Background

Physical capacity (PC; “can do”) and physical activity (PA; “do do”) are prognostic indicators in COPD and can be used to subdivide patients with COPD into four exclusive subgroups (the so-called “can do, do do” quadrants). This concept may be useful to understand better the impact of PC and PA on all-cause mortality in patients with COPD.

Research Question

What is the 6-year all-cause mortality risk of the “can do, do do” quadrants of patients with COPD?

Study Design and Methods

This retrospective study used data from patients with COPD who underwent a comprehensive assessment at their first-ever outpatient consultation. PC was assessed using the 6-min walk distance and physical activity was assessed using an accelerometer (steps per day). All-cause mortality data were obtained from the Municipal Personal Records Database. Receiver operating characteristic curves were used to determine threshold values for PC and PA to predict 6-year all-cause mortality. Using the derived threshold values, male and female patients were divided into the four “can do, do do” quadrants.

Results

Data from 829 patients were used for analyses. Best discriminatory values for 6-year mortality were 404 m and 4,125 steps/day for men and 394 m and 4,005 steps/day for women. During a median follow-up of 55 months (interquartile range, 37-71 months), 129 patients (15.6%) died. After controlling for established prognostic factors, patients in the “can do, don’t do” quadrant and “can do, do do” quadrant showed significantly lower mortality risk compared with patients in the “can’t do, don’t do” quadrant: hazard ratios of 0.36 (95% CI, 0.14-0.93) and 0.24 (95% CI, 0.09-0.61) for men and 0.37 (95% CI, 0.38-0.99) and 0.29 (95% CI, 0.10-0.87) for women, respectively. No significant differences were found between the “can’t do, do do” and “can’t do, don’t do” quadrants.

Interpretation

Patients with COPD with a preserved PC seem to have a significantly lower 6-year mortality risk compared with patients with a decreased PC, regardless of physical activity level.

中文翻译：

---

COPD 患者的“能做，能做”象限和 6 年全因死亡率

背景

体能（PC；“可以做”）和体力活动（PA；“做”象限）。这一概念可能有助于更好地了解 PC 和 PA 对 COPD 患者全因死亡率的影响。

研究问题

COPD 患者“可以做，可以做”象限的 6 年全因死亡风险是多少？

研究设计和方法

这项回顾性研究使用了 COPD 患者的数据，这些患者在首次门诊就诊时接受了全面评估。使用 6 分钟步行距离评估 PC，使用加速度计（每天步数）评估身体活动。全因死亡率数据来自市政个人记录数据库。受试者工作特征曲线用于确定 PC 和 PA 的阈值，以预测 6 年全因死亡率。使用派生的阈值，男性和女性患者被分为四个“可以做，做”象限。

结果

来自 829 名患者的数据用于分析。6 年死亡率的最佳判别值是男性 404 m 和 4,125 步/天，女性 394 m 和 4,005 步/天。在 55 个月的中位随访期间（四分位距，37-71 个月），129 名患者（15.6%）死亡。在控制已确定的预后因素后，与“不能做，不做”的患者相比，“可以做，不做”象限和“可以做，做”象限的患者死亡风险显着降低象限：男性的风险比为 0.36（95% CI，0.14-0.93）和 0.24（95% CI，0.09-0.61）和 0.37（95% CI，0.38-0.99）和 0.29（95% CI，0.10-0.87）分别为女性。在“不能做，做做”和“不能做，不做”象限之间没有发现显着差异。

解释

与 PC 减少的患者相比，PC 保留的 COPD 患者的 6 年死亡风险似乎显着降低，无论体力活动水平如何。