Incidence rates were analyzed via Poisson regression adjusted for eight risk factors, as shown in Table 2, and presented using a restricted cubic spline model. The dashed lines show 95% CIs. The number of patients in the histogram is presented in the second axis. These rates were explored across SPP values in patients with a normal ABI (A) and across ABI values in patients with a normal SPP (B). Lower SPP and ABI levels were associated with a higher risk, even if ABI or SPP was within the normal range.
SPP, skin perfusion pressure; ABI, ankle-brachial index; CI, confidence interval