Chawla Harsh, Bulathsinghala Chinthaka, Tejada John Patrick, Wakefield Dorothy, ZuWallack Richard
1 Division of Pulmonary and Critical Care Medicine, Department of Medicine.
Ann Am Thorac Soc. 2014 Oct;11(8):1203-9. doi: 10.1513/AnnalsATS.201405-198OC.
Because physical inactivity in chronic obstructive pulmonary disease (COPD) predicts health care use and mortality, we prospectively evaluated the relationship of this variable to the frequency of 30-day readmissions after a hospitalization for an exacerbation.
Consented patients discharged after an exacerbation of COPD were asked to wear a GT3X+ accelerometer (ActiGraph, Pensacola, FL) continuously on the wrist for 30 days after hospital discharge. Vector magnitude units (VMU), the sum of movements in three planes over each minute of use, were recorded. Higher physical activity for each minute was defined by a VMU threshold of at least 3,000 counts. Those patients with fewer than 60 minutes/day over the first week were considered inactive.
Fifty-four study patients were discharged from the hospital and 38 underwent activity testing. In the latter subgroup, all-cause hospital readmissions within 30 days occurred in 12 patients (32%). Minutes of higher physical activity per day over the first week after discharge were considerably lower in those eventually readmitted than in those who remained as outpatients: 42 ± 14 (SE) versus 114 ± 19 minutes, respectively (P = 0.02). In addition, physical activity decreased over time in those who were eventually readmitted, but increased in those who were not readmitted. Those with lower physical activity over Week 1 after discharge were more likely to have 30-day all-cause readmissions than those with higher activity: odds ratio, 6.7, P = 0.02. In multivariate testing, both physical inactivity and a history of two or more hospitalizations for exacerbations in the preceding year predicted 30-day readmission.
These findings underscore the importance of physical activity as a predictor of this type of health care use outcome.
由于慢性阻塞性肺疾病（COPD）患者缺乏身体活动可预测医疗保健利用情况和死亡率，我们前瞻性地评估了这一变量与因病情加重住院后30天再入院频率之间的关系。
COPD病情加重后出院且签署知情同意书的患者，在出院后需连续30天在手腕上佩戴GT3X +加速度计（美国佛罗里达州彭萨科拉市ActiGraph公司）。记录向量大小单位（VMU），即每分钟使用过程中三个平面运动的总和。每分钟身体活动量较高定义为VMU阈值至少为3000计数。第一周每天活动时间少于60分钟的患者被视为缺乏身体活动。
54例研究患者出院，38例接受了活动测试。在后一亚组中，12例患者（32%）在30天内发生了全因再次入院。出院后第一周，最终再次入院患者每天较高身体活动的分钟数明显低于仍为门诊患者的患者：分别为42±14（标准误）分钟和114±19分钟（P = 0.02）。此外时，最终再次入院患者的身体活动随时间减少，而未再次入院患者的身体活动则增加。出院后第一周身体活动较少的患者比活动较多的患者更有可能在30天内发生全因再次入院：比值比为6.7，P = 0.02。在多变量测试中，缺乏身体活动和前一年因病情加重住院两次或更多次的病史均预测了30天再入院情况。
这些发现强调了身体活动作为此类医疗保健利用结果预测指标的重要性。
