Background: Inflammation may be a potential mechanism of aging-related functional decline. We determined whether greater annual increases in levels of high sensitivity C-reactive protein (hsCRP) and D-dimer predicted greater decline in functioning among persons with and without lower extremity peripheral arterial disease (PAD).
Methods: We prospectively studied 296 men and women with PAD and 191 without PAD. Objective measures of functioning, hsCRP, and D-dimer were obtained at baseline and annually for 3 years (mean follow-up = 36.3 +/- 6.4 months).
Results: Among PAD participants, greater annual increases in hsCRP were associated with greater annual declines in 6-minute walk performance (-2.63 ft/mg/L, p =.039) but not in other functional outcomes. Higher prior year absolute hsCRP levels were associated with greater declines in 6-minute walk (-2.93 ft/mg/L, p =.022), summary performance score (-0.038/mg/L, p =.017), and rapid paced 4-meter walk (-0.29 cm/s/mg/L, p =.026) during the subsequent year. Among participants without PAD, greater annual increases in hsCRP were associated with greater annual declines in 6-minute walk (-7.47 ft/mg/L, p =.002), usual-pace 4-meter walk (-0.33 cm/s/mg/L, p <.001), fast paced 4-meter walk (-0.56 cm/s/mg/L, p =.003), and the summary performance score (-0.029 mg/L, p <.001). There were no consistent associations between D-dimer levels and functional decline.
Conclusion: These findings suggest that inflammation may play a role in functional decline in persons with and without PAD.