Figure 5. Lower circulating STAT3 expression in elderly individuals is associated with more major adverse limb events (MALEs). (A) The design of a clinical study focusing on patients with peripheral artery disease (PAD). (B) The expression of circulating STAT3 in young (<65 y/o) and old (≥65 y/o) patients. (C) The expression of circulating STAT3 in patients with or without MALEs. (D) A Kaplan–Meier plot of MALEs among young patients with high STAT3, young patients with low STAT3, old patients with high STAT3, and old patients with high STAT3 (N = 11–20, *P < 0.05), *The cutoff value of STAT3 is defined as 15 ng/ml.