Aging, hypercoagulability, and leg necrosis in critical limb ischemia.

BACKGROUND

Aging is associated with changes in coagulation status and progression of arterial insufficiency. The purpose of this study was to identify interrelationships among aging, coagulation status, and leg necrosis in patients with critical limb ischemia (CLI).

METHODS

Between March 2010 and February 2013, 103 consecutive patients with CLI were enrolled in this study. Retrospective analyses were performed on patient characteristics including age, gender, the presence or the absence of leg necrosis, diabetes mellitus (DM), hypertension, and smoking, and preoperatively measured baseline coagulability factors, which included measurements of coagulation factors anticardiolipin antibodies IgG and IgM, lupus anticoagulant and factor 8, the fibrinolytic factor tissue plasminogen activator (t-PA), and natural anticoagulants proteins C and S and antithrombin III.

RESULTS

Among 103 patients with CLI, a total of 49 legs from 41 patients presented varying degrees of necrosis. CLI patients with DM and hypertension showed significantly increased incidences of leg necrosis compared with those without (P = 0.000, 0.039, respectively). Patients with CLI and leg necrosis were significantly older compared with the age of those without necrosis (P = 0.007). Blood levels of anticardiolipin antibodies IgG and IgM, factor 8, lupus anticoagulant, and t-PA tended to increase with age. However, blood levels of proteins C and S and antithrombin III decreased with patient age. Patients with CLI and leg necrosis showed significantly increased levels of lupus anticoagulant (P = 0.049) and significantly decreased levels of proteins C and S (P = 0.009 and 0.018, respectively) compared with patients without leg necrosis.

CONCLUSIONS

Patients with CLI and leg necrosis were significantly older compared with those without necrosis; similarly, our results revealed age-related hypercoagulability, with significantly elevated coagulation factor lupus anticoagulant and decreased natural anticoagulants protein C and S levels. From these observations, we conclude that age-related hypercoagulability may be an important mechanism that may facilitate leg necrosis in patients with CLI.