In:
Respiration, S. Karger AG, Vol. 75, No. 4 ( 2008), p. 418-426
Abstract:
〈 i 〉 Background: 〈 /i 〉 The 6-min walk distance (6-MWD) is a global marker of functional capacity and prognosis in chronic obstructive pulmonary disease (COPD), but less explored in other chronic respiratory diseases. 〈 i 〉 Objective: 〈 /i 〉 To study the role of 6-MWD in chronic hypercapnic respiratory failure (CHRF). 〈 i 〉 Methods: 〈 /i 〉 In 424 stable patients with CHRF and non-invasive ventilation (NIV) comprising COPD (n = 197), restrictive diseases (RD; n = 112) and obesity-hypoventilation-syndrome (OHS; n = 115), the prognostic value of 6-MWD for long-term survival was assessed in relation to that of body mass index (BMI), lung function, respiratory muscle function and laboratory parameters. 〈 i 〉 Results: 〈 /i 〉 6-MWD was reduced in patients with COPD (median 280 m; quartiles 204/350 m) and RD (290 m; 204/362 m) compared to OHS (360 m; 275/440 m; p 〈 0.001 each). Overall mortality during 24.9 (13.1/40.5) months was 22.9%. In the 424 patients with CHRF, 6-MWD independently predicted mortality in addition to BMI, leukocytes and forced expiratory volume in 1 s (p 〈 0.05 each). In COPD, 6-MWD was strongly associated with mortality using the median [p 〈 0.001, hazard ratio (HR) = 3.75, 95% confidence interval (CI): 2.24–6.38] or quartiles as cutoff levels. In contrast, 6-MWD was only significantly associated with impaired survival in RD patients when it was reduced to 204 m or less (1st quartile; p = 0.003, HR = 3.31, 95% CI: 1.73–14.10), while in OHS 6-MWD had not any prognostic value. 〈 i 〉 Conclusions: 〈 /i 〉 In patients with CHRF and NIV, 6-MWD was predictive for long-term survival particularly in COPD. In RD only severely reduced 6-MWD predicted mortality, while in OHS 6-MWD was relatively high and had no prognostic value. These results support a disease-specific use of 6-MWD in the routine assessment of patients with CHRF.
Type of Medium:
Online Resource
ISSN:
0025-7931
,
1423-0356
Language:
English
Publisher:
S. Karger AG
Publication Date:
2008
detail.hit.zdb_id:
1464419-8
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