GAP43 and Stroke: Compared to cross-sectional measurements of healthy controls, absolute GAP-43 concentration in stroke patients was significantly elevated in Days 7–9 (median difference: 1628 pg/mL, 95% CI [333, 3905]; P = 0.007, Fig. 1d) and 3 weeks after stroke (median difference: 1115 pg/mL, 95% CI [106, 2467]; P = 0.02, Fig. 1d), but not in Days 0–1 (median difference: − 207 pg/mL, 95% CI [− 1252, 537]; P = 0.58, Fig. 1d), Days 2–3 (median difference: 270 pg/mL, 95% CI [− 390, 1388]; P = 0.44, Fig. 1d), or 3–5 months (median difference: − 128 pg/mL, 95% CI [− 774, 567]; P = 0.73, Fig. 1d) after stroke.