Ketchell Robert I, Roughton Michael, Agent Penny, Gyi Khin, Hodson Margaret E
Department of Cystic Fibrosis, Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK.
Respir Med. 2009 Oct;103(10):1441-7. doi: 10.1016/j.rmed.2009.04.025. Epub 2009 Jul 16.
The natural history of cystic fibrosis (CF) is unpredictable and the optimal timing for lung transplantation in end-stage disease uncertain. Predicting survival based on FEV1 alone remains controversial and therefore the aim of this study was to assess the value of walk test performance in pre-transplant assessment. Retrospective review of adult patients with end-stage CF who underwent transplant assessment between 1988 and 2004 including a documented walk test on room air, but who died before transplant. The six-minute walk test (6MWT) was used between 1988 and 1993 and the shuttle walk test (SWT) thereafter, the two cohorts were therefore individually assessed. A total of 121 patients were identified. The median (IQR) survival in patients performing SWT (n=77) and 6MWT (n=44) was 363 days (226, 566) and 433 days (232, 844), respectively, with survival in both cohorts significantly associated with pre-test (resting) heart rate (HR) (p<0.03), but not distance walked, pre-test SpO2, FEV1 or BMI. It was predicted that 85% of patients performing SWT with a resting HR of 120 bpm, 70% of those with a HR of 109 bpm (cohort median) but only 25% with a HR of 72 bpm would die within 500 days. Distance walked in the SWT was significantly related to pre-test HR (p<0.01), SpO2 (p<0.01) and Borg score (p=0.016) when performing linear regression. Only pre-test HR remained significant when performing multiple regression. Resting heart rate was the only consistent parameter in this study at predicting a high risk of dying on the transplant waiting list.
囊性纤维化（CF）的自然病史不可预测，终末期疾病进行肺移植的最佳时机也不确定。仅根据第一秒用力呼气量（FEV1）预测生存率仍存在争议，因此本研究的目的是评估步行试验表现在移植前评估中的价值。对1988年至2004年间接受移植评估的成年终末期CF患者进行回顾性研究，这些患者均有在室内空气中进行步行试验的记录，但在移植前死亡。1988年至1993年使用六分钟步行试验（6MWT），此后使用往返步行试验（SWT），因此对这两组分别进行评估。共确定了121例患者。进行SWT（n = 77）和6MWT（n = 44）的患者的中位（四分位间距）生存期分别为363天（226，566）和433天（232，844），两组患者的生存期均与试验前（静息）心率（HR）显著相关（p<0.03），但与步行距离、试验前血氧饱和度（SpO2）、FEV1或体重指数（BMI）无关。据预测，静息心率为120次/分钟的SWT患者中有85%、心率为109次/分钟（队列中位数）的患者中有70%、但心率为72次/分钟的患者中只有25%会在500天内死亡。进行线性回归时，SWT中的步行距离与试验前HR（p<0.01）、SpO2（p<0.01）和博格评分（p = 0.016）显著相关。进行多元回归时，只有试验前HR仍然显著。在本研究中，静息心率是预测移植等待名单上高死亡风险的唯一一致参数。
