Dajczman Esther, Wardini Rima, Kasymjanova Goulnar, Préfontaine David, Baltzan Marc Alexander, Wolkove Norman
Can Respir J. 2015 Jul-Aug;22(4):225-9. doi: 10.1155/2015/280187.
Chronic obstructive pulmonary disease (COPD) is a progressive and distressing disease with a trajectory that is often difficult to predict.
To determine whether initial 6 min walk distance (6MWD) or change in 6MWD following inpatient pulmonary rehabilitation (PR) predicted survival.
Patients referred for PR in 2010 were studied in a retrospective chart review. Measures of 6MWD before and following PR were recorded. Initial 6MWD was categorized as ≥250 m, 150 m to 249 m and ≤149 m. Government databases provided survival status up until December 2013 and survival analyses were performed. Initial 6MWD and a minimally important difference (MID) of ≥30 m were used for survival analysis.
The cohort consisted of 237 patients (92 men, 145 women) with severe COPD. Mean (± SD) forced expiratory volume in 1 s (FEV1) was 0.75±0.36 L, with a mean FEV1/forced vital capacity (FVC) ratio of 0.57±0.16. Overall three-year survival was 58%. Mean survival for the study period as per predefined categories of 6MWD of ≥250 m, 150 m to 249 m and ≤149 m was 42.2, 37.0 and 27.8 months (P<0.001), respectively, with a three-year survival of 81%, 66% and 34% observed, respectively. Overall mean change in 6MWD was 62±57 m, and a minimal improvement of ≥30 m was observed in 72% of patients. In the lowest walking group, early mortality was significantly higher among those who did not achieve minimal improvement. Older age, male sex and shorter initial 6MWD were negative predictors of survival.
In patients with severe COPD, initial 6MWD was predictive of survival. Overall survival at three years was only 58% and was especially poor (34%) in patients with low (<150 m) initial walk distance.
慢性阻塞性肺疾病（COPD）是一种渐进性且令人痛苦的疾病，其病程往往难以预测。
确定初始6分钟步行距离（6MWD）或住院肺康复（PR）后6MWD的变化是否可预测生存率。
对2010年转诊接受PR的患者进行回顾性病历审查。记录PR前后的6MWD测量值。初始6MWD分为≥250米、150米至249米和≤149米。政府数据库提供截至2013年12月的生存状态，并进行生存分析。初始6MWD和≥30米的最小重要差异（MID）用于生存分析。
该队列包括237例重度COPD患者（92例男性，145例女性）。1秒用力呼气量（FEV1）的平均值（±标准差）为0.75±0.36升，FEV1/用力肺活量（FVC）比值的平均值为0.57±0.16。总体三年生存率为58%。根据预先定义的6MWD类别≥250米、150米至249米和≤149米，研究期间的平均生存时间分别为42.2、37.0和27.8个月（P<0.001），观察到的三年生存率分别为81%、66%和34%。6MWD的总体平均变化为62±57米，72%的患者观察到最小改善≥30米。在步行能力最差的组中，未达到最小改善的患者早期死亡率显著更高。年龄较大性别为男性和初始6MWD较短是生存的负预测因素。
在重度COPD患者中，初始6MWD可预测生存率。三年总体生存率仅为58%，初始步行距离低（<149米）的患者生存率尤其低（34%）。
