ICAM1 and major depressive disorder: On the other hand, in the subsample of patients with acute MDD, ICAM-1 showed a strong positive association with a longer duration of the disorder (r = 0.394, p = 0.001, CI: 0.222–0.561) and the duration of the current episode (r = 0.317, p = 0.009, CI: 0.103–0.513).