0
Abstract: Slide Presentations |

CHANGES IN SIX MINUTE WALK TEST MEASUREMENTS OVER TIME AS A PREDICTOR OF MORTALITY IN IDIOPATHIC PULMONARY FIBROSIS FREE TO VIEW

James P. Woodrow, MD*; Chris Lettieri, MD; Dave Greenburg, MD
Author and Funding Information

Walter Reed Army Medical Center, Washington, DC


Chest


Chest. 2008;134(4_MeetingAbstracts):s20001. doi:10.1378/chest.134.4_MeetingAbstracts.s20001
Text Size: A A A
Published online

Abstract

PURPOSE:Idiopathic pulmonary fibrosis (IPF) is a progressive condition with an unpredictable rate of functional decline. While static measures, such as six-minute walk tests (6MWT) and spirometry have been used, they do not reliably measure functional deteriorations or predict outcomes. We sought to determine if the rate of decline would better predict and time mortality than static measures of these variables.

METHODS:Retrospective review of patients with biopsy-proven IPF and two or more evaluations, followed until death, transplant, or end of the observation period. From each encounter we abstracted patient demographics, spirometric values, and 6MWT parameters. 6MWT parameters included distance walked (in meters), oxygen saturation nadir and the distance-saturation product (product of the distance walked and SpO2 nadir). We identified predictors of death using Cox proportional hazard models.

RESULTS:77 subjects were included (77.9% male, mean age 61±11 years). Mean follow-up time was 34 ± 25 months. During the observation the period, there were 30 (39%) survivors and 47 (61%) deaths. Six (7.8%) underwent lung transplantation. All measured variables declined over time. However, the rate of decline was greater among non-survivors and increased as death approached. Of these variables, the distance-saturation product was the most accurate predictor of outcomes. The only independent predictors of death were the final distance-saturation product (HR=0.995; 95%CI= 0.992–0.997) and slope of decline in the distance-saturation product (HR=1.58; 95%CI=1.03–2.40).

CONCLUSION:Functional impairment is common and often progressive in IPF. The rate of decline in the distance-saturation product is a simple tool that independently predicted mortality. Our data suggests that as patients approach death the rate of decline in the distance-saturation product accelerates.

CLINICAL IMPLICATIONS:The rate of decline in 6MWT parameters, especially the distance-saturation product, may add further prognostic value and assistance in the timing of lung transplantation.

DISCLOSURE:James Woodrow, No Financial Disclosure Information; No Product/Research Disclosure Information

Monday, October 27, 2008

2:30 PM - 4:00 PM


Figures

Tables

References

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

CHEST Journal Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543