were used to estimate differences in PA patterns by cancer history.
Cancer survivors averaged 0.12 fewer log-transformed activity counts per day (standard error, 0.05; P = .02) than individuals who reported no history of cancer after adjusting for demographics, behavioral factors, and comorbidities. Although fragmentation did not differ by cancer survivorship in the continuous model (P = .13), cancer survivorship was associated with 77% greater odds (odds ratio, 1.77; 95% confidence interval, 1.11-2.82) of having high (vs low) fragmentation and 94% greater odds (odds ratio, 1.94; 95% confidence interval, 1.13-3.33) of having combined low PA/high fragmentation (vs high PA/low fragmentation) relative to those with no cancer history.
The current findings suggest that cancer survivors engage in lower total daily PA and that they perform this activity in a more fragmented manner compared with adults without a history of cancer. These results may reflect the onset and progression of a low-activity phenotype that is more vulnerable to heightened levels of fatigue and functional decline with aging.
本研究利用巴尔的摩老龄化纵向研究中客观收集的身体活动（PA）数据，检测癌症幸存者与老年人的日常活动和久坐时间模式是否存在差异。
共有 659 名参与者（平均年龄±标准差，71±10 岁；51%为女性）报告了癌症病史，并被要求佩戴加速度计连续 7 天。将加速度计数据总结为：1）PA 量，2）活动碎片化（中断活动），并以连续和二分变量（低和高）表示。通过对 PA 量和碎片化的二分变量进行交叉分类，将参与者分为 4 组。使用多元回归模型估计癌症病史对 PA 模式的差异。
在调整人口统计学、行为因素和合并症后，癌症幸存者每天的对数转换活动计数平均少 0.12（标准误差，0.05；P =.02）。尽管在连续模型中，碎片化与癌症生存状态无差异（P =.13），但癌症生存状态与高碎片化的可能性增加 77%（优势比，1.77；95%置信区间，1.11-2.82），与无癌症史者相比，低 PA/高碎片化（高 PA/低碎片化）的可能性增加 94%（优势比，1.94；95%置信区间，1.13-3.33）。
目前的研究结果表明，与没有癌症病史的成年人相比，癌症幸存者的日常总 PA 量较低，且活动更为碎片化。这些结果可能反映了低活动表型的发生和进展，这种表型更容易出现疲劳和功能衰退加剧的情况。
