Abstract 17252: The Walking Impairment Questionnaire Predicts Total and Cardiovascular Mortality Independent of Peripheral Artery Disease Status

Abstract

Background: Reduced walking capacity has been associated with increased cardiovascular morbidity and mortality. The Walking Impairment Questionnaire (WIQ) assesses self-reported walking distance, stair climbing and walking speed and has been validated against objective measures of walking ability. Here we test the hypothesis that the WIQ can predict total and cardiovascular mortality in a high risk cardiovascular cohort.

Methods: The WIQ was administered to 1748 patients referred for coronary angiography in the Genetic Determinants of Peripheral Artery Disease (GenePAD) study. Enrollment ABI resulted in 319 diagnoses of PAD. Patients were followed for total and cardiovascular mortality. The association of enrollment WIQ scores with total and cardiovascular mortality was assessed using Cox proportional hazards models adjusted for ankle-brachial index (ABI), age, sex, race, diabetes, smoking and use of lipid-lowering and anti-hypertensive medications.

Results: During a median follow-up period of 5.2 years (interquartile range, 4.0-6.3) 174 mortalities occurred with 48 from cardiovascular causes. Cox proportional-hazards models demonstrated that WIQ scores below the study median were individually associated with total and cardiovascular mortality in all three WIQ categories (Table 1). A significant trend was also noted for greater risk with each additional WIQ category below the study median for total (hazard ratio [HR]=1.50; 95% confidence interval [CI], 1.28-1.74) and cardiovascular mortality (HR=2.01; 95% CI, 1.43-2.82). Test for interaction between the presence of PAD and WIQ category score showed that the observed associations did not significantly differ according to PAD status (p>0.05).

Conclusion: In conclusion, this study is the first to show that lower WIQ walking distance, stair climbing and walking speed scores are associated with increased total and cardiovascular mortality among individuals with and without PAD.