Objectives: To determine whether higher circulating levels of thrombotic and inflammatory markers are associated with greater disability.
Design: Cross-sectional.
Setting: Academic medical center.
Participants: A total of 346 men and women with peripheral arterial disease (PAD) and 203 without PAD.
Measurements: Disability measures were the Walking Impairment Questionnaire (WIQ) distance, speed, and stair-climbing scores and the 36-item Short-Form (SF-36) physical functioning score. The SF-36 and WIQ are scored on a 0 to 100 scale (100=best).
Results: In persons with PAD, higher D-dimer levels were associated with lower WIQ speed scores (P<.001), lower stair-climbing scores (P<.04), and poorer SF-36 physical functioning scores (P<.01), adjusting for known and potential confounders. In participants without PAD, higher D-dimer levels were associated with lower WIQ distance scores (P<.03), lower speed scores (P<.05), and poorer SF-36 physical functioning scores (P<.02). Higher high-sensitivity C-reactive protein (hsCRP) levels were associated with lower WIQ distance (P<.02) and speed scores (P<.001) in persons without PAD. Most of these associations were attenuated after additional adjustment for objectively measured functional limitations.
Conclusion: Higher circulating D-dimer and hsCRP levels are associated with greater disability in walking and physical functioning in individuals with and without PAD. Physiological changes that result in walking disability may mediate these associations.