Distance-saturation product of the 6-minute walk test predicts mortality of patients with non-cystic fibrosis bronchiectasis

Abstract

Background: Previous surveillance methods to monitor the prognoses of patients with bronchiectasis are too complex for use in daily practice. The 6-minute walk test (6MWT) is a simple exercise test to predict the prognosis of chronic obstructive airway disease and numerous chronic lung diseases, including idiopathic pulmonary fibrosis. No studies have investigated exercise-induced oxygen desaturation (EID) and distancesaturation product (DSP) of 6MWT to predict the prognoses of patients with bronchiectasis. Methods: This was a prospective study to identify correlations between variables of 6MWT and mortality in patients with bronchiectasis over a 6-year period. The study cohort included 69 patients with stable noncystic fibrosis (non-CF) bronchiectasis who were regularly evaluated for functional status via 6-minute walk distance (6MWD), spirometry, BODE index, EID, and DSP.Results: Of the 69 patients, 9 (13%) died and 60 (87%) survived during the 6-year follow-up period. Multivariate analysis showed that DSP (OR =0.983; P=0.001) was the best parameter of 6MWT to predict mortality. Patients with a lower DSP of <280 m% were at a 66.5-fold greater risk (OR =66.5; 95% CI: 9.4-469.2) of 6-year mortality compared with those with DSP >280 m% (P<0.001).Conclusions: DSP is a simple parameter to predict 6-year mortality in patients with non-CF bronchiectasis.

The Effect of Acute Aerobical Exercise on Arterial Blood Oxygen Saturation of Athletes

“…In another study conducted on patients (patients without cystic fibrosis), it was found that oxygen saturation decreasrdafter the 6-min walk test (HSIEH, et al, 2017).…”

Paediatric and adult bronchiectasis: Monitoring, cross‐infection, role of multidisciplinary teams and self‐management plans

“…A small study ( n = 27) found that mean 6‐min walk distance (6MWD) had a stronger correlation with HR‐QoL measures then spirometric indices, whilst a Chinese study described higher mortality in those with a lower 6MWD at baseline . Baseline 6MWD of survivors was 467.9 ± 77.1 m compared to 363.7 ± 126.7 m in those who had died 6 years later . Our literature search revealed no published data on non‐spirometric lung function indices in the paediatric population.…”

“…One study using data from a cohort of 111 adults with bronchiectasis described that pulmonary function indices associated with mortality were higher residual volume (RV)/total lung capacity (TLC) ratio (RR: 1.03, 95% CI: 1.01–1.04), lower TLC (RR: 0.95, 95% CI: 0.93–0.98) and lower transfer coefficient of the lung for carbon monoxide (K CO ) (RR: 0.96, 95% CI: 0.94–0.98) . A small study ( n = 27) found that mean 6‐min walk distance (6MWD) had a stronger correlation with HR‐QoL measures then spirometric indices, whilst a Chinese study described higher mortality in those with a lower 6MWD at baseline . Baseline 6MWD of survivors was 467.9 ± 77.1 m compared to 363.7 ± 126.7 m in those who had died 6 years later .…”

Prognostic ability of the distance‐saturation product in the 6‐minute walk test in patients with chronic obstructive pulmonary disease

“…The product (DSP) of the distance walked in the 6MWT and minimum oxygen saturation (SatO 2 ) obtained during the test includes both variables. As a result, it has been proposed as a predictor of mortality in respiratory diseases like idiopathic pulmonary fibrosis and non‐cystic fibrosis bronchiectasis . However, few studies have evaluated its prognostic ability in patients with COPD at the outpatient level …”

“…As a result, it has been proposed as a predictor of mortality in respiratory diseases like idiopathic pulmonary fibrosis and non-cystic fibrosis bronchiectasis. 12,13 However, few studies have evaluated its prognostic ability in patients with COPD at the outpatient level. 14 The objective of this study was to determine the ability of the DSP (m%) to predict mortality in a cohort of patients with COPD being treated at outpatient pulmonology clinics and to compare it to the BODE index and meters walked in the 6MWT (m6MWT).…”